Are Microbial Enzymes Vegan? What About Protease and Pepsin?

By Jeanne Yacoubou, MS

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:

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

     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.”

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

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.

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.”

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

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
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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