[Vitamin B1 and B2 ratio as a method of brewer's and food yeast identification].

The data on vitamins B1 and B2 content in dry brewer's and baker's yeast are submitted. Their significance as these nutrients source is evaluated. Brewer's yeast are mainly the source of vitamin B1 while baker's yeast--the source of vitamin B2. 5 g of yeast give 10 per cent of vitamin B1 and B2 daily recommended allowance correspondingly. Vitamin B1 and B2 ratio has been proposed as a identification criteria of brewer's and baker's yeast. Ratio more than 1.0 gives evidence that this is brewer's yeast. Vitamin B1 content 4 mg per 100 g or more and at the same time vitamin B1 and B2 ratio exceeding 3.0 demonstrate high quality of brewer's yeast.