The Science of Yeast


Nutritional Yeast

Visit our Lesaffre Human Care site at to learn more information on our Nutritional Yeast products.

What is Nutritional Yeast?

RED STAR Nutritional Yeast is a primary grown pure culture strain of Saccharomyces cerevisiae.  It is a powdered yeast without leavening power, marketed for its protein and vitamin content. This type of yeast is available in both powder and pill form.

Nutritional Yeast is an excellent source of protein, rich in many of the essential amino acids that complement proteins available from other sources such as corn, wheat, and soy. RED STAR Nutritional Yeast contains an average of 50% protein by weight.

RED STAR Nutritional Yeast is also a rich source of B-complex vitamins that are important for normal and healthy body functions.

How nutritional yeast is made

RED STAR Nutritional Yeast is primary from pure strains of Saccharomyces cerevisiae grown on mixtures of cane and beet molasses. After the fermentation process is completed,”Cream yeast” is heated by means of a heat exchanger and held at pasteurization temperatures for a period long enough to inactivate the yeast. During this holding period, all necessary vitamins are added to meet the requirements of the specific type of nutritional yeast produced.

The yeast is then drum dried before it is ground and shipped to consumers. The drying process assures that all the cells are inactivated in order for the full nutritional benefits to be available.

How Nutritional Yeast is Made

Photo Key:
A) “Seed yeast” is grown in small flasks
B) “Seed yeast” is transferred to 1,000 gallon tanks for fermentation (becomes “stock yeast”).
C) Alcohol from fermentation separated from “stock yeast”
D) “Stock yeast” moved to refrigerated tanks (“Trade Fermenter”) for fermentation cultivation
E) Sterilized molasses, air and nutrients are added to “stock yeast”
F) When yeast is ready to be harvested, fermented yeast liquid is passed through a “Separator” to produce “cream yeast”
G) “Cream yeast” is heated and pasteurized, necessary vitamins are added
H) Vitamin-enhanced “cream yeast” is cooled
I) “Cream yeast” is drum dried
J) The dried yeast is put through a grinder to produce a fine powder
K) Nutritional yeast is packaged and ready for shipping

Visit our Lesaffre Human Care site for more information on our Nutritional Yeast products.