Foods and Nutritional supplements

Marmite and Vegemite, products made from yeast extract

Marmite and Vegemite are dark in colour

Yeast is used as an ingredient in foods for its umami flavor, in much of the same way that monosodium glutamate (MSG) is used and, like MSG, often contain free glutamic acid. Examples include:

• Yeast extract, made from the intracellular contents of yeast and used as food additives or flavours. The general method for making yeast extract for food products such as Vegemite and Marmite on a commercial scale is heat autolysis, i.e. to add salt to a suspension of yeast, making the solution hypertonic, which leads to the cells’ shrivelling up. This triggers autolysis, wherein the yeast’s digestive enzymes break their own proteins down into simpler compounds, a process of self-destruction. The dying yeast cells are then heated to complete their breakdown, after which the husks (yeast with thick cell walls that would give poor texture) are removed. Yeast autolysates are used in Vegemite and Promite (Australia); Marmite (the United Kingdom); the unrelated Marmite (New Zealand); Vitam-R (Germany); and Cenovis (Switzerland).
• Nutritional yeast flakes are yellow in colourNutritional yeast, which is whole dried, deactivated yeast cells, usually S. cerevisiae. Usually in the form of yellow flake or powder, its nutty and umami flavor makes it a vegan substitute for cheese powder. Another popular use is as a topping for popcorn. It can also be used in mashed and fried potatoes, as well as in scrambled eggs. It comes in the form of flakes, or as a yellow powder similar in texture to cornmeal. In Australia, it is sometimes sold as “savoury yeast flakes”. # ISO certification in India

Both types of yeast foods above are rich in B-complex vitamins (besides vitamin B₁₂ unless fortified), making them an attractive nutritional supplement to vegans. The same vitamins are also found in some yeast-fermented products mentioned above, such as kvass. Nutritional yeast in particular is naturally low in fat and sodium and a source of protein and vitamins as well as other minerals and cofactors required for growth. Many brands of nutritional yeast and yeast extract spreads, though not all, are fortified with vitamin B₁₂, which is produced separately by bacteria. # ISO certification in India

In 1920, the Fleischmann Yeast Company began to promote yeast cakes in a “Yeast for Health” campaign. They initially emphasized yeast as a source of vitamins, good for skin and digestion. Their later advertising claimed a much broader range of health benefits, and was censured as misleading by the Federal Trade Commission. The fad for yeast cakes lasted until the late 1930s. # ISO certification in India

Probiotics

Some probiotic supplements use the yeast S. boulardii to maintain and restore the natural flora in the gastrointestinal tract. S. boulardii has been shown to reduce the symptoms of acute diarrhea, reduce the chance of infection by Clostridium difficile (often identified simply as C. difficile or C. diff), reduce bowel movements in diarrhea-predominant IBS patients, and reduce the incidence of antibiotic-, traveler’s-, and HIV/AIDS-associated diarrheas. # ISO certification in India

Aquarium hobby

Yeast is often used by aquarium hobbyists to generate carbon dioxide (CO₂) to nourish plants in planted aquaria. CO₂ levels from yeast are more difficult to regulate than those from pressurized CO₂ systems. However, the low cost of yeast makes it a widely used alternative. # ISO certification in India