Heat Treatment Training Course

Pasteurization is process of heat treatment using a combination of temperature and time and/or the partial/full sterilization of a product, such as milk, liquid egg, beer, wine, juice to make it safe for consumption. This minimizes the risk of illness from pathogens such as Human Tuberculosis, Salmonella, Coxiella Burnetii, Campylobacter jejuni, Listeria, Thermoduric bacteria and simultaneously improves the product’s quality and shelf-life.

The process was invented by Louis Pasteur in the late 1800s. Pasteur identified the exact time and temperature to kill the harmful microorganisms in the wine that caused illness without changing its taste. He patented the process and called it pasteurization. This process was then applied to other products such as dairy, food products, and beverages across the globe.

The process of heating every particle of product to the minimum required temperature continuously for the minimum required time in equipment that is properly designed to minimize the food safety risk to the product.

Pasteurisation is rapidly heating milk to a temperature of no less than 72°C/161°F and retaining it at that temperature for no less than 15 seconds, or rapidly heating milk to a temperature of no less than 63°C/145°F and retaining it at that temperature for no less than 30 minutes.
Code of Practice (COP- Source MPI) / Code of Federal Regulations (CFR Title 21 – Source FDA)

In the context of a batch or vat, a pasteurizer is not just one piece of equipment it’s a collection of equipment it’s a system.

Pasteurizer systems include but is not limited to:

• A jacketed vessel
• Proper outlet valve of solid stainless steel construction
• Thermometers. There are normally at least three thermometers
• A recording chart
• An agitatorCode of Federal Regulations –  Source FDA)

In 1863, Louis Pasteur received a letter from one of Napoleon III’s aides, commissioning him to study the spoilage and “diseases of wine”—a matter of great urgency in France, where wine was vital to the nation’s cultural life and economic prosperity.

In previous experiments, Pasteur had discovered that heating the fermented wine would kill the microbes that caused it to spoil. He wasn’t the first to see that connection. Nicolas Appert, the inventor of in-container sterilization, also known as canning, had already shown that treating food with heat could preserve it. Pasteur’s contribution was to determine the exact time and temperature that would kill the harmful microorganisms in the wine without changing its taste. He patented the process and called it pasteurization. Before long, the process was also used for beer and milk.

To alleviate the problem, Pasteur preheated the wine to 50-60 degrees Celsius which killed the unwanted organisms, extended the shelf life of the wine, and ultimately saved the French wine and beer export industry.

Human Tuberculosis is caused by Mycobacterium Bovis that can be found in unpasteurized milk. Source: CDC

The pasteurization of milk didn’t come into practice until the late 1800s. Back then, tuberculosis was commonly carried by milk. A low-temperature, long-time (LTLT) process, also known as batch pasteurization, was first developed to kill the tuberculosis pathogen. The incidence of tuberculosis contracted from milk fell dramatically, and in fact, it no longer makes the Centers for Disease Control and Prevention’s list of food-borne illnesses [source: CDC ].

The first commercial milk pasteurizers were produced in 1882, using a high-temperature, short-time (HTST) process. The first law to require the pasteurization of milk was passed in Chicago in 1908 [source: Sun]. Some people didn’t like the idea of pasteurizing milk in the beginning, for the same reasons that today’s raw milk advocates cite [source: Lewis].

Suitable for Global & New Zealand Pasteurizer Operators:

• Basic Pasteurization Course (1 Day): Cost: $299 USD or $395 NZD + 15% GST
• Advanced Pasteurization Course (2 Days): $526 USD or $695 NZD + 15% GST

For our global clients, course costs are approximated USD and can vary with the exchange rates for New Zealand dollars on the day of booking. Your payment transaction occurs on a globally secure EWAY platform.

While most of us think of milk when we hear the word pasteurization, other foods such as fruit juices, egg products and some alcoholic beverages may be pasteurized. Federal regulations in the United States require dairy products be pasteurized only if they’re to be transported over state lines. The exception to this rule is raw milk cheese that has been aged for 60 days or more. Pasteurization is also required for egg products and most fruit juices [source: Cianci]. Other countries that currently allow the sale of unpasteurized milk include countries in the European Union (except Scotland and Northern Ireland) and Switzerland [source: Cazaux, DBIC].

Batch or vat pasteurization is the simplest and oldest method for pasteurizing milk. A product such as milk is heated to 154.4 degrees Fahrenheit (63 degrees Celsius) in a large container and held at that temperature for 30 minutes. This process can be carried out at home on the stove top using a large pot or, for small-scale dairies, with steam-heated kettles and fancy temperature control equipment. In batch processing, the milk has to be stirred constantly to make sure that each particle of milk is heated [sources: Lewis, Sun, Goff].