Food Date Labels Explained

How to Determine the Shelf Life of Food Guidance Document – Source MPI

This guidance document has been developed to help operators to determine the shelf life of their food
products and to apply the appropriate date marking. It provides useful information to assist operators
preparing and handling foods for retail sale. Any legal requirements are shown in boxes with quotation marks.
They are either directly quoted from the requirements (including any clause numbers) or are summarised
when the requirement is too long to include completely. It is the operator’s responsibility to be aware of and
comply with all applicable current legislation including any requirements that amend, replace or correspond to
the requirements referenced in this guidance document.
This guidance document was amended in June 2016 to:
correct a legal error in section 8 of the guidance document;
include a copy of the date mark alteration application form; and
update the references to the Food Standards Code.
Related Requirements
Food Standards Australia New Zealand, Food Standards Code Standard 1.2.5 – Information requirements –
date marking of food for sale https://www.comlaw.gov.au/Series/F2015L00401
Food Standards Australia New Zealand Food Standards Code Standard 1.2.6 – Information requirements –
directions for use and storage https://www.legislation.gov.au/Series/F2015L00393
Food Standards Australia New Zealand, Food Standards Code Standard 1.6.1 – Microbiological limits in food
https://www.comlaw.gov.au/Series/F2015L00411
Food Standards Australia New Zealand Food Standards Code Schedule 27 Microbiological limits in food
https://www.comlaw.gov.au/Series/F2015L00453
Food Act 2014: http://www.legislation.govt.nz/act/public/2014/0032/latest/DLM2995811.html?src=qs
Document history

Contact Details
This publication is available from the Ministry for Primary Industries:
Telephone: 0800 00 83 33
PO Box 2526
WELLINGTON 6140
Email: [email protected]
Telephone: 0800 00 83 33
This publication is also available on the Ministry for Primary Industries website at
http://www.foodsafety.govt.nz/industry/general/labelling-composition/
Disclaimer
This guidance document does not constitute, and should not be regarded as, legal advice. While every effort has been made to ensure the information in this guidance document is accurate, the Ministry for Primary Industries does not accept any responsibility or liability whatsoever for any error of fact, omission, interpretation or opinion that may be present, however it may have occurred.
Copyright
Crown copyright ©. This copyright work is licensed under the Creative Commons Attribution 3.0 New Zealand
licence. In essence, you are free to copy, distribute and adapt the work, as long as you attribute the work to the Ministry for Primary
Industries and abide by the other licence terms. To view a copy of this licence, visit http://creativecommons.org/licenses/by/3.0/nz/.
Please note that no governmental emblem, logo or Coat of Arms may be used in any way which infringes any provision of the Flags,
Emblems, and Names Protection Act 1981 or would infringe such provision if the relevant use occurred within New Zealand.
Attribution to the Ministry for Primary Industries should be in written form and not by reproduction of any such emblem, logo or Coat of
Arms.
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food

Contents
1 Scope
2 Definitions
3 Shelf life
4 Changes that may occur during processing and storage
4.1 Deterioration and spoilage
4.2 Factors that affect the rate at which food deteriorates and spoils
4.3 Hazard Analysis and Critical Control Point (HACCP) systems
4.4 Effect of processing on survival of microorganisms
4.5 Effects of chilled storage
4.6 Loss of nutrients during storage
5 Shelf life and date marking requirements
6 When a ‘use-by’ date is required for safety reasons
6.1 There may be a food safety concern
6.2 Using the FSANZ decision tree to determine when a ‘use-by’ date is needed
7 How to determine the shelf life of a ready-to-eat food
7.1 Methods
7.2 Shelf life studies (direct method) for a ‘best-before’ date
7.3 Indirect methods for ‘best-before’ date marking
7.4 When there is significant nutrient loss and a ‘use-by’ date is required
7.5 When there is potential for growth of a pathogen and a ‘use-by’ date is required
7.6 Shelf life of composite foods
8 Date marking changes
8.1 When a date mark may need to be changed
8.2 The regulatory requirements
8.3 Applying for permission to change a date mark
8.4 Examples where permission is not required from MPI to change a date mark
9 Factors that influence shelf life
9.1 Intrinsic and extrinsic factors
10 Pathogenic bacteria associated with ready-to-eat chilled foods
10.1 Listeria monocytogenes
10.2 Clostridium botulinum
10.3 Bacillus cereus
10.4 Yersinia entercolitica
11 Useful links
11.1 Shelf life and date marking in general
11.2 Foodborne disease surveillance
11.3 Listeria monocytogenes
11.4 Clostridium botulinum
11.5 Predictive modelling
11.6 Challenge modelling
12 Date Mark Alteration Application Form

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Guidance Document: How to Determine the Shelf Life of Food
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1 Scope
This guidance document is intended to help food operators who process, prepare and handle food to
determine the shelf life of their food products and to apply appropriate date marking. It describes:
 how shelf life is defined;
 the causes of food deterioration and spoilage;
 why food may become unsafe during storage;
 how to decide whether a ‘best-before’ or ‘use-by’ date mark is required;
 the information needed to work out what the shelf life is; and
 how to ensure the safety of chilled foods.
The shelf life of many foods can be extended through various means including chilled storage. Low
temperatures slow down chemical changes and growth of many spoilage and pathogenic microorganisms
(bacteria, yeasts and moulds) and any toxin formation. However some pathogenic bacteria are able to grow at
the low temperatures used for refrigeration and chilled storage. These are referred to as cold-tolerant bacteria.
The type and length of storage may provide the suitable conditions and time for the cold-tolerant bacteria to
grow in number so that the food becomes unsafe after a period of time, even if low numbers are present after
manufacture. This will impact on the shelf life and safety of the food especially where the food is considered to
be ready-to-eat. Ready-to-eat foods are those foods where there is no further processing that will reduce or
eliminate harmful microorganisms before consumption.
The focus of this guidance document is therefore on determining the shelf life of chilled ready-to-eat foods.
This guidance document may provide some useful information for manufacturers and processors of other
foods.
In this guidance document for any references to sections included refer to sections in this guidance document
unless it is otherwise stated.
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Guidance Document: How to Determine the Shelf Life of Food
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2 Definitions
‘Best-before’ means the date until when, provided the food has been stored in intact packaging and in
accordance with stated storage conditions, it will be fully marketable and retain its quality.
Chilled foods are those foods that require storage at 5˚C or less to maintain their suitability and safety.
Date marking is the system for packaged foods with a shelf life of less than two years.
FSANZ means Food Standards Australia New Zealand. FSANZ is a bi-national Government agency
responsible for developing and administering the Australia New Zealand Food Standards Code (the Code),
which lists requirements for foods such as additives, food safety, labelling and GM foods.
Microorganisms include moulds, yeasts and bacteria. Bacteria includes pathogens and spoilage organisms,
spore-forming bacteria and those that may cause food poisoning through the production of toxins.
Perishable food is unprocessed or processed food that has a short shelf life at room temperature before
showing signs of deterioration or spoilage (often mould or bacterial growth seen as fur or slime), e.g. fruit or
pre-packaged bread.
Shelf life is the period of time, established under intended conditions of distribution, storage, retail and use,
that the food would remain safe and suitable.
Shelf life testing requires foods to be stored under the expected conditions of storage and distribution for a
period of time to determine at what point chemical changes, deterioration and/or spoilage of the food occurs.
Shelf-stable food is food of a type that, because of its composition (low moisture, high salt or sugar content)
does not require to be refrigerated for storage or a food which would normally be stored refrigerated but which
has been processed so that it can be safely stored in a sealed container at room temperature for a usefully
long shelf life.
‘Use-by’ date is the date until when, provided the food has been stored in intact packaging and in accordance
with stated storage conditions, it is safe to eat.
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Guidance Document: How to Determine the Shelf Life of Food
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3 Shelf life
The stated shelf life of a food is the period of time for which it remains safe and suitable for consumption,
provided the food has been stored in accordance with any stated storage conditions. This means that the
food:
 must remain safe to consume, i.e. should not cause food-poisoning because of the growth of
pathogenic bacteria or the production of toxins (bacterial and fungal) in the food during storage;
 has not deteriorated in quality or spoiled in any way that the consumer would find unacceptable;
and
 has not lost significant amounts of any nutrients listed on the label.
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Guidance Document: How to Determine the Shelf Life of Food
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4 Changes that may occur during processing and storage
4.1 Deterioration and spoilage
Food is perishable by nature. Changes will take place naturally in all food while it is being handled and stored
by the processor, retailer and the consumer. The changes can be rapid as with spoilage of raw meat and fish
or spoilage and deterioration can take place over a period of days or weeks, e.g. bread becomes mouldy,
biscuits become stale and soft, and processed meats become smelly and slimy. For some foods, e.g. retorted
and very dry foods, the deterioration in the quality may not become apparent until after months or even years
of storage. These foods are described as shelf-stable.
4.2 Factors that affect the rate at which food deteriorates and spoils
There are many factors that may affect the shelf life of a product. Some factors relate to the food itself
(intrinsic factors), such as moisture and pH, while others are external to the product (extrinsic factors), e g. the
packaging conditions, materials and storage conditions. By understanding which are the most important
factors impacting on the shelf life of a food, it may be possible to manipulate these factors to extend the shelf
life. Information on the factors that influence and cause food deterioration and spoilage and thus the shelf life
of a food can be found in section 9.
Altering the composition, formulation, processing or packaging may inadvertently lead to a decrease in the
shelf life or make the food more susceptible to the growth of spoilage or even pathogenic microorganisms. So
it is important to assess any changes proposed for their potential to have an adverse effect on shelf life. This
will be especially important if the safety of a food relies on a number of interacting factors or hurdles to inhibit
the growth of pathogenic bacteria.
4.3 Hazard Analysis and Critical Control Point (HACCP) systems
It is essential to understand how the ingredients, process, final characteristics, packaging and storage
conditions influence the safety, as well as deterioration and spoilage of a food. This will require an
understanding of:


what biological hazards are reasonably likely to be present; and
the effectiveness of the control measures in place throughout the process at killing or inhibiting the
growth of pathogenic bacteria in the food.
A review of the entire production process using hazard analysis will assist in identifying the potential for the
hazards of concern to be present. In particular the four key cold-tolerant bacteria, which need to be controlled
during the shelf life (refer to section 10) and the relevant control measures. See Table 1 for information on the
effect of processing on microorganisms.
Control may be applied at critical control points (CCPs) which are steps at which a process is applied to
prevent, eliminate or reduce a food safety hazard to an acceptable level, e.g. application of heat. Alternatively
it may come from the application of hurdle technology. Hurdle technology refers to the concept of achieving
control by combining in series, a number of measures that would not individually be adequate for control. For
example uncooked fermented meats such as salami where the hurdles are the rapid development of a low pH
along with the reduction in the water content by drying and the addition of inhibitory salts.
Further information on using HACCP is on the MPI website:
http://www.foodsafety.govt.nz/industry/general/haccp/using-haccp.htm
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4.4 Effect of processing on survival of microorganisms
The processing of a food may eliminate or at least reduce the number of microorganisms present. This will
help to make food safe by controlling pathogenic bacteria (those able to cause illness) and may extend the
shelf life of the food by reducing the numbers of spoilage microorganisms (that cause food to go off). Table 1
in section 9 provides a summary of the effect of processes applied to food on the elimination and survival of
microorganisms that could be present in a food.
Many processes applied to food, e.g. washing fresh produce or pasteurising, will not eliminate all the
microorganisms present and a few may survive processing. Processed foods other than those that are
retorted or receive an ultra-high temperature (UHT) treatment are not sterile. If the conditions during storage
permit bacteria to grow, the food could become unsafe to consume. This may occur even if the bacteria in the
food have been reduced to a safe level (even below the limit of detection of the laboratory method) following a
validated process. Some pathogenic and spoilage bacteria produce spores that can be very resistant to heat
and may not be eliminated during processing. If these spore-forming and/or cold-tolerant bacteria could be
present after processing, this will need to be taken into account when establishing the shelf life. Spores from
fungi (mould) on the other hand are easily destroyed by heat processing.
Processing using an appropriate validated heat treatment will decrease the numbers of pathogenic bacteria
present in the raw materials and ingredients. Some food preservation techniques such as fermenting or cold-
smoking, if not adequately controlled, have the potential to increase the number of pathogenic bacteria
present and may result in a reduced shelf life.
Where there is an expectation that processing will reduce the number of microorganisms present, make the
food safer and extend the shelf life. This can be compromised if re-contamination occurs, for example, cross-
contamination during processing.
4.5 Effects of chilled storage
The shelf life of many foods can be extended through chilled storage. Low temperatures slow down chemical
changes and the growth of many moulds, yeasts and spoilage and pathogenic bacteria. However there are
some microorganisms including pathogenic bacteria that are able to grow readily at low temperatures. In
some situations, while the levels of these cold-tolerant pathogenic bacteria may be considered safe at the end
of processing if the duration of the shelf life is extended it provides a greater opportunity for these pathogenic
bacteria to grow. This will have a major impact on the shelf life of the food. Section 10 provides information on
the four key pathogenic bacteria that are a concern for chilled foods.
4.6 Loss of nutrients during storage
Nutrient levels may decrease in a food over time. The rate of loss will depend on the stability of the particular
nutrient. If the nutrient levels could decrease to below the expected level (i.e. as stated on the label), a ‘use-
by’ date is needed to indicate the point in time at which the nutrient levels will be less than the level stated on
the label (see section 6). This includes foods where the nutritional profile and the maintenance of these levels
in the food are critical to the health of the intended consumer. This is important for foods which are a major
nutritional source for a specific group of consumers.
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Guidance Document: How to Determine the Shelf Life of Food
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5 Shelf life and date marking requirements
Food sold in Australia and New Zealand must meet the requirements of the Australia New Zealand Food
Standards Code (the Code) and the New Zealand Food Act 2014. Standard 1.2.5 in the Code details the date
marking required for packaged food. A copy of the Code can be found at:
http://www.foodstandards.gov.au/code/Pages/default.aspx
Standard 1.2.5 requires that:
“1.2.5—3
Food for sale must be date marked on labels
(1)
For the labelling provisions, the date marking information is:
(a)
if there is a *use-by date for the food—that date; or
(b)
otherwise—any of:
(i)
the *best-before date of the food; or
(ii)
for bread that has a shelf life of less than 7 days:
(A)
the best-before date; or
(B)
(C)
(2)
the *baked-for date; or
the *baked-on date.
The date marking information is not required if:
(a)
the *best-before date of the food is 2 years or more after the date it is
determined; or
(b)
the food is an individual portion of ice cream or ice confection.
(3) Despite subsection (1), if the food is in a small package, the only date-marking
information required is the *use-by date (if any).
Note The labelling provisions are set out in Standard 1.2.1.”
Date marking can be either a ‘use-by’ or a ‘best-before’ date and begins from the time when the food is
prepared or manufactured. Additional date marking options are provided for bread with a shelf life less than
seven days.
The definitions in Standard 1.2.5 are:
“Best-before date, for a food for sale, means the date up to which the food for sale will remain fully
marketable and will retain any specific qualities for which express or implied claims have been made, if the
food for sale:
a)
b)
remains in an intact package during its storage; and
is stored in accordance with any storage conditions applicable under Standard 1.2.6.
Use-by date, for a food for sale, means the date after which it is estimated that the food for sale should
not be consumed because of health or safety reasons, if the food for sale:
a)
b)
remains in an intact package during its storage; and
is stored in accordance with any storage conditions applicable under Standard 1.2.6.”
‘Use-by’ dates may be applied where the date marking is required for:
 health reasons, e.g. to comply with the label declaration of a nutrient; or
 for safety reasons, e.g. to remain safe (due to the presence and/or growth of pathogenic
microorganisms and any toxic substances produced).
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Guidance Document: How to Determine the Shelf Life of Food
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Standard 1.2.5 also prescribes the form of date mark and the form of date. The Code also requires that the
label on a package of food must include a statement of any specific storage conditions required to ensure that
the food will keep for the period indicated by the ‘use-by’ or the ‘best-before’ date (subsection 1.2.6—2(a)).
For further information refer to the FSANZ Date Marking User Guide to Standard 1.2.5 – Date Marking of
Food outlines the requirements. The FSANZ User Guide can be used to decide whether a ‘best-before’ or
‘use-by’ date is appropriate for a food.
http://www.foodstandards.gov.au/code/userguide/Pages/datemarking.aspx
This FSANZ user guide provides information to assist food processors to understand how to ensure that the
shelf life and date marking assigned to a product have a scientific basis. You should be able to explain how a
date mark has been arrived at and have records to support this in the event that concerns are raised about
the appropriateness or safety of the date marking applied.
Standard 1.2.6 of the Code requires that the label on a package of food must include directions for the use of
the food or the storage of the food, or both, if the food is of such a nature as to require the directions for health
or safety reasons. This provision may include the need to provide storage instructions of a food product (for
both intact and opened packaging) to maintain the determined ‘use-by’ date. Standard 1.2.6 is available at:
https://www.comlaw.gov.au/Series/F2015L00393
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Guidance Document: How to Determine the Shelf Life of Food
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6 When a ‘use-by’ date is required for safety reasons
6.1 There may be a food safety concern
A ‘use by’ date is required for safety reasons where a food could become unsafe during its shelf life. The
formation of toxic substances or the growth of pathogenic microorganisms may not provide visible signs that
the product could have become unsafe to eat.
It is relatively uncommon for constituents of the food to breakdown or change so that toxic substances are
formed, e.g. oxidation of fats and oils. The potential for this to occur will usually be mitigated by:
the addition of substances that reduce the potential for the changes to occur, e.g. antioxidants;
packaging to reduce exposure to light which may cause changes; and
storage instructions, e.g. refrigerate or store in a dark space.
However if the potential remains for toxicity to develop, a ‘use-by’ date is required for a safety reason.
Modern technological improvements to food processing, ingredients, packaging and storage has decreased
the potential for chemical toxicity developing in the food. A greater diversity of foods with a prolonged chilled
storage has increased the potential for pathogenic bacteria to be present. This will mean that the use and
validation of ‘use-by’ date marking has become very important.
Before the start of refrigerated storage and modern food technology, foods were preserved using processes
such as drying, salting, pickling and fermentation, either on their own or in combination. These foods could be
stored at room temperature for long periods. As well as the food being preserved, pathogenic microorganisms
would usually be inhibited from growing and they would die off over time. Today milder forms of processing
are preferred, so that foods are not as dry, salty or acidic. This often produces a product that is more
acceptable to consumers, but these products will have a shorter shelf life than the traditional product. Chilled
storage and special packaging can be used to restrict the growth of pathogens and spoilage bacteria during
storage, e.g. gas flushing, vacuum packing, etc. but this does not always result in an extended shelf life. This
is because the storage conditions may actually favour the growth of some microorganisms’, e.g. cold-tolerant
spoilage and pathogenic microorganisms and those that thrive in the absence of oxygen.
Home produced foods, e.g. dips and sauces, are normally consumed within hours of being made. However
when these are produced commercially, they will need an extended shelf life, usually several weeks in length.
Extending the shelf life may be achieved by a combination of factors relating to the formulation of the food,
type of processing applied and the use of refrigerated storage. However these may not be sufficient to prevent
the survival and growth of any pathogenic bacteria present and so it may be necessary to:
 reformulate or package the food so that growth cannot occur;
 ensure that there are no pathogenic bacteria present, e.g. treat the product in its final packaging;
 reduce the shelf life so there is less time for pathogens to grow to unsafe levels;
 reduce the potential for pathogens to survive by increasing the severity of processing, e.g. replace
pasteurisation with UHT; or
 adopt more rigorous ingredient specifications.
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Guidance Document: How to Determine the Shelf Life of Food
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6.2 Using the FSANZ decision tree to determine when a ‘use-by’ date
is needed
Once it has been determined that a ‘use-by’ date for health reasons is not required, this decision tree from the
FSANZ Date Marking User Guide can be used:
http://www.foodstandards.gov.au/code/userguide/Pages/datemarking.aspx.
To assist with the interpretation of the decision tree, each of the steps has been numbered and explanatory
text provided.
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Guidance Document: How to Determine the Shelf Life of Food
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Figure 1: Decision tree: Applying a ‘use-by’ date for safety issues
Source ‘FSANZ Date Marking, User Guide to Standard 1.2.5 – Date Marking of Food’
Yes
Step 1: Is the food a shelf-stable food?
No
Yes
Step 2: Is the food a frozen food?
No
Step 3: Is the food a raw food that requires a process such as cooking to
reduce or eliminate food poisoning bacteria to make the food safe to eat?
No
Step 4: Is the food a chilled ready to eat food?
Yes
Step 5: Is there a reasonable likelihood that the food could contain any of
the following food poisoning bacteria:
•Listeria monocytogenes;
•Psychrotrophic strains of Bacillus cereus;
•Psychrotrophic strains of Clostridium botulinum; or
•Yersinia enterocolitica?
Yes
Step 6: Will the food discernibly spoil before the levels of bacteria would
reach dangerous levels?
No
‘Use-by’ date may
be appropriate
‘Best-before’ date may be
appropriate, if shelf life is less than
two years
Yes
No
Yes
No
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Explanatory text
Step 1
Shelf-stable foods are those that do not require any special storage conditions as they generally do not
provide conditions suitable for the growth of microorganisms, e.g. very dry, high acid, high sugar or salt
content. Foods preserved in these ways will eventually show deterioration in flavour and appearance but this
may take a long time.
Foods that have been subjected to a process capable of killing both vegetative bacteria as well as spores will
also result in shelf-stable food provided the food cannot become recontaminated after processing, e.g.
canning and retorting in the final package. This often results in a shelf life of greater than two years and this
situation date marking is not required.
Note that the exemption from date marking requirements for foods with a shelf life greater than 2
years i.e. shelf-stable does not apply to infant formula. Infant formula must have a date mark see
subsection 2.9.1—22(2) of the Code.
Step 2
No pathogenic foodborne microorganisms and very few food spoilage microorganisms other than some
moulds can grow in frozen food.
However, if it is intended that the food is to be thawed before consumption, proceed to step 3. If there is an
extended time between the thawing of a food and it being consumed without further cooking, any
microorganisms present may then be able to grow to harmful levels.
Step 3
Foods that are intended to be cooked thoroughly by the consumer before eating must be clearly labelled with
cooking instructions. These foods are not ready-to-eat and appropriate preparation and storage should reduce
any pathogenic microorganisms present to safe levels. A ‘best-before’ date may be appropriate.
Step 4
Some pathogenic cold-tolerant bacteria are able to grow in refrigerated foods, i.e. foods stored below 5˚C.
Low numbers of these bacteria may grow during chilled storage and could reach unsafe levels or enable the
production of toxins. These bacteria may either survive processing or can be introduced onto the food after
processing, e.g. during preparation of consumer packs.
Step 5
Could any of the four cold-tolerant bacteria listed in the flow chart be present at the start of the product’s shelf
life?
Spores of Clostridium botulinum and Bacillus cereus may remain in the product if the process is designed to
deal with vegetative pathogens only. The product will be safe to consume as long as the spores are not able
to germinate and grow to unsafe levels during storage.
L. monocytogenes and Y. enterocolitica are potential contaminants of foods that are minimally processed or
do not receive a processing treatment that will be able to eliminate the microbiological hazard of concern.
Some foods may become contaminated from the processing environment following a valid processing
treatment before final packaging.
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The shelf life is based on the ability of these pathogens, if present, to survive and grow under the intended
storage conditions.
For more in depth information on each of the pathogenic bacteria and the impact of food processing on their
survival refer to sections 9 and 10 and to the Pathogen Data Sheets on MPI’s website
http://www.foodsafety.govt.nz/science-risk/hazard-data-sheets/
Important note
 For chilled ready-to-eat food produced in New Zealand using locally produced ingredients,
Listeria monocytogenes is the key hazard of concern, as it has been associated with foodborne
illness and is frequently isolated from food and the processing environment
 For Clostridium botulinum there are differing situations:
– Surveys and other scientific studies suggest that cold-tolerant Clostridium botulinum is
unlikely to be a hazard reasonably likely to occur in ingredients or unprocessed food of New
Zealand origin. Therefore specific controls to manage this hazard may not be necessary.
– For imported ingredients or foods cold-tolerant C. botulinum may be a hazard reasonably
likely to occur. It will be important to determine what controls are in place and how these can
be maintained.
– If you are producing food or ingredients for export using New Zealand-only ingredients,
although cold-tolerant C. botulinum is not a hazard likely to occur, overseas markets may
require evidence that the process is capable of inactivating these hazards.
 Cold-tolerant B. cereus is a spore-forming bacteria that is a hazard reasonably likely to occur in
foods and ingredients.
 While Yersinia entercolitica does occur in New Zealand, it is unclear to what extent it is
transmitted through food. Overseas Yersinia has been linked foods such as processed meat
products. MPI believes that processes capable of managing Salmonella and L. monocytogenes
will be equally capable of dealing with any Y. enterocolitica that may be present.
 Operators should review available evidence including surveys of incidence and cases of illness
associated with these four cold-tolerant bacteria in New Zealand.
http://www.foodsafety.govt.nz/science-risk/human-health-surveillance/
You can identify whether growth of microorganism in the food will occur by:
 Identifying the intrinsic compositional characteristics of the food (e.g. pH, salt content and water
activity, etc.) that would prevent growth occurring. Refer to sections 9 and 10, and the hazard data
sheets at http://www.foodsafety.govt.nz/science-risk/hazard-data-sheets/ for more information on
what conditions the pathogenic bacteria need for growth.
 Using predictive microbiological models (computer based models) to predict the growth of some
microorganisms (spoilage and pathogenic bacteria) in foods with specific characteristics (e.g. pH,
salt content and water activity, etc.) The models may be limited in their applicability due to the
range of parameters that they are able to cover, and they may over estimate growth if the model
was developed using growth studies in laboratory media. Section 10 lists the most commonly used
models and where information on how to use them can be found.
 Undertaking challenge tests, i.e. inoculate the food with a known concentration of appropriate
strains of the pathogenic bacteria and see if they can grow and at what rate. Protocols for
challenge studies are shown in section 11. While challenge tests are the best method for
determining whether or not growth will occur, they are expensive to do. However the cost would be
offset by the assurances testing provides.
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Before undertaking any investigation to determine the shelf life or the growth of pathogenic bacteria, it is
important to ensure that the processing consistently produces a safe food with the same characteristics, e.g.
acidity, moisture content, etc. (refer to section 9). This can be achieved by implementing a HACCP
programme and undertaking process validation studies. For further information on validation refer to the Risk
Management Programme Manual, available on the MPI website at: www.mpi.govt.nz
Shelf life testing is where foods are stored under the expected conditions of storage and distribution for a
period of time. This helps to determine at what point chemical changes, deterioration and/or spoilage of the
food occurs and helps to determine the shelf life with respect to these characteristics rather than with respect
to the growth of a pathogenic microorganism or toxin production.
Further information on direct and indirect methods of shelf life testing is provided in section 7.
If challenge testing or predictive microbiological modelling predicts that growth of L. monocytogenes will
occur, consider risk management strategies that would reduce or limit growth such as:
 using frozen rather than chilled storage and distribution, e.g. for ready-to-eat cold smoked fish,
especially if it is to be transported over long distance;
 increasing the use of microbiological hurdles and other factors that would minimise growth such as
reducing moisture or increasing salt or acidity;
 the addition of preservatives specific for the pathogen of concern; or
 an in-pack pasteurisation step. This will reduce the numbers of both spoilage microorganisms and
vegetative pathogenic bacteria present.
Step 6
If it is possible that cold-tolerant pathogenic bacteria could be present in the food and could grow during
storage, a ‘use-by’ date could be necessary. However, this would only be the case if the level of these
pathogenic bacteria could make the food unsafe before the growth of spoilage microorganisms has made the
food unacceptable. In Figure 2, there are three scenarios to demonstrate the growth of spoilage
microorganisms and pathogenic bacteria in a chilled food shown.
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Figure 2: How the growth of microorganisms impacts on shelf life and date marking
Scenario A: Food supports the growth of both pathogenic and spoilage bacteria during storage and
the pathogenic bacteria reach unsafe levels before the food is visibly spoiled
Outcome: A ‘use-by’ date is required to ensure the food is not consumed when pathogen levels could be
unsafe.
Key
— Critical level of spoilage
microorganisms
———-— Unsafe level of pathogens
ques Spoilage microorganisms
—— Pathogens
Storage tie
Scenario B: Food supports the growth of both pathogenic and spoilage bacteria during storage but
the food is visibly spoiled before pathogenic bacteria have reached unsafe levels
Outcome: A ‘best-before date’ may be appropriate
Key
— Critical level of spoilage
microorganisms
——-—— Unsafe level of pathogens
memes Spoilage microorganisms
==Pathogens
Storage tie
>
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Number of microorganisms
Number of microorganisms
v
Vv

Guidance Document: How to Determine the Shelf Life of Food
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Scenario C: The pathogenic bacteria may sometimes be present at very low (safe) levels but do not
grow in the food. Spoilage bacteria can grow and the food becomes visibly spoiled
Outcome: A ‘best-before’ date is appropriate
<—_——— Sheff life—______ ft
Key
seteeesenenseses Critical level of spoilage
microorganisms
———— Unsafe level of pathogens
wees Spoilage microorganisms
Pathogens
Storage time
ee
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7 How to determine the shelf life of a ready-to-eat food
7.1 Methods
Both direct and indirect methods are possible. Direct methods may take longer but will be the more accurate,
e.g. a storage trial using realistic and defined storage conditions such as shelf life or challenge trials. Indirect
methods are quicker but less accurate, which may mean adjustment is needed once product is in the market.
Indirect methods include accelerated shelf life tests where the food is stored at a higher than expected
temperature or through the use of historical data collected or computer based models, e.g. predictive
microbiological models.
Before undertaking any investigation to determine the shelf life or the growth of pathogenic bacteria in a food,
it is important to ensure that the processing consistently produces a safe food with the same characteristics,
e.g. acidity, moisture content, etc. (refer to section 9). This can be achieved by implementing a HACCP
programme and undertaking process validation studies. For further information on validation refer to the Risk
Management Programme Manual.
7.2 Shelf life studies (direct method) for a ‘best-before’ date
This requires the food to be stored for a period of time that is longer than the expected shelf life, in order to
observe, test and record changes in the products characteristics. From this information a shelf life can be
estimated. The shelf life will need to take into account possible variability between product batches and
storage conditions, including whether the product is intended to be consumed over a period of time. Where
this is the case the food should be subject to a number of repeated temperature fluctuations, such as cycling
from refrigeration to room temperatures. For some products it will be important to take into account conditions
that could impact unfavourably during normal storage and transport. For example, some emulsions may be
adversely affected by being shaken during distribution.
The shelf life determination should be made with product processed under normal commercial conditions, it is
recommended that during the development of new products, shelf life studies are included. This will allow
changes to the formulation, processing or packaging to be made during the development stage if the shelf life
appears to be less than what is expected or there are unacceptable variations between batches.
Step 1: Setting up the study
 Identify the type(s) of spoilage or loss of quality most commonly associated with the food. These
will be: yeast, mould and/or bacterial spoilage, changes in texture, smell, taste or appearance.
Decide which of these are most important and which changes will occur first. One type of
deterioration may dominate or several may be equally important.
 Identify whether there is likely to be any growth of pathogens during the shelf life. If there is,
challenge testing may also be appropriate (refer to section 6).
If the testing is to include tasting the food, it is important that there is confidence that the food could not be
a potential source of food poisoning. If there is any doubt in this respect, do not do taste tests.
 Identify the observations and tests that will be undertaken. These may be made by:
– subjective sensory testing, e.g. colour and textural changes, smell and taste; or
– objective laboratory tests, e.g. numbers of spoilage bacteria or yeasts appearance of mould
growth, presence of a chemical indicator of deterioration, such as D-alanine in fruit juice,
rancidity, histamine in seafood, etc.
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 Use published literature, observation of similar products in the market and past experience to
identify the expected shelf life, so that you know whether the testing is likely to take days, weeks or
months.
 Decide on the storage conditions for the trial. These must reflect the normal expected conditions of
distribution and storage for the product and must be controlled to be the same every trial.
 Consider including additional storage conditions in the trial if these could have an impact on the
shelf life in an intended market or due to the actions of the purchaser of the product. Conditions can
be defined as:
– optimum, i.e. storage as on the label for the whole shelf life;
– realistic, e.g. repeated short periods of elevated temperatures or different levels of humidity;
– worst case, e.g. to mimic product moving from a temperate to a tropical market, poor
temperature control in a domestic refrigerator, the effect of light on a sensitive product, effect of
movement and vibration.
In each situation, at least temperature and humidity may need to be taken into account. Incubators and
cabinets may be used to provide a constant environment for storing the trial samples. Refrigerators set at
different temperatures (e.g. less than 4˚C or more than 10˚C) can provide insight into the impact of
temperature on shelf life. Ideally a range of six temperatures (and not less than three) should be used that
reflect the range and extremes that the product could be exposed to.
For products with a long shelf life, ‘accelerated’ studies may be performed in which the product is exposed to
elevated temperatures to hasten the development of spoilage and deterioration and shorten the time that the
study takes. This would only be useful if the spoilage patterns remain the same as for the normal storage
conditions. Get advice from an expert before doing this type of study.
 If the product could be stored once opened for more than a few days by the consumer, the impact
of breaking the seal of the original packaging needs to be factored into the studies, e.g. exposure to
air, movement to/from ambient to chilled storage.
 Decide on the number and frequency of observations and/or tests that will be done, e.g. daily or
weekly. If the food has a long shelf life it may be sensible to start with less frequent observations
and increase the frequency as the expected end of shelf life approaches.
 Prepare log sheets on which to record the sequence of observations. Describe the observations to
be made and provide a scale for recording the results so it is possible to repeat or explain the trials
if required. Colour charts, pictures and descriptions of how to make the observations will be
essential to ensure this. Trained panels should be used where tests are highly subjective, e.g.
taste, smell, etc.
 Calculate the total number of samples that will be needed for the trial. If the tests involve
observation only, fewer samples will be needed than if the tests are destructive. Examine multiple
product samples (at least three product samples, and preferably more than five from each batch)
from a number of different batches when performing the trial to help to determine the variability
between and within each batch.
Step 2: Doing the study
 Obtain enough product samples for the number of observations and/or tests needed over the study
period. Samples should be randomly selected from a batch of product and be in the packaging
format available for the consumer.
 Label or number samples to allow easy identification before they are placed under selected storage
conditions.
 Carry out the study.
 Analyse the results.
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 Calculate a shelf life from the observations made, e.g. the earliest time at which mould storage
occurs, the time at which 50% of samples have an unacceptable loss of a major or several quality
attributes.
The study should be repeated with several (at least three) batches of product to identify variability within and
between batchers. If there is a large variability within and/or between batches you will need to work out how to
reduce the variability. This could be due to:
 how the product is made;
 the composition of the food;
 the type of packaging;
 the hygiene of the processing environment; and/or
 the quality of the ingredients.
Step 3: Setting the date mark: verification and review
 Determine the product date marking. This should be no longer than the number of days before
unacceptable deterioration occurs (based on the shelf life study undertaken in step 2) plus a safety
margin. A safety margin is needed because the shelf life is only an approximation and not a fixed
value and will vary from time to time. The size of the safety margin needs to take into account the
potential for the shelf life to be easily compromised by less than ideal conditions for storage,
distribution and use.
 Retention samples. Once production commences, samples should be retained, ideally from each
batch of product. These can then be checked at the end of their shelf life to confirm that the date
marking is appropriate. In the event of customer complaints that the product has spoiled before the
end of the shelf life, the retained samples can be examined to see if the complaint was justified and
an appropriate response was made, e.g. review processing records, review date marking.
 Monitor customer complaint records. Review on a regular basis for trends and evidence of shelf
life failures, e.g. impact of seasonal conditions, distribution chain effects, retailers, etc.
 Repeat the shelf life tests if there are major changes made to the product composition,
ingredients, processing or packaging to ensure that the shelf life has not been compromised by the
changes.
If you do not have suitable facilities or expertise to undertake shelf life studies, seek help from commercial
service providers.
7.3 Indirect methods for ‘best-before’ date marking
The direct methods to determine the shelf life can take too long for some products and can be costly. An
alternative is to use indirect methods such as predictive models to predict the shelf life. This information can
be used in parallel with ongoing observation of how the product performs in the market and the nature of
customer complaints.
Products where chemical changes are critical
Predictive models and calculations can be used to predict the shelf life of some types of food products, such
as pickles and sauces. These require technical expertise if they are to be applied correctly and so the
appropriate experts should be consulted.
Products where microbiological spoilage is critical
Predictive models can be used to predict the growth, survival and non-thermal inactivation of microorganisms.
Many of these models are for pathogenic bacteria but there are some models for specific spoilage issues. The
limitation of the models is that the conditions of the food must be the same as those in the model, otherwise
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they will not be applicable. The models require detailed knowledge of compositional factors such as pH and
water activity which affect the growth of microorganisms.
Refer to section 11.5 for further information on predictive models, how they work and can be applied.
7.4 When there is significant nutrient loss and a ‘use-by’ date is
required
This can be determined in the same way as for a ‘best-before’ date (section 7.2) but the focus of the study will
be the characteristic of concern, e.g. the time taken for the level of a vitamin to go below the level indicated on
the label. It will be important that these studies replicate the normal storage conditions of the product.
Manufacturers may choose to reformulate the products by increasing the amount of the nutrient added
(provided this does not exceed tolerable daily intakes or maximum levels permitted by the Code) which will
compensate for amounts lost during storage, allowing for the extended shelf life of a product to be retained.
7.5 When there is potential for growth of a pathogen and a ‘use-by’
date is required
Challenge studies
If pathogenic microorganisms could be present at low levels in the product and they could grow during the
shelf life of the product, it is important to know how fast they can grow and to what level. The best information
on growth comes from challenge studies where the food is inoculated with a cocktail of several strains of the
pathogenic microorganism and then tested at intervals to see if the bacteria increase in number. This will
establish a growth curve (see Figure 2). If the pathogen levels could reach unsafe levels before the food
shows significant spoilage which would put the customer off eating it, then a ‘use-by’ date will be essential.
(Refer to Figure 2, scenario A).
Where L. monocytogenes is a hazard reasonably likely to occur in a ready-to-eat (RTE) food, Standard 1.6.1
of the Code provides microbiological limits. The applicable limit depends on whether or not the RTE supports
the growth of L. monocytogenes. Some of these RTE foods do not receive a listericidal process during
processing and the safety of the product depends upon minimising or reducing contamination throughout the
food chain, limiting growth of L. monocytogenes and/or reducing the shelf life. These foods include cold-
smoked fish and prepared salads. There may occasionally be low levels of L. monocytogenes present but
these are not a risk if the growth of the bacteria can be minimised or limited. Where operators can provide
evidence that the growth of L. monocytogenes will not exceed 100 cfu/g during the stated shelf life, a limit of
100 cfu/g applies for the purpose of, Standard 1.6.1. Evidence may include:






the characteristics of the food and the factors that minimise or reduce the growth of L. monocytogenes,
e.g. pH, water activity, storage temperature, etc.;
historical information on similar or related food products;
information from scientific literature and risk assessments;
challenge studies;
predictive models; or
a combination of these approaches.
Where the characteristics of the food or the storage conditions permit the bacteria to grow, then further
evidence will be required using predictive models or a challenge study to demonstrate and to verify that the
‘use by’ date is appropriate.
Figure 3 outlines the steps of a challenge study. Several detailed protocols are available for conducting
challenge studies (see section 11.6).
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Important points that must be included when designing a challenge study are:
 the food tested must be the same as that supplied to the consume;
 the inoculation level should reflect the purpose of the study i.e. when a ready-to-eat food is
contaminated with a small number of pathogens, are they able to grow to unsafe levels during the
expected shelf life of the food and the application of this information to an appropriate date mark;
 when inoculating the food with the bacteria, the method of inoculation should reflect the way
contamination is likely to occur, e.g. CCP failure or cross-contamination of food;
 the inoculated food should then be packaged as intended for retail sale or the packaged product
may be inoculated, taking care that the integrity of the packaging is not compromised;
 incubation temperatures should reflect the anticipated range of temperatures conditions and
possible consumer abuse temperature (see Table 2 in Listeria monocytogenes Challenge Testing
of Ready-to-Eat Refrigerated Foods (Health Canada) http://www.hc-sc.gc.ca/fn-
an/legislation/pol/listeria_monocytogenes-test-eng.php);
 for foods where there are potentially variable levels of spoilage or other bacteria present, it may be
helpful to monitor their levels also, as they may impact on the rate of growth of the pathogens; and
 documentation of all aspects and details of the challenge study.
Figure 3: The steps of a challenge trial
CHALLENGE STUDIES
Preparation of cells
Multiple strains
Growth media (non-selective)
Stationary phase
Temperature adjusted
Inoculation of food
10 – 30 cfu/g
Triplicate (different lots)
Packaged as intended for
sale
Documentation of results
Detailed methodology
Raw data and analyses
Interpretation/conclusions
Storage
Temperatures?
Static/dynamic
Testing
Selective media
Enumeration/enrichment
Sampling
Frequency (t=0, t=1, t=2,
t=?), 1.5 shelf life
Diagram provided by FSANZ (2013)
Predictive modelling of growth of bacteria in food
An alternative to challenges studies is to use predictive models. Entering the characteristics of the food into
the model will either probability of growth or provide a growth curve. While several of these models have been
refined in recent years, it would always be recommended that a challenge study is also undertaken to confirm
that the model reflects your product accurately. Section 11.5 lists a number of the predictive models available.
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7.6 Shelf life of composite foods
When calculating the shelf life of a product that is made up of two or more individual separate food
components, e.g. yoghurt with a fruit sauce layer or a ready meal, the shelf life of each food must be taken
into account when assigning a date mark. The shelf life should not exceed the shortest value.
Where the foods have been blended together the shelf life for the composite food will be affected by the
characteristics of the individual components. If the components have similar characteristics, e.g. several types
of cereal blends, the shelf life of the composite food would usually reflect that of the component food with the
shortest shelf life. However if the components are very different, such as a salad with dressing, the shelf life of
the components is no longer relevant and a shelf life for this new food needs to be established (refer to
section 9).
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8 Date marking changes
The shelf life of a food may change if it is taken from its original packaging. While it is acceptable to
repackage a food and place a new label with an accurate date mark on it, there are certain legal requirements
that must be met to change the date mark.
8.1 When a date mark may need to be changed
The shelf life reflected by the date mark applied by a food manufacturer takes into account anticipated storage
conditions of the product until it is used. If these change, for example the storage temperature is higher, or the
humidity increases, or the packaging is damaged or opened, the product is no longer being kept under the
conditions expected by the manufacturer. The shelf life will have changed and the original date mark may also
need to be changed. Examples of this include chilled food that is later frozen (food in original packaging – see
section 8.3); and bulk products that are divided into smaller lots (repackaged food – see section 8.4).
8.2 The regulatory requirements
The Code, section 1.2.1—22 prohibits altering a label unless certain conditions are met. It states;
“1.2.1—22 Prohibition on altering labels
(1) A person who sells a food for sale that is packaged, or deals with a packaged food for sale
before its sale, must not deface the label on the package unless:
(a) the *relevant authority has given its permission; and
(b) if the relevant authority has imposed any conditions on its permission—those conditions have
been complied with.
(2) Despite subsection (1), a person who sells a food that is packaged, or deals with a packaged
food before its sale, may re-label the food if the label contains incorrect information, by placing a new label
over the incorrect one in such a way that:
(a) the new label is not able to be removed; and
(b) the incorrect information is not visible.
(3) In this section:
deface includes alter, remove, erase, obliterate and obscure.”
Food with a ‘use by-date’ must not be sold beyond its ‘use-by’ date
Food with a ‘best-before’ date can legally be sold past its ‘best-before’ date, provided that the safety and
suitability of the food is maintained. Date marks (as with all label information) cannot be changed without the
permission of the relevant authority.
* In New Zealand the ‘relevant authority’ is the Ministry for Primary Industries (MPI).
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8.3 Applying for permission to change a date mark
To change a date mark an application must be submitted to MPI as the relevant authority. Anyone (a food
manufacturer, importer, distributor or retailer) may apply to change a date mark. If the applicant is not the food
manufacturer they will need to obtain supporting information from the food manufacturer about the product’s
shelf life to show continued safety and suitability of the food.
Sufficient information will need to be submitted with the application to enable the relevant authority to
determine whether the permission can be granted. The Date Mark Alteration Application Form sets out the
information required by MPI when considering applications submitted to change a date mark. A copy of the
form can be found in section 12 and from www.mpi.govt.nz.
Additional information is required for applications to change a ‘use-by’ date (refer to Box 4 of the form).
MPI may only grant permission to alter the date mark in situations where the food will remain safe and
suitable to consume.
8.4 Examples where permission is not required from MPI to change a
date mark
Errors on labels
When there are errors on a label, e.g. the wrong year is displayed, and the food is still in the control of/held by
the food manufacturer, corrective actions can be taken without applying to MPI. For example, a re-printed
label including the correct date can be placed over the incorrect label. This corrective action should be
recorded by the manufacturer as it will provide their verifier or a Food Safety Officer with a degree of
confidence that the business understands and applies its risk based measures.
Repackaged foods
If food is removed from its original packaging, it is very unlikely to have the same shelf life as originally given
by the manufacturer. The shelf life is likely to be shorter (and very unlikely to be extended) once the original
protective packaging has been removed. When this happens:
 there is the opportunity for the product to become contaminated during handling, e.g. slicing,
portioning, repackaging;
 the temperature of the product may increase and provide conditions for microbial growth.
Contact the food manufacturer to obtain information that will accurately determine the new date mark to be
applied, before changing the date mark on the repackaged product. The manufacturer may want to know
about the conditions under which the product is to be handled once it has been removed from its original
packaging.
If slicing a product for display in a cabinet, e.g. in a deli, it is also important to ensure the shelf life is calculated
correctly, especially if a bulk product is not used in one go. For example, an opened vacuum-pack of bulk ham
is sliced and sold over several days. The shelf life of ham sliced on day three may be shorter than the shelf
life of ham sliced on day one. The increased amount of handling and time away from temperature control will
increase the risk that the remaining bulk ham will become subject to the bullet points above. The deli should
be able to show their verifier how they calculate the shelf life of ready-to-eat foods in contained in a display
unit to ensure safe products. The deli may want to label foods with a date mark or information about
storage/use but only have to provide information if a customer requests it. If the deli repackages the ham, the
packages will need to be labelled with an accurate date mark. This does not require permission from the
relevant authority provided that the original date mark has not passed.
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Further information for delis is provided in the template Food Control Plan for Food Service and Food Retail
which is available on the MPI website at: http://mpi.govt.nz/food-safety/food-act-2014/forms-and-templates/
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9 Factors that influence shelf life
Factors that influence the shelf life are either:

intrinsic; the product characteristics, e.g. acidity, moisture content, etc.; or

extrinsic; external characteristics, e.g. storage temperature, packaging, etc.
9.1 Intrinsic and extrinsic factors
Even if two products look similar, their shelf life can be quite different. It is not safe to take the shelf life from
one and apply it to the other. You need to know what has occurred during manufacture and understand the
factors that will influence its storage characteristics before being able to arrive at an appropriate shelf life for
your food.
Characteristics of the food itself (i.e. intrinsic)
The intrinsic factors that impact on its shelf life include:
 The nature and quality of the raw materials. Good quality raw materials with low numbers of
microorganisms present will help ensure products with a consistently acceptable shelf life. If raw
materials could sometimes be heavily contaminated, this needs to be taken into account during
processing. For example, fresh produce harvested in wet conditions may need a further wash to
achieve the same and consistent shelf life as fresh produce harvested on a dry day. If the numbers
of spoilage microorganisms or pathogenic bacteria are highly variable, this may impact on the
process and consequently the shelf life. In this case, consider setting microbiological limits
(specifications) on raw materials and ensure that the process is validated using worst case
conditions.
 Product formulation including the use of preservatives. Mould and bacterial growth can be
inhibited or slowed down by removing moisture. Removing, substituting or modifying ingredients in
some way may allow microorganisms to grow where previously they were inhibited. Replacing
sugar with an artificial sweetener; using a reduced-acid vinegar; changing the type of acid;
removing nitrates from a processed meat; reducing the amount of added salt can all reduce the
effectiveness of hurdles introduced to control microorganisms and so change the shelf life of a
product.
 Product structure. Liquids and semi-solid foods will usually have a homogeneous composition,
but many products do not, including composite foods. Moisture and flavours will migrate between
layers, while coatings and surface treatments can either restrict or enhance the spoilage potential.
For example: herbs and spices on the surface of a pâté may grow mould, but a layer of aspic over
the herbs will exclude air and prevent mould growth; the pastry crust covering a meat pie will make
the content anaerobic, but will allow bacterial spores such as Clostridium perfringens – commonly
associated with meat – to germinate and grow; however anaerobic conditions are less likely with a
potato topping. It is important to understand the structure of your products, for example where there
is the potential for anaerobic pockets to form these could provide the right environment for
anaerobic bacteria to grow.
 Oxygen availability and redox potential within the food. This can have a major effect on which
sorts of spoilage and pathogenic microorganisms will grow on the food. This also impacts on
oxidation-reduction reactions which cause rancidity, loss of vitamins, browning and flavour changes
resulting in product deterioration. Moulds need oxygen to grow and so are usually found on food
surfaces but will grow in crevices within food.
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More information on intrinsic factors of specific foods is available at the following site:
http://www.fda.gov/Food/FoodScienceResearch/SafePracticesforFoodProcesses/default.htm
External factors (i.e. extrinsic) to the food
These will also have an impact on shelf life and include
 Processes applied to the food. It is important to validate the process using the worst case
conditions, because the more bacteria in the raw materials, the greater the number of bacteria that
will survive and shorten shelf life. While retort processes can be used to inactivate the most heat-
resistant organisms, milder heat processes will inactivate only some bacteria and a proportion will
survive. Generally the more intense the process, the longer the shelf life can be.
 Cooling methods applied to heat treated products. Some spoilage and pathogenic bacteria
produce spores that may not only survive but may be activated during the heating process. If the
food is not cooled rapidly after the heat treatment, these activated bacteria may increase rapidly in
the warm food and cause spoilage and in some cases food poisoning. This is important for meat
where Clostridium perfringens can be a concern, whereas for dairy processing, cereals and baked
goods Bacillus spp. are more likely to be associated with these products. Cooling can be hastened
by techniques such as spreading the product to be cooled into a thin layer, dividing into smaller lots
or blast chilling.
 Type of packaging including the gaseous environment. Packaging will have a primary role of
protecting a food after processing but may also be used to extend the shelf life. If the gaseous
environment is changed, e.g. vacuum packing or gas flushing, this will favour the growth of certain
pathogenic bacteria and spoilage bacteria, while inhibiting the growth of microorganisms that
require oxygen (including moulds).
 Storage temperature (i.e. ambient, chilled or frozen). While frozen storage will stop the growth of
all but a very few spoilage microorganisms, chilling will only slow growth. A number of spoilage
microorganisms and cold-tolerant bacteria will actively grow under chilled conditions. Their growth
will usually be slower than would occur during ambient storage.
 Conditions during distribution, storage, retail display and storage by the consumer. At any
point in the product’s shelf life, it may be exposed to conditions that will lead to the food showing
signs of deterioration and a shortened shelf life. These conditions include elevated or fluctuating
temperatures, U.V. light, high humidity, freezer burn, vibrations, etc.
Table 1 provides a brief overview of the impact that processes applied to food may have on the
microbiological safety and spoilage of food.
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Table 1: Impact of processing on microbiological food safety and shelf life
Processes applied to foods
Effect on microorganisms
Vegetative bacteria (either
spoilage or pathogenic) and
mould spores and yeasts
Washing of raw materials, e.g.
plant material
Numbers present are reduced
Bacterial spores (cause spoilage or
food poisoning depending on type)
Numbers present are reduced
May improve food safety by physically reducing
pathogenic bacteria present. Levels may increase if
the water is poor quality, not changed frequently or
if too great a volume of fresh produce is washed at
the same time
Cooking – includes baking
Numbers present are reduced to
very low levels
No decrease in numbers and the process
may activate germination of the spores
Vegetative pathogenic bacteria inactivated using a
validated process.
Spores will survive and may germinate to make the
food unsafe if it is not consumed or cooled
immediately.
Some but not all pre-formed bacterial toxins will be
inactivated
Cooling of cooked foods
Pasteurisation of liquids or
solids
UHT/aseptic processing
Minimal reduction in numbers
Potential for spores to germinate and grow
if cooling is slow or uncontrolled
Numbers are reduced to low levels No decrease in the number of spores and
may be activated
Inactivates most vegetative
bacteria and yeasts/moulds
Inactivates most spores except for a few
heat resistant spoilage types (however
these are usually unable to grow in the
anaerobic environment at ambient
temperatures in the container)
Canning and retorting
Inactivates most vegetative
bacteria and yeasts/moulds
Inactivates most spores except for a few
heat resistant spoilage types (however
these are usually unable to grow in the
anaerobic environment at ambient
temperatures)
Spore-forming pathogenic bacteria will germinate if
cooling is not managed correctly and the food may
become unsafe
Significant improvement provided that the time and
temperature applied is appropriate and cooling
managed correctly
Foods become low risk
Variable. Washing may damage surfaces
which would allow microbial growth and
decrease shelf life
Extended (providing that cooling is
managed) unless spores are able to
germinate and grow post-cooking or baking
Impact on food safety
Impact on length of shelf life due to
spoilage
Decreased if cooling is not managed
correctly and any spore-forming bacteria
present germinate
Extended provided that cooling is managed
correctly
Significant extension
Foods become low risk
Significant extension
Ministry for Primary Industries
Page 31 of 42

Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
Processes applied to foods
Effect on microorganisms
Vegetative bacteria (either
spoilage or pathogenic) and
mould spores and yeasts
Microbiological hurdles i.e.
multiple factors such as high
salt, lowering of pH, nitrates,
high sugar, fermentations,
decreased moisture/drying
Addition of preservatives
including some spices and
herbs1
Salting, drying and pickling
Packaging and gaseous
atmosphere including
excluding air with oil2
Storage temperature
Variable effect depending on the
specific microbiological hurdles
applied
Prevents increases of a specific
range of microorganisms
Bacterial spores (cause spoilage or
food poisoning depending on type)
No decrease in numbers but spores may
be inhibited from germinating
Combinations of hurdles will vary in ability to
inactivate or inhibit growth of pathogenic bacteria
Impact on food safety
Impact on length of shelf life due to
spoilage
Extended as long as conditions remain
unchanged
No decrease in numbers but spores may
be inhibited from germinating
Improves food safety by inhibiting growth of a
specific range of pathogenic bacteria
May provide some shelf life extension by
inhibiting spoilage.
May ensure shelf life met by preventing
growth of contaminants introduced into
product during use
Will inhibit the growth of most
pathogenic bacteria and some
spoilage microorganisms
Will inhibit the growth of many
pathogenic bacteria and spoilage
microorganisms. Could promote
growth if not careful
Chilled (less than 5˚C) –
decreases growth.
Frozen – stops growth of most
microorganisms
No decrease in numbers but spores may
be inhibited from germinating
Variable – depends on the gaseous
requirements of any spore-forming bacteria
that could be present
Chilled (less than 5˚C) – stops growth
except for cold-tolerant.
Frozen – variable – stops the germination
and growth of most bacterial spores whilst
for other spores the numbers will decrease
Vegetative forms of pathogenic bacteria may
survive for a while but will usually die off over time
Pathogenic bacteria could grow if conditions are
suitable. Gaseous environment may favour
pathogenic bacteria by suppressing growth of
spoilage microorganisms that would inhibit
pathogenic bacteria
Chilled (less than 5˚C) – cold-tolerant pathogenic
bacteria will be a concern if present.
Frozen – stops growth of most pathogenic bacteria
and some will decrease in number over time
Extended as long as conditions remain
unchanged
Extended as long as conditions remain
unchanged
Extended for chilled; major extension for
frozen
1 Herbs and spices used as preservatives must be free of pathogenic bacteria and spoilage microorganism or they will adversely impact on the food safety and shelf life of the food
2 The gaseous environment created may favour the growth of some pathogenic bacteria and spoilage microorganisms that do not grow in air or favour low oxygen environments. Of particular concern
are Clostridium botulinum spores which may be present on some seafood and plant material harvested from locations where this bacterium is found. Clostridium botulinum is not considered to be a
major concern for ingredients and raw materials originating from New Zealand soil or locally sourced seafood.
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
10 Pathogenic bacteria associated with ready-to-eat chilled
foods
There are four cold-tolerant bacteria that it is essential to consider when determining a date mark for a chilled
ready-to-eat food (identified in Figure 1, step 5 of the decision tree). If any of these pathogenic bacteria are
reasonably likely to be present in the food at the end of processing, it is important to consider whether the
storage conditions and time will result in the bacteria growing to unsafe levels during the shelf life. A ‘use-by’
date will be needed if there is the potential for this to occur to ensure that the consumer does not eat the food
beyond this date.
Of the four cold-tolerant pathogenic bacteria listed, the most relevant to New Zealand produced food is
Listeria monocytogenes. For information on all the pathogenic bacteria, refer to the Pathogen Data Sheets
published on the MPI website together with the information provided below:
http://www.foodsafety.govt.nz/science-risk/hazard-data-sheets/pathogen-data-sheets.htm
10.1 Listeria monocytogenes
Listeria monocytogenes Pathogen Data Sheet
Illness that could result if present in food
Food containing large numbers of Listeria monocytogenes may cause listeriosis when consumed. Consumers
most susceptible to listeriosis are pregnant women, babies, the elderly and people with weakened immunity.
Listeriosis is fatal in about 20 to 30% of the cases.
How it gets into food
Listeria monocytogenes is widespread in the environment and can be introduced into the food at any stage
from raw ingredient to the end of processing if the opportunity exists. It will therefore be important to keep
levels as low as practicable in raw ingredients and in the processing environment.
Listeria is a frequent contaminant of wet processing environments and forms a biofilm inside and on the
surface of all types of processing equipment. Biofilms are layers of the bacteria which attach to surfaces and
become hard to remove. However bacteria can detach from the biofilm and contaminate the food being
processed. In the processing environment drains are a potential source of contamination.
It is vital to prevent ready-to-eat foods from becoming contaminated once they have been processed. Where
this potential exists it is essential that post-processing activities are separated from those that occur prior to a
listericidal process. Separation may be achieved through the use of physical means, by distance or by time.
The hygiene within the processing area is strictly controlled.
Risk management options
Pasteurisation
Raw materials and ingredient
controls and specifications
Effectiveness in controlling Listeria monocytogenes
Susceptible to commonly used time/temperature combinations –
see the appropriate pathogen data sheet for details
For ingredients that could be heavily contaminated, apply incoming
raw material specifications at levels that processing can eliminate;
reject or apply additional controls to incoming raw materials
harvested under conditions that could result in elevated levels, e.g.
milking animals with mastitis, vegetables harvested in bad weather
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
Formulation of food
Will not usually grow in foods with pH less than 4.4, water activity
less than 0.92. Combinations of hurdles will also be effective, e.g.
pH 5.0 with a water activity of less than 0.94; minimum salt level of
3.5% in the aqueous phase throughout the food
Gaseous environment of packaging Listeria will grow both in air and in the absence of air (vacuum
packaging); will grow at 30% CO2 but not at 100%
Presence of spoilage or other
microorganisms, e.g. fermentative
Cold storage
Preservatives
Poor competitor so will not grow well in fermented foods and when
spoilage organisms present
Chilled storage (less than 5˚C) only reduces growth rate; growth
stops during frozen storage but they will survive freezing
Many commonly used preservatives will prevent growth but
effectiveness should be confirmed. May be most effective when
used with other inhibitory factors, e.g. low pH, fermenting
microorganisms
Pasteurisation of food in retail
packs
Processing environment
For processed food, especially where competing bacteria have been
eliminated, post-processing contamination is a concern. A validated
treatment, such as pasteurisation in-pack will eliminate this
contamination
For foods vulnerable to contamination, a Listeria Management
Programme with a well-designed environmental monitoring
programme will identify when there is the potential for contamination
to occur
Refer to the MPI Guidance for the control of Listeria monocytogenes in ready-to-eat foods
http://www.foodsafety.govt.nz/science-risk/programmes/hazard-risk-management/listeria.htm
10.2 Clostridium botulinum
Clostridium botulinum Pathogen Data Sheet
Illness that could result if present in food
Toxins released into the food during bacterial growth are powerful neurotoxins and may cause botulism which
is very often a fatal illness.
How it gets in to food
The bacteria occur in the soil and so are commonly associated with plant material. They may also be found in
association with seafood. Only some strains are of concern for refrigerated foods. These strains are identified
as non-proteolytic (Group II) C. botulinum Types B, E and F. While there is one recorded event in New
Zealand where two sisters were diagnosed as having botulism from eating incorrectly preserved mussels and
watercress, C. botulinum was not isolated from the food. Previous surveys of the New Zealand environment
have not detected C. botulinum Type E, a hazard for smoked fish, nor C. botulinum Type A. Other strains of
C. botulinum have been isolated in New Zealand, but are not human pathogens (types C and D). Whilst New
Zealand ingredients are considered unlikely to be contaminated with human pathogenic C. botulinum,
ingredients and raw materials imported from other countries could carry spores of C. botulinum. C. botulinum
grows only in the absence of air (anaerobic) so is only an issue in foods in sealed packaging from which air is
excluded, e.g. vacuum packaging, foods packed in oil, canning and retorting.
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
Risk management options
Heat treatment
Effectiveness in controlling cold-tolerant (non-proteolytic)
Clostridium botulinum
Both spores and vegetative cells of cold-tolerant C. botulinum can
be inactivated by heat processing, e.g. heating to 90°C for 10 min
(unlike other types of Clostridium botulinum which produce heat
resistant spores). Toxins present in food can be inactivated by
heating (D 74°C less than or equal to 3 minutes)
Raw materials and ingredient
controls and specifications
While there are now simple cultural or molecular tests that suggest
the presence of C. botulinum vegetative cells and spores in food
samples, confirmation requires demonstration of the presence of
genes for the toxins and co-factors, as detected by polymerase
chain reaction (PCR) or next generation sequencing (NGS), and
confirmation by mouse bioassay of toxin production. Review the
source of critical materials from countries where C. botulinum could
occur
Formulation of food
Will not usually grow in foods with pH less than 5.0 but this may
then encourage spores to form; minimum water activity for growth
0.97; minimum salt level of 3.5% in the aqueous phase
Gaseous environment of packaging Will not grow in air; will grow in the absence of air, i.e. vacuum
packaging, retorted and canned product; growth rate reduced in
100% CO2
Presence of spoilage or other
microorganisms, e.g. fermentative
Cold storage
Preservatives
Pasteurisation of food in retail
packs
Will be inhibited by the presence of fermentative microorganisms
Will not grow at temperatures less than 3˚C or during frozen storage
Nitrites/nitrates most commonly used preservatives in meat are
effective only in combination with lowered pH and fermenting
microorganisms
Pasteurisation in-pack will not inactivate spores
A useful source of information from the U.K. is the Food Standards Agency Guidance on the safety and shelf
life of vacuum and modified atmosphere packed chilled foods with respect to non-proteolytic Clostridium
botulinum:
http://www.food.gov.uk/multimedia/pdfs/publication/vacpacguide.pdf
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
10.3 Bacillus cereus
Bacillus cereus Pathogen Data Sheet
Illness that could result if present in food
B. cereus-associated foodborne illness occurs as two distinct intoxication syndromes: emetic and diarrhoeal.
Recovery is rapid for both syndromes, usually within 12-24 hours of consuming food contaminated with large
numbers of the bacteria which grow and produce toxin. There are usually no long-term effects.
How it gets into food
Widely found in the environment and associated with raw ingredients including milk, so where they are a
concern, the levels need to be as low as possible. Only a very few strains of B. cereus and other related
Bacillus species are both pathogenic and cold-tolerant and so would be a potential issue for chilled ready-to-
eat foods and there is little evidence that these strains of B. cereus are widely found in New Zealand.
Risk management options
Heat treatment
Effectiveness in controlling cold-tolerant Bacillus cereus
Both spores and vegetative cells can be inactivated by heat
processing but the inactivation of spores will require elevated
temperatures. If vegetative cells are allowed to grow and produce
toxins, the toxins are not easily destroyed by heat
Raw materials and ingredient
controls and specifications
Formulation of food
Spores associated with starchy foods and dairy ingredients. May
apply specifications for aerobic spore. Spores survive well in dry
ingredients
Will not usually grow in foods with pH less than 4.5 and water
activity less than 0.91
Gaseous environment of packaging Will grow in presence or absence of air, i.e. in most modified
atmosphere packaging (MAP) but toxin production only when
oxygen present
Cooling of foods post-processing
Spores that survive a heat process, e.g. cook step will become
vegetative cells and grow in numbers if the cooling stage is
extended. Rapid controlled cooling therefore vital so that toxins are
not formed by the growing cells
Cold storage
Preservatives
Pasteurisation of food in retail
packs
Processing environment
Few strains will grow at temperatures less than 7˚C or during frozen
storage
Vegetative cells inhibited by a number of preservatives, e.g. sorbate
and benzoate
Pasteurisation in-pack will not inactivate spores
Can form biofilms in processing equipment and become difficult to
remove; ensure cleaning programme capable of removing and
preventing biofilm formation
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
10.4 Yersinia entercolitica
Yersinia enterocolitica Pathogen Data Sheet
Illness that could result if present in food
Infection can cause diarrhoea and abdominal pain one week after consuming contaminated food. Symptoms
may be mistaken for appendicitis. The illness is usually self–limiting but may be more severe and complicated
in children under five years and other vulnerable consumers.
How it gets into food
The bacteria are transmitted from food animals and so can be contaminants of pork, beef, lamb and poultry.
Fresh produce may become contaminated from the environment or directly from animals and possibly birds.
While food has been suggested as a source of infections in New Zealand, cases have not been linked to
processed foods.
Risk management options
Heat treatment
Raw materials and ingredient
controls and specifications
Formulation of food
Fermentation and drying
Effectiveness in controlling cold-tolerant Yersinia
enterocolitica
Readily inactivated by heat processing including pasteurisation
Associated with raw meat, including offal – contamination of
carcasses may be reduced by certain practices; potential to be
associated with plant material reduced by good agricultural practices
pH variable and may grow in foods with pH 4.2 and does not grow if
water activity less than 0.96
In meat products, survival will be inhibited in a well-controlled and
effective fermentation or drying process
Gaseous environment of packaging Will grow in presence or absence of air, i.e. in most MAP packaging
Cold storage
Will grow at temperatures as low as -1.3˚C
Preservatives
Pasteurisation of food in retail
packs
Processing environment
May be inhibited by preservatives but data limited
Pasteurisation in-pack will inactivate
Evidence that contaminated water used in processing has been a
source of contamination in some outbreaks
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
11 Useful links
11.1 Shelf life and date marking in general
 MPI Food Labelling Guide
http://www.foodsafety.govt.nz/elibrary/industry/nzfsa-food-labelling-guide/
 FSANZ user guide to date marking
http://www.foodstandards.gov.au/code/userguide/Pages/datemarking.aspx
 Validation of Product Shelf life. Guidance note (Food Safety Authority of Ireland) (Includes a
discussion of intrinsic and extrinsic factors influencing the growth of microorganisms)
https://www.fsai.ie/publications_GN18_shelf-life/
 Code of Hygienic Practice for Refrigerated Packaged Foods with Extended Shelf Life CAC/RCP
46-(1999) (Codex)
http://www.codexalimentarius.net/download/standards/347/CXP_046e.pdf
 Evaluation and Definition of Potentially Hazardous Foods (USA)
http://www.fda.gov/food/foodscienceresearch/safepracticesforfoodprocesses/ucm094141.htm
11.2 Foodborne disease surveillance
http://www.foodsafety.govt.nz/science-risk/human-health-surveillance/
11.3 Listeria monocytogenes
 Listeria monocytogenes Pathogen Data Sheet
 Shelf life in relation to L. monocytogenes guidance for food business operators (U.K.)
http://www.food.gov.uk/business-industry/manufacturers/shelf-life-storage/readytoeat
 Technical guidance on Listeria monocytogenes shelf-life studies for ready-to-eat foods (EC)
http://eurl-listeria.anses.fr/en/minisite/listeria/eurl-lm-technical-guidance-document-conducting-
shelf-life-studies-listeria
 Guidance document on Listeria monocytogenes shelf-life studies for ready-to-eat foods, under
Regulation (EC) No 2073/2005 of 15 November 2005 on microbiological criteria for foodstuffs
http://www.fsai.ie/uploadedFiles/Food_Businesses/Microbiological_Criteria/EU_Guidance_listeria_
monocytogenes2008.pdf
11.4 Clostridium botulinum
 Clostridium botulinum Pathogen Data Sheet
 Clostridium botulinum in New Zealand marine sediments: Very low prevalence of Clostridium
botulinum in New Zealand marine sediments (368 KB PDF)
http://foodsafety.govt.nz/elibrary/industry/Clostridium_Botulinum-Science_Research.pdf
 Guidance on the safety and shelf-life of vacuum and modified atmosphere packed chilled foods
with respect to non-proteolytic Clostridium botulinum (U.K. Food Standards Agency)
http://www.food.gov.uk/multimedia/pdfs/publication/vacpacguide.pdf
 Information sheet for manufacturers of vacuum packed chilled foods (U.K. Food Standards Agency)
http://www.food.gov.uk/multimedia/pdfs/publication/vacpack0708.pdf
Ministry for Primary Industries
Page 38 of 42

Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
11.5 Predictive modelling
 Instructions on how to use predictive modelling and the main models can be found at the USDA
Food Safety & Inspection Service (FSIS) and the USDA Agricultural Research Service (ARS)
Predictive Microbiology Information Portal (PMIP). This portal is available from:
http://portal.errc.ars.usda.gov/
 ComBase – includes Combase Predictor (previously Growth Predictor and Food MicroModel) with
growth or inactivation models for 12 foodborne pathogenic bacteria, a growth model for Brochothrix
thermosphacta and Perfringens Predictor.
http://www.combase.cc
 Pathogen Modeling Program – includes more than 40 models for different pathogenic bacteria.
Model allows growth or inactivation of pathogenic bacteria to be predicted for different
combinations of constant temperature, pH, NaCl/aw and, in some cases, other conditions such as
organic acid type and concentration, atmosphere or nitrate.
http://www.ars.usda.gov/services/docs.htm?docid=6786
 Food Spoilage and Safety Predictor – developed by the Danish Technical University. The FSSP
software predicts shelf life and growth of bacteria in different fresh and lightly preserved seafood
e.g. the effect of product temperature profiles recorded during storage and distribution by data
loggers.
http://fssp.food.dtu.dk/
 Sym’Previus – an extensive French decision support system that includes (i) a database with
growth and inactivation responses of microorganisms in foods and (ii) predictive models for growth
and inactivation of pathogenic bacteria and some spoilage microorganisms
http://www.symprevius.net
 Shelf Stability Predictor – developed by the Center for Meat Process Validation at the University
of Wisconsin – Madison to predict the growth of Listeria monocytogenes and Staphylococcus
aureus on ready-to-eat meat products as a function of pH and water activity.
http://meathaccp.wisc.edu/ST_calc.html
 FORECAST – is a shelf life prediction service for chilled foods where predictions for Pseudomonas
spp., Bacillus spp., Enterobacteriaceae, Yeast and Lactic acid bacteria are available. FORECAST
is available from Campden BRI, Chipping Campden, Gloucestershire, GL55 6LD, UK, phone
+44(0)1386 842071, [email protected] or [email protected]
http://www.campdenbri.co.uk/services/predictive-microbiological-models.pdf
 Corbio™ Listeria Control Model 2012 – predicts the growth of Listeria monocytogenes in food
products, with the use of eight food characteristics. https://lcm.purac.com/Challenge testing
11.6 Challenge modelling
 Evaluation and Definition of Potentially Hazardous Foods – Chapter 6. Microbiological Challenge
Testing (USFDA)
http://www.fda.gov/Food/FoodScienceResearch/SafePracticesforFoodProcesses/ucm094154.htm
 Listeria monocytogenes Challenge Testing of Ready-to-Eat Refrigerated Foods (Health Canada)
http://www.hc-sc.gc.ca/fn-an/legislation/pol/listeria_monocytogenes-test-eng.php
Ministry for Primary Industries
Page 39 of 42

Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
 Clostridium botulinum Challenge Testing of Ready-to-Eat Foods (Health Canada)
http://www.hc-sc.gc.ca/fn-an/legislation/pol/sop-cbot-eng.php
 Challenge Testing of Microbiological Safety of Raw Milk Cheeses: The Challenge Trial Toolkit. This
report provides information about the conduct of challenge trials for raw milk cheeses and is a
useful background on the conduct of challenge trials in other foods, including the need to
characterise the microorganisms used.
http://foodsafety.govt.nz/elibrary/industry/challenge-trial-toolkit/index.htm
Ministry for Primary Industries
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Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
12 Date Mark Alteration Application Form
Date Mark Alteration Application Form may be located and printed on the website administered by MPI.
Date Mark Alteration
Application Form
.
.
1. Applicant details
Legal name
Trading name
Head office address
Ministry for Primary Industries
Manati Ahu Matua
Non fh k
Postal address
(idifferent from absve)
Telephone
Fax
Email
Pape afbusiness
Product detail
Product sponsor (the food Business with primary
cesaausiliy, for the supply of a food product)
Product name
Type/Brand
Pack size & amount of
product affected
Lot ID/Date mark
Change request details
Reason alteration is
being sought
Product storage historv
Proposed alteration and
who will apply it
Is this request for a negulat
or one-off event?
4. Use-by date alteration
If applying for change to use-by date please complete this box. If not please goto Box 5.
Please attach information to support the use-by label alteration. This information needs to be sufficient to
enable the relevant authority to determine that food safety will not be compromised. Information mayinclude
\\
thefollowing:
.
shelf life study information;
.
.
impact of storage conditions on pathogenic fe.g. Listeria monocytogenes) growth and/or survival;
other relevant product characteristics.
Manfacture r
Distributor
Retailer
Importer
Other
Ministry for Primary Industries: May2016
Date Mark Alteration Application Form ® Page 1
Ministry for Primary Industries
Page 41 of 42
w
N
he =e
a
_o

Guidance Document: How to Determine the Shelf Life of Food
9 June 2016
5. Product Sponsor
The product sponsor has been contacted and supports this applicatioh
= (gig, tick one}
YES
NO
\5 lfYES. complete the information below. Please attach certification from the sponsor verifvine support.
Sponsors contact
Sponsor’s trading name
aod business address
Name/Role of contact
Postal address
lif different fram abobe
Telephone
Fax
Email
‘
6. Product traceability
Please describe how unique
Jat identification will be
maintained
Locations where this product
will be sold/product
distribution.
Anolicant Signature:
Date:
7. Send completed form to: [email protected]
Postal address:
MPI
PO Box 2526
Wellington 6140
Relevant authority (MPI) use only
Dedsion:
Relevant parties notified:
Relevant authority
Date:
(MPI) signature
Ministry for Primary Industries: May 2016
Date Mark Alteration Application Form
Page 2
Ministry for Primary Industries
Page 42 of 42