Food products are very sensitive to environmental conditions. That is especially high in a case of Baker`s yeast. Compressed (fresh) Baker`s yeast is actually microorganism`s strain Saccharomyces cerevisiae. It is unstable at temperatures above 4oC. The reason is budding of cells. If that is the case, yeast cells use stored components for feed. After the complete usage of energy components, cells make autolysis. Autolysis is a process at which cell is going to destroy itself. Cytoplasmic juice goes out of the cell membrane and fills intercellular space. The juice is full with water and components useful for other microorganisms. These conditions make ideal environment for growing other microorganisms and decreasing Baker`s yeast shelf life. The change of water content in the product can change its shelf life. There are food additives able to absorb water. They could be used for protecting the product with water absorbing. Two types of additives (alginates) with high water absorption capacity were observed in use added to compressed yeast. Different concentration of Sodium- and potassium alginates were used in preparation samples of yeast. Based on analysis of few product`s parameters, the samples with 0.2% alginate showed the best results in preservation. Increasing of alginate concentration, increase yeast stability, but decrease water solubility. Using of alginates can increase stability of Baker`s yeast quality