The Vegetarian Resource Group Blog

Are Microbial Enzymes Vegan? What About Protease and Pepsin?

Posted on April 27, 2021 by The VRG Blog Editor

By Jeanne Yacoubou, MS

In January 2021, The Vegetarian Resource Group received an inquiry from a food scientist asking if the microbial enzyme protease is vegan. It’s produced by the bacteria Bacillus subtilis on a wheat or soy growth media (fermentation material/substrate).

     Here is our response:

When categorizing any ingredient as vegan, vegetarian, non-vegetarian, or as “typically” one of those three, it is important to consider each ingredient separately. This is especially true when it comes to microbial enzymes.

     You’re right to take the substrate medium into account. Cane sugar is problematic because of the possibility of bone char processing. Whey, L-cysteine, casein, caseinates, or albumen are possibilities as medium components as well.

     Some other components added to media may be problematic, too. (E.g., lecithin from egg or collagen/gelatin from a mammal or fish – although unlikely, it’s a good idea to ask).

     The strictest vegans would ask about animal-derived genetic material. Has any been engineered into the microbial genome to produce the enzyme? Or is the enzyme truly a bacterial protease (as compared to, for example, porcine trypsin produced by bacteria through genetic modification)?

     Lastly, verifying that separation and purification of the protease from the bacterial cells and medium occurred solely by non-animal-derived chemicals and/or mechanical means is needed.”

Are animal-derived enzymes like the protease, pepsin, used in food today?

VRG readers may be interested to know that there are several companies designing microbes to make proteases that have typically been sourced from animals like pigs and cows. The microbes have been genetically engineered to produce enzymes and other proteins used in foods, beverages, and dietary supplements.

     On a commercial basis, animal-derived enzymes are not commonly used today, but they are approved for food use by the United States Food and Drug Administration (FDA), and, so, could be used. Pepsin, a type of protease, is one of them.

     According to the FDA, “Pepsin is an enzyme preparation obtained from the glandular layer of hog stomach. It is a white to light tan powder, amber paste, or clear amber to brown liquid.”

     Creative Enzymes, an enzyme company, states this information about pepsin on its website:

“Pepsin can be used in the food industry. Pepsin is a component of pancreatic curd that condenses and twists during cheese production. Pepsin can be used to modify soybean protein and gelatin and provide whipping qualities. It can also modify the plant protein used in non-dairy snacks and make pre-cooked cereals into instant hot cereals. Pepsin can also be used to prepare animal and plant protein hydrolysates for seasoning food and beverages. In the leather industry, it is used to remove hair and residual tissue from leather and to recover silver from abandoned photographic film by digesting the gelatin layer in which silver is stored.”

     When pepsin is used to make food and beverages, it serves as a processing aid and, as such, does not have to be labeled. Consumers who want to know if an animal-derived pepsin was used in a food or drink must request this information directly from companies.

     Most manufacturers today wish to avoid animal sources (especially in light of the Covid-19 pandemic), present clean labeling on their packaged foods, and/or manufacture consistently pure, plentiful, and sustainable products. For these reasons, they are turning to microbial enzymes instead of animal enzymes.

     Many of the most common enzymes used today as processing aids or in supplements are called digestive proteases that break down proteins. Pepsin may be used to prepare plant-based protein hydrolysates and bioactive peptides. Both are widespread in packaged food, beverages, and dietary supplements.

     Clara Foods recently introduced to the market a yeast-derived pepsin using microbial fermentation technology. The company is also set to offer a chicken-free egg white and is poised to launch similar products manufactured in the same way this year. According to the company, all of their products have the same texture, taste, or functionality in food and beverages as their animal-derived counterparts.

The contents of this posting and our other publications, including The Vegetarian Journal, are not intended to provide personal medical advice. Medical advice should be obtained from a qualified health professional. We often depend on product and ingredient information from company statements. It is impossible to be 100% sure about a statement, info can change, people have different views, and mistakes can be made. Please use your best judgment about whether a product is suitable for you. To be sure, do further research or confirmation on your own.

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