Working in health food stores for several years, I have heard a lot of confusion amongst customers regarding the differences between the various forms of supplemental and baking yeasts. These include nutritional yeast, brewer’s yeast, and baker’s yeast, popularly referred to as dry active yeast, or instant yeast.
Yeasts, generally speaking, are microorganisms and, like mushrooms, are part of the Fungi kingdom. There are over 2,000 varieties of yeasts, and they exist all over the world, wherever there is plant matter. Yeasts feed on sugars found in grains, fruits and vegetables and produce carbon dioxide and alcohol as a byproduct of consuming this sugar.
Baker’s Yeast (active)
Yeast is responsible for fermentation. It is the yeast species Saccharomyces cerevisiae (S. cerevisiae) that converts carbohydrates to carbon dioxide and alcohol during fermentation. It is this same species, found in baker’s yeast, that converts the sugar in dough into carbon dioxide and ethanol, causing the bread to rise, or leaven. Prior to the 1800’s much of the yeast used in bread making was taken from the production of beer. In the late 1800’s Great Britain introduced specialized growing vats for S. Cerevisiae, and the United States soon followed with a process that concentrated the yeast, and allowed for commercial production.
During World War II, a form of baker’s yeast known as active dry yeast was developed, which did not require refrigeration and baked breads twice as fast as previous yeasts. Today it is very easy to find active dry yeast, or instant yeast for baking in any grocery store.
As mentioned, baker’s yeast is known as an “active” yeast and is not safe for consumption by itself. The yeast will continue to grow and expand within the gastrointestinal system, causing severe distress and nutritional deficiencies. There are two common forms of inactive yeasts, nutritional yeast and brewer’s yeast, that are safe for human consumption, and will not lead to yeast overgrowth or infection.
Nutritional Yeast (inactive)
Nutritional yeast is a flakey yeast that is popular among vegetarians and vegans for its nutrient density. It is also a form of S. cerevisiae, however it has been pasteurized and dried to deactivate it, which also enhances its nutritional properties. It is rich in niacin, folic acid, zinc, selenium, thiamine, and beta glucans for immune support.
Nutritional yeast is a complete protein, providing all nine essential amino acids, and is often fortified with vitamin B12, making it it popular among vegetarians, and vegans. Nutritional yeast has shown anti-viral and anti-bacterial properties and has been used by herbalists to treat infection, acne, low appetite, diarrhea and to stimulate the immune system. This yeast has a rich, nutty flavor and can easily be substituted for cheese in most recipes, as well as used as a topping for toast, vegetables, soups and popcorn. It is commonly grown on sugar beets, which are often genetically engineered. For this reason, it is important to check your labels and research the company in which you are buying from. Additionally, not all companies will fortify the yeast with B12, so if that is your goal, make sure to read the label.
*Michelle has quite a few recipes using nutritional yeast as an ingredient. Here is a “cream sauce” for you to try. Type Nutritional Yeast into the search box on the upper right corner of this page to get all of her recipes that contain it.
Brewer’s Yeast (inactive)
Brewer’s yeast is also a strain of S. cerevisiae that has been pasteurized and deactivated, but it is historically produced as a byproduct of the beer making industry, giving it a different nutrient profile. Brewer’s yeast is also rich in many B vitamins, but does not provide B12 as found in nutritional yeast. This yeast is also used to treat many types of digestive issues including diarrhea, and IBS.
Today, brewer’s yeast is not always produced as a byproduct of beer making, but can also be grown on barley or malt, which mimics the brewery process, but also leaves you with a product that can contain gluten. This also makes the yeast’s nutritional properties different than commonly thought. For example, brewer’s yeast is thought to be a rich source of chromium, which is true, but only when the yeast comes from the beer making process. As with anything, be sure to check your labels and research the company you are purchasing from to ensure you are buying what you intended.
*Post and photo of nutritional yeast by Michelle