Is Yeast Vegan? The Vegan’s Guide to Yeast

Yeast is not a plant nor an animal. What does that mean for its vegan status?

is yeast vegan in measuring spoon

Treehugger / Joshua Seong

Most vegans consider yeast a vegan-friendly food. Neither animal nor plant, yeast is a microscopic member of the fungus family, and its most common culinary strain is Saccharomyces cerevisiae.

Because yeast is a single-celled organism that metabolizes food into energy, some very strict vegans avoid it on the premise that, by biological definition at least, yeast is alive. But since other fungi are generally accepted as part of a vegan diet, the majority of vegans see no conflict with eating yeast.

Here, we break down the many different types of yeast and explain their roles in veganism.

Why Most Vegans Agree Yeast Is Vegan

Yeast hails from the fungi kingdom. This single-celled, microscopic relative of mushrooms grows naturally on plants and in soil. Since food from the fungus family is permissible in a vegan diet, yeast is generally considered vegan. 

For over 5,000 years, humans have enjoyed Saccharomyces cerevisiae, a strain of yeast responsible for the leavening process in bread and the fermentation in beer and wine. In its active form, S. cerevisiae converts carbohydrates to carbon dioxide, pumping the air into baked goods and providing flavor in alcohol fermentation. If heated, S. cerevisiae is inactivated or “killed” and loses its powers of fermentation. What remains is its savory taste.

In addition to its deep umami flavor, yeast provides a vegan-friendly source of amino acids, proteins, bioavailable minerals, as well as B12 and folic acid (B9). These essential nutrients can be challenging to obtain through an entirely plant-based diet.

Is Yeast Alive?

Technically speaking, yes—yeast is a living unicellular organism. In the same way that humans eat carbs and exhale CO2, yeast “eats” sugar and produces gas. Humans harness the power of yeast’s metabolism to rise bread and ferment alcohol.  Yeast’s ability to metabolize in this way confirms its status as a  “living” organism. 

Unlike members of the animal kingdom, yeast has just one cell and contains no nervous system. Yeast does not suffer in the way multi-cellular animals with nervous systems can suffer. Consequently, mainstream vegans do not see the harvesting or consuming of yeast as animal slavery, exploitation, or cruelty. However, some very strict vegans avoid yeast because it is alive in a fundamental biological sense.

Did You Know?

The relationship between spent yeast from the beer-making process and the manufacture of Marmite is a sustainability success story. Each year Molson Coors, a multinational beer brewing company, produces 11,000 tons of spent yeast during the fermentation process. That yeast is then processed and packaged as Marmite, providing a salient example of turning food waste into a food resource.

Types of Baker’s Yeast

Close up of a glass jar of sourdough starter left to rise on a ledge.
Sourdough starters are an example of wild yeast.

Beachmite Photography / Getty Images

Generally speaking, baker’s yeast is any yeast used as one of the leavening agents in bread products. These live, active forms of S. cerevisiae also give bread its distinct flavor profile. When baked, the heat kills the yeast, ending the fermentation process and making it safe for consumption in more significant quantities. Vegan butter, anyone?

Active Dry Yeast

If you’ve ever made bread at home, you’ve likely encountered active dry yeast. This granulated, dehydrated form of baker’s yeast comes in individual packets or glass jars in the baking aisle at grocery stores. If kept at room temperature, active dry yeast has a long shelf life and remains inactive until introduced to warm water.

Fresh Yeast

Also called cake yeast or compressed yeast, fresh yeast comes in highly perishable blocks of moist, living yeast. When stored in an airtight container, fresh yeast can last two to eight weeks in the refrigerator. Find fresh yeast in the refrigerated section of grocery stores.

Instant Yeast

This fast-acting form of dry yeast has a smaller grain size than active dry yeast. Instant or rapid rise yeast is dehydrated at a lower temperature, allowing most of the yeast to remain alive. That’s why it works best when mixed into dry ingredients, helping bypass the first rise of the bread. Grocery stores carry instant yeast in the baking aisle.

Wild Yeast

A catch-all term for several strains, including Saccharomyces exiguus and Candida milleri, wild yeast can be cultivated with as little as flour and water. Alive and active, wild yeast will continue to metabolize if properly refrigerated and fed. Although wild yeast and sourdough starter are both types of wild yeast, they differ in how they are maintained and their taste; wild yeast has a much milder flavor. Many wines also rely on wild yeast from the grapes as part of the fermentation process.

Types of Brewer’s Yeast

Beer fermenting in a huge stainless steel container in a brewery.
Beers that have a thick head of foam are generally made with top-fermenting ale yeast.

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Like baker’s yeast, brewer’s yeast is a live culture of S. cerevisiae available in both powder and liquid form. The yeast is deactivated during the beer brewing process and is therefore rendered safe to consume in larger quantities. Cheers to that!

Lager Yeast (Bottom-Fermenting) 

Slower fermentation defines this cooler temperature yeast. It can take weeks for bottom-fermenting yeast to bloom, elongating the brewing time but providing the distinct “clean” flavor of lagers and pilsners. 

Ale Yeast (Top-Fermenting)

It’s easy to identify top-fermenting yeast—early in the fermentation process, this fast-acting yeast creates a thick head (i.e., foam) on top of the liquid. Warm temperatures ferment ales, porters, stouts, and wheat beers in just a few days.  

Types of Cooking Yeast

Raw, yellow organic granulated nutritional yeast flakes in a bowl
Nutritional yeast makes a great vegan cheese substitute.

bhofack2 / Getty Images

Unlike baking yeasts that provide leavening power, cooking yeasts offer flavor. Granular nutritional yeast and yeast extract both come from S. cerevisiae, which is generally grown on molasses. Once harvested, the yeast is washed and dried, killing (inactivating) the yeast and making it safe for consumption in large amounts. Bring on the vegan nachos!

Yeast Extract

Best known in its brown paste form, yeast extract is the main ingredient in Vegemite and Marmite, popular brands of savory food spread in Australia, New Zealand, and the U.K. Yeast extract comes from the contents of the yeast cell without the cell wall. As a food additive, yeast extract provides umami, one of the five basic tastes. Many processed foods, including vegan products intended to have a “meaty” flavor, include yeast extract to provide this savoriness.

Nutritional Yeast

Lovingly and derisively known as "nooch" in health food circles, nutritional yeast is an inactive form of S. cerevisiae and a popular cheese substitute in many vegan recipes. You can find these yellow, granular flakes in bulk at health food stores. As veganism continues to rise in popularity, more and more mainstream grocery stores, too, carry nutritional yeast. 

Torula Yeast

Torula yeast comes from a different strain entirely—Candida utilis. A by-product of the paper processing industry, torula yeast naturally grows on liquidized wood pulp. The yeast is collected, dried (inactivating it), and ground into a powder. Because of its smoky, rich flavor, torula yeast often appears in vegan meat and cheese substitutes. 

Frequently Asked Questions
  • Can vegans eat yeast?

    Yes, the majority of vegans consider yeast to be a vegan-friendly food. Unlike members of the animal kingdom, yeast has just one cell and contains no nervous system, therefore it is not cruel to consume.

  • Does yeast have dairy?

    No, yeast is dairy-free. While certain breads can contain dairy, yeast itself never does.

  • Why do vegans not eat yeast?

    Some very strict vegans avoid yeast because it is a living single-celled organism.