The yeast extract powder is made from fresh beer or bread yeast by autolysate of modern biotechnology or enzymatic hydrolysis, which is a powder to be formed by separation, refinement and concentrated spray drying. And it is a mixture of amino acids, peptides, water-soluble vitamins and sugars (mainly mean oligosaccharides and trehalose). It is widely used in the fermentation industry of new biomedicine, amino acid, vitamin, organic acid, enzyme preparation, probiotic fermentation, biological preservative, biological pesticide, microecologics, etc. Total nitrogen (on DM) % 8.0%, Amino nitrogen (on DM) % 3.5%, Ash (on DM) % 15.0%, Moisture % 6.0%