Yeast Extracts: Production, Properties and Application

Yeast is very well known eukaryotic organism for its remarkable biodiversity and extensive industrial applications. It is one of the most widely used microorganisms in biotechnology with successful applications in the biochemical production. Yeast extract is generally defined as the soluble content of a yeast cell without cell walls.Yeast extract production begins with fresh yeast and consists of 3 steps: fermentation, breaking of the cell wall and separation. Some conventional breaking and disruption methods including mechanical and non-mechanical methods are employed for release of the bioactive compounds. Mechanical methods are applied using bead mill, high pressure homogenizer and ultrasound. In non-mechanical methods electrical, physical, chemical and enzymatic treatments are employed and achieved selective release of these bioactive compounds. Nowadays the most frequently used disruption method in yeast extract production is Autolysis. This method involves attacking the mannoprotein complex and glucan backbone of the yeast cell wall by autolysis or lytic enzymes without destroying the integrity of the cell. The main goal of the current study is the reviewing of the yeast extract, extraction methods especially autolysis. This work also targets application of the yeast extract.

Keywords:

Yeast , Yeast extract , Cell disruption , Autolysis.