Pasteurized vs. Unpasteurized Foods: What’s the Difference?

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You may have had to decide between pasteurized and unpasteurized food products at some point and wondered which is better to choose.

Pasteurized foods have been exposed to high temperatures to destroy harmful microbes, such as bacteria and viruses, which cause foodborne illnesses (1).

Although pasteurization is a common practice that makes food safer to eat and extends shelf life, not all foods can be pasteurized. Plus, pasteurized foods are still at some risk of contamination from harmful microbes (1, 2).

Some people claim that unpasteurized foods have more nutrients and taste better, but evidence shows these foods are less safe — and nutrient differences may be minimal.

This article covers the difference between pasteurized and unpasteurized foods, the benefits and downsides of each, and how to know which option you should choose.

A person reads a label on a glass bottle of milk at a grocery store.Share on PinterestASphotowed/Getty Images

What does ‘unpasteurized’ mean?

Unpasteurized foods are sold even though they have not been treated with high temperatures. Foods that haven’t been pasteurized include (2):

  • raw milk
  • some artisanal cheeses
  • some unpasteurized versions of juices and meats

Many food safety concerns and a high risk of foodborne illness are associated with eating unpasteurized foods, although there may be a few benefits.

Still, evidence indicates that the health risks appear to outweigh any potential benefits in most cases.

Here are the benefits and downsides of unpasteurized food products.

Benefits of eating unpasteurized foods

Unpasteurized food is more likely to retain its organoleptic properties and may sometimes have greater nutritional value (1). The term “organoleptic properties” refers to the food’s taste, appearance, and smell.

Exposure to high temperatures during pasteurization not only kills harmful bacteria and viruses in foods. It may also negatively affect the nutritional quality, appearance, and flavor of the food (1, 3).

For instance, some research demonstrated that pasteurization reduced the protective antibodies and immune-supportive vitamin C and zinc in donor human milk (3).

However, other research shows that these nutrient losses in human milk are minor and that the benefits of pasteurization are greater than the risks (4, 5).

Downsides of eating unpasteurized foods

Unpasteurized foods are associated with the occurrence of foodborne illnesses from bacteria, such as Brucella, Cryptosporidium, Listeria monocytogenes, and antibiotic-resistant Staphylococcus aureus (6, 7, 8, 9).

In particular, scientific literature frequently mentions that unpasteurized milk and dairy products are particularly high risk foods and common causes of these foodborne illnesses (6, 7, 8, 9).

These bacterial infections may last from days to weeks. Effects range from mild symptoms — like fever, diarrhea, vomiting, muscle aches, abdominal pain, and poor appetite — to severe outcomes like miscarriage and even death (10, 11, 12).

Unpasteurized foods present even greater health risks and are more dangerous to people with compromised immune systems, such as older adults, pregnant people, young children, and those with health conditions like cancer (13).

Summary

Unpasteurized foods are slightly more likely to retain natural tastes, appearances, flavors, and nutrients, but they are strongly associated with foodborne illnesses. Evidence indicates that the risks of consuming unpasteurized foods greatly outweigh the benefits, especially for immune-compromised people.

What does ‘pasteurized’ mean?

Pasteurization is a common food safety practice that exposes some foods to high temperatures for a specific period of time to kill any harmful bacteria and viruses that cause foodborne illnesses (1, 13).

Developed by French chemist Louis Pasteur and his team in 1864, decades of research highlight the benefits that pasteurization offers to human health (13, 14, 15).

Types of pasteurization

Given the especially high risk of foodborne infections from milk and dairy products, you’ve most likely heard of pasteurization in the context of milk. Health authorities also tend to focus on milk when it comes to pasteurization.

According to the Food and Drug Administration (FDA), these are the types and specifications of pasteurization (15, 16):

TypeTemperatureTime VAT63ºC (145ºF)30 minutesHigh temperature, short time (HTST)72ºC (161ºF)15 secondsHigher-heat, shorter-time (HHST) 189ºC (191ºF)1.0 second Higher-heat, shorter-time (HHST) 290ºC (194ºF)0.5 secondsHigher-heat, shorter-time (HHST) 394ºC (201ºF)0.1 secondHigher-heat, shorter-time (HHST) 496ºC (204ºF)0.05 secondsHigher-heat, shorter-time (HHST) 5100ºC (212ºF)0.01 secondUltra pasteurization (UP)138ºC (280ºF)2.0 seconds

If the milk contains sweeteners or has a fat content of 10% or more, the pasteurization temperatures are increased by an additional 3ºC (5ºF) (15).

Eggnog has its own specifications for VAT, HTST, and HHST pasteurization (15, 16).

Benefits of eating pasteurized foods

Pasteurization is an effective method of improving the safety and quality of foods, especially milk and dairy products. Medical and scientific communities have demonstrated the efficacy and safety of pasteurization over time (1, 14).

In fact, pasteurization of donor human milk has even been shown to inactivate SARS-CoV-2, the virus that causes COVID-19, in the milk (5).

Pasteurization is proven to reduce health risks in humans, especially those who are immunocompromised.

Downsides of eating pasteurized foods

Unfortunately, not all foods can be pasteurized, and pasteurized foods can still become contaminated with harmful microbes if they are not stored, handled, or prepared properly.

Plus, food manufacturers aren’t required by law to label foods as pasteurized or unpasteurized, which can make it harder to choose.

Fresh produce, meat, fish, and poultry are not subjected to heat pasteurization even though they are high risk foods for foodborne infections. And even pasteurized foods may later become contaminated during preparation and storage based on food handling practices.

That’s why it’s important to follow food hygiene and safe food handling guidelines set by the FDA, whether you know the food you’ve bought is pasteurized or not (17).

The high temperatures required for purization may alter the appearance, taste, flavor, and nutritional profile of some foods, although these changes are generally minor (3, 4, 5).

Summary

Pasteurization is shown to reduce human health risks like foodborne illnesses, but pasteurized foods may still become contaminated if they aren’t stored or prepared following safe food handling practices. Follow the FDA food safety recommendations, even with pasteurized foods.

Commonly pasteurized foods

Pasteurized foods can often be identified by their food package label, though there are often unpasteurized versions as well — for instance, milk and kombucha are sold in both forms (18).

Unpasteurized foods may be labeled as “raw” or “natural,” such as in the case of some juices, according to older guidance published by the United States Department of Agriculture (USDA) (19).

Here are some commonly pasteurized foods (19, 20):

  • eggs and egg products
  • juice
  • alcoholic and fermented beverages (beer, wine, cider, kombucha)
  • dairy products (milk, cheese, butter, ice cream, yogurt, cream)
  • frozen desserts
  • imitation meats and deli meat
  • nuts (almonds, peanuts)
  • flour and its products (bread, cereal, etc.)

Summary

Some foods are available both as unpasteurized and pasteurized, including juices, dairy products, alcoholic beverages, kombucha, imitation meals, nuts, and flour-based products.

Which should you choose?

Although unpasteurized foods may have a better flavor profile and slightly more nutrients in some cases, you should choose pasteurized foods when possible.

Pasteurized foods have been shown to be safer, have a longer shelf life, and reduce the risk of foodborne illnesses.

Protection against foodborne illness is especially beneficial for older adults, young children, pregnant people, and people with suppressed immune systems due to underlying health conditions (13).

However, everyone should still be mindful and adhere to the recommended safe food handling guidelines. Remember that pasteurized foods can still become contaminated with harmful microbes during storage and preparation (17).

Summary

Choose pasteurized foods, which are shown to be safer to eat, have a longer shelf life, and reduce the risk of foodborne illnesses. Pasteurization is especially important for older adults, children, pregnant people, and those with suppressed immune systems. Practice safe food handling, even with pasteurized foods.

The bottom line

Unpasteurized foods are sold in their raw forms without having been exposed to high temperatures, which kills harmful microbes. They are associated with an increased risk of foodborne infections.

Pasteurized foods are heat-treated and safer for consumption, especially for those with suppressed immune systems, including older adults, young children, and pregnant people.

Commonly pasteurized foods include juices, dairy products, alcoholic beverages, kombucha, imitation meats, nuts, and flour-based products like bread and cereal.

Just one thing

Try this today: During your next grocery haul, look for the word “pasteurized” on food packages of commonly pasteurized foods or read the ingredient list on the nutrition labels to choose safer-to-eat options.