We’ve seen a lot of conversation and confusion around pasteurization and how it’s used in a food safety setting. In this blog post, we take a look at pasteurization.
Top takeaways:
- Pasteurization is a heat treatment that ensures food and beverage safety by destroying harmful microorganisms.
- Pasteurization is a chemical-free process that ensures safety without adding additional ingredients.
- Pasteurization reduces foodborne illness risks, extends shelf life, and helps reduce food waste.
What is pasteurization?
Pasteurization is the term used to describe a heat treatment process designed to kill or deactivate harmful pathogens and microorganisms that may be present in foods or beverages without significantly impacting their taste, texture, or nutritional value.
What does pasteurization do? Why do we pasteurize foods and beverages?
Food safety is the primary reason food and beverage producers pasteurize products. It reduces and frequently eliminates harmful pathogens and microorganisms, which greatly reduces–typically eliminating–foodborne illness outbreaks, keeping us healthy and safe.
Additionally, pasteurization helps extend the shelf-life of the food or beverage by eliminating microorganisms that accelerate the rate of spoiling. So, it decreases unnecessary food waste, while maintaining its core beneficial properties.
How does pasteurization work?
Pasteurization is a process that involves three key steps:
- Heating: The manufacturer heats the food or beverage to a specific temperature.
- Holding: The manufacturer keeps the product at the required temperature for a set time.
- Cooling: The manufacturer quickly cools the product to prevent it from impacting the product and prevent contamination.
There are several methods and requirements available to people for pasteurizing products. The selected method is selected based on the food or beverage and the requirements needed to ensure its effectiveness:
- High-Temperature Short Time (HTST): Common for milk and juices, this involves heating to about 161°F (72°C) for 15 seconds.
- Ultra-High Temperature (UHT): Used for shelf-stable products like milk and cream, this heats the product to around 275°F (135°C) for 2-5 seconds.
- Low-Temperature Long Time (LTLT): This method heats the product to about 145°F (63°C) for 30 minutes and is often used for smaller-scale productions.
How does pasteurization destroy harmful microorganisms but not beneficial microorganisms?
Many harmful microorganisms (e.g., Salmonella, E. coli, etc) are more heat-sensitive compared to many harmless or beneficial microorganisms because pathogens often have fragile cellular or capsid structures, making them more susceptible to heat damage.
Some beneficial microorganisms, such as probiotics in certain dairy products, have higher heat tolerance, so they remain in the product.
Does pasteurization sterilize the food or beverage?
No, pasteurization is not designed to sterilize food or beverages. Products that have undergone pasteurization will still contain both harmless and beneficial microorganisms.
Does pasteurization add chemical ingredients or additives to foods and beverages?
Pasteurization does not add chemical ingredients or additive ingredients to foods and beverages. It only applies heat.
When using pasteurization processes, we reduce or eliminate the need for chemical preservative ingredients.
What kinds of foods and beverages benefit from pasteurization?
Pasteurization helps keep a wide variety of products safe for consumers, including:
- Dairy: Milk, cream, cheese, yogurt, and ice cream are pasteurized to eliminate pathogens commonly found in raw milk.
- Beverages: Fruit juices, soft drinks, and alcoholic beverages like beer and wine.
- Egg Products: Liquid eggs and egg-based products to reduce the risk of Salmonella contamination.
- Sauces and Condiments: Ketchup, mayonnaise, and salad dressings are often pasteurized for safety and shelf stability.
- Packaged Foods: Soups, canned vegetables, and ready-to-eat meals.
Does pasteurization change the nutrient profile of foods and beverages?
Pasteurization does not dramatically change the nutrient profile of foods and drinks. We know some minor changes in vitamin content have been observed with some foods and beverages. Still, the changes are not significant enough to outweigh the benefit of dramatically reducing foodborne illness.
Is it safe to consume unpasteurized foods and beverages?
Consuming high-risk, unpasteurized foods and beverages can pose a significant safety risk that can lead to severe, adverse health outcomes.
High-risk foods and beverages include, but are not limited to:
- Raw milk
- Raw eggs
- Raw juices
Consuming these raw foods can significantly increase the risk of contracting a foodborne illness from a pathogen, including but not limited to:
- Salmonella
- Listeria monocytogenes
- Escherichia coli (E. coli)
- Campylobacter
- Mycobacterium bovis
The populations most vulnerable to severe adverse outcomes include
- Pregnant people
- Infants and children
- Elderly people
- People with compromised immune systems.
It’s not advisable to consume high-risk, raw, unpasteurized food and beverages.
The good news.
Pasteurization is a simple, chemical-free way to make food and drinks safer by destroying and greatly reducing harmful germs. It keeps the taste, texture, and nutrients intact, extends shelf life, and cuts down on food waste—all with just heat, no additives so you can safely enjoy milk, juices, and many other foods and beverages.
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Learn more: citations and further readings.
Inanoglu, S., Barbosa-Cánovas, G. V., Sablani, S. S., Zhu, M.-J., Keener, L., & Tang, J. (2022). High-pressure pasteurization of low-acid chilled ready-to-eat food. Comprehensive Reviews in Food Science and Food Safety. https://doi.org/10.1111/1541-4337.1305
Silva, F. V. M., Gibbs, P. A., Nuñez, H., Almonacid, S., & Simpson, R. (2014). Thermal processes | pasteurization. C. A. Batt & M. L. Tortorello (Eds.), Encyclopedia of food microbiology (2nd ed., pp. 577–595). Academic Press. https://doi.org/10.1016/B978-0-12-384730-0.00404-3
Wayne, M. T. (2021). Editorial on pasteurization. Advances in Dairy Research, 9(1), 1. https://www.imedpub.com/articles-pdfs/advances-in-dairy-research-pasteurization.pdf
U.S. Food and Drug Administration. The dangers of raw milk: Unpasteurized milk can pose a serious health risk. U.S. Food and Drug Administration. Retrieved November 18, 2024, from https://www.fda.gov/food/buy-store-serve-safe-food/dangers-raw-milk-unpasteurized-milk-can-pose-serious-health-risk
U.S. Food and Drug Administration. (n.d.). What you need to know about juice safety. Retrieved November 18, 2024, from https://www.fda.gov/food/buy-store-serve-safe-food/what-you-need-know-about-juice-safety
U.S. Department of Agriculture, Food Safety and Inspection Service. (n.d.). Egg products and food safety. Retrieved November 18, 2024, from https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/eggs/egg-products-and-food-safety
Historical context: Wilson, G. (1938). Pasteurization of milk. Nature, 141(3577), 579–581. https://doi.org/10.1038/141579a0