Autolyzed yeast (AY) is an ingredient that comes from the breakdown of the yeast Saccharomyces cervisiae, also known as Baker’s yeast.
It is a food additive used to improve the flavor and nutritional value of many food and bakery products.1
Because it naturally contains free glutamic acid or monosodium glutamates (MSG), it’s used as an inexpensive substitute for synthetic MSG.
The term ‘autolyzed yeast’ refers to the self digestion of “fresh yeast.” Also, it’s the generation of simpler compounds like peptidesm and soluble amino acids such as glutamic acid/glutamates and other substances.
AY is produced by the destruction of yeast cells and the release of amino acids, salts and carbohydrates. Thre are three main routes for producing AY:
Commercially, this yeast is produced using autolysis by the yeast’s own enzymes.2
Heating baker’s yeast cells destroys their cell walls. This releases the proteolytic enzymes present in the yeast. As a result, the cell proteins and production of peptides and amino acids breakdown.
The resulting liquid product is centrifuged and filtered to separate the yeast extract from amino acids. The filtered liquid can be used directly. Or, further spray-dried and/or granulated.
Similar to MSG, AY is used in processed foods such as soups, meats, and vegetarian “meats.” It provides a unique meaty taste or enhances other flavors or tastes, mainly salt.
The high protein content and B-vitamins make AY a highly nutritional product.
The uniqueness of AY lies in its versatility as a flavoring substance and an enhancer of existing tastes. Its applications are prevalent in many food systems. It’s used in baked goods, ranging from spreads and toppings to crackers, cakes, cookies, breads, flat breads, and biscuits.
The high nutritional value of AY makes it a component of some dietary supplements preparations, animal feed and fermentation processes.
Food products containing autolyzed yeast cannot use MSG-free claim. Its usage as a food additive is regulated by FDA (21CFR102.2).3