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International Panel Confirms Definition of Fermented Foods

Kimchi

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Key Takeaways:

  • A global panel of experts published a consensus statement defining "fermented foods" and foods with probiotics.
  • Fermentation is an excellent way to safely preserve foods, and this method has been used for thousands of years.
  • In the future, food labels should contain accurate information about fermented foods and probiotics so consumers can make informed choices.?

There’s a common myth that fermented foods are the same thing as probiotics, but that’s not the case. Fermenting is a traditional method of food preservation, but only some fermented foods are rich in probiotics.

This differentiation required scientific clarity, which now has been established: A panel of experts recently published?The International Scientific Association for Probiotics and Prebiotics (ISAPP) Consensus Statement on Fermented Foods?in the journal Nature.???

The ISAPP panel consists of 13 researchers, including experts in microbiology, food science, and microbial genetics from across Canada, the U.S., Europe, and Asia.

Noting past inconsistencies in the use of the term "fermented," ISAPP set out to agree upon a definition, describe the role of fermented foods in human health, and look at the safety, risk, and benefits of fermented foods.

Fermented Foods Defined

Foods can be fermented to preserve shelf life, increase food safety, improve functional properties, change taste or texture, and—in the case of wine and beer—create alcohol.?

The agreed-upon definition for fermented foods and beverages is now “foods made through desired microbial growth and enzymatic conversions of food components.”

“There is confusion in the general public and media as to what constitutes a ‘probiotic’ and what constitutes a fermented food, and this confusion extends to the scientific community,” says Michael Gaenzle, MD, a professor at the University of Alberta, member of ISAPP, and co-writer of the consensus statement.

He explained that coming up with concrete definitions is useful for scientific and technical communication, since it’s not always obvious how a certain product should be classified.

Probiotics vs. Fermented Foods

“In my view, there is substantial merit of using microorganisms for fermentation and as probiotics,” says Gaenzle.

He explains that when fermenting food, we use microorganisms to determine and to maintain the quality of foods, while when consuming probiotics, we use microorganisms to maintain or to improve health.

Kathleen Tabb, RDN

I believe the distinction between probiotics and fermented foods is an important one because not all fermented foods have beneficial effects on our microbes.

— Kathleen Tabb, RDN

“The microorganisms that we use for one or the other purpose may be the same, but their use and the criteria for their selection are very different,” says Gaenzle. “This concept can be communicated to consumers and to regulatory agencies only if the terms `fermentation' and `probiotic' are properly defined and communicated.”

For example, yogurt, kefir, miso, tempeh, and unpasteurized kombucha are examples of fermented foods that contain live microorganisms.

But some fermented foods, such as soy sauce, wine, bread, and pasteurized kombucha, do not contain live microorganisms, even though they were produced through fermentation.

The consensus paper differentiates between three types of products:

  1. Probiotics: Live microorganisms that have health benefits, and can be scientifically labeled and sequenced.
  2. Fermented foods: Products made through microbial growth, without requiring evidence for health benefits.
  3. Probiotic fermented foods: products made through fermentation that contain probiotics, and may be labeled with the specific name of the probiotic strain.

It is hoped that these new definitions will influence government regulation on how the food industry should label these foods, and clear up any consumer confusion.

Currently, some fermented foods are not clearly labelled, and may mislead consumers to think they are rich in probiotics when they contain no probiotics at all.?

The ISAPP panel say that “the term ‘probiotic’ should only be used when there is a demonstrated health benefit conferred by well-defined and characterized live microorganisms.”?

Why buy fermented foods?

Fermenting is an excellent way to safely preserve foods and improve shelf life.?? The resulting fermented foods are tasty, so they add pizzazz and variety to the diet.?

“Fermented foods account for a substantial proportion of the total food supply—about 30%—and are thus of economic and scientific importance,” says Gaenzle.

Michael Gaenzle, MD

Fermented foods account for a substantial proportion of the total food supply—about 30%—and are thus of economic and scientific importance.

— Michael Gaenzle, MD

Studies link certain fermented foods to health benefits. For example, studies link yogurt with cardiovascular?health,?? and fermented cabbage, such as kimchi ?? and sauerkraut,?? with gut?health. This may be due to probiotics or some other features of the fermentation process.

The lactic acid bacteria (LAB) used to ferment certain foods has been well-studied?? .

During the fermentation process, LAB synthesize vitamins and minerals, produce enzymes that help digest proteins, and remove some non-nutrients in foods, such as phytates in grains.

Kathleen Tabb, a registered dietitian with Rebecca Bitzer and Associates in Maryland, recommends fermented foods such Greek yogurt, kefir, kimchi, and kombucha to her clients.

“Majority of the time I will recommend fermented foods to my digestive health clients, but I will also recommend them for general health and wellness, as we all need to support our gut microbiome given its impact on many conditions,” says Tabb.?

VeryWell asked Tabb if she thinks the new consensus definitions are an important distinction.?

“I believe the distinction between probiotics and fermented foods is an important one because not all fermented foods have beneficial effects on our microbes,” says Tabb.

“For example, alcohol is made from fermentation, but does not necessarily support our microbial population."

"On the other hand," says Tabb, "Greek yogurt and kefir are fermented foods that DO contain live cultures therefore beneficially affecting one’s health.”

She also says that the distinction should not deter individuals from consuming an array of different foods.

Fermented foods—with or without probiotics—can be a good choice. One red flag to watch out for is the amount of sodium or alcohol in some fermented products.

Otherwise, studies show that fermented foods have a long history of being safe to eat.

What’s Next?

The ISAPP outlines how the consensus statement can positively impact consumers, the food industry, and the government. The hope is that clear definitions will lead to tighter government regulations for food labeling, and more transparent product packaging and marketing from the food industry.

Researchers will continue to study fermented foods and probiotics to identify foods and bacterial strains that are beneficial to human health.

Historically, foods were fermented for preservation, to enhance shelf life, and improve flavor, yet little was known about their health benefits.

The ISAPP panel concludes its consensus statement by saying, “The production of fermented foods and beverages with greater quality control will ensure the delivery of products that provide flavor, texture and health-related attributes.”?

What This Means For You:

Fermented foods have a long history of safe use, but not all fermented foods contain probiotics. There is hope that this consensus statement will influence the food industry to standardize labeling for probiotic-rich fermented foods, and help consumers easily find these products on store shelves.?

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