H. ROHM, F. ELISKASES-LECHNER AND M. BRÄUER. 1992. The biochemical properties of 1013 yeasts isolated from various milk products (yoghurt, kefir and cheese environment) were compared. The differences in percentage positive reactions described as variable in the standard descriptions indicate environmental selection mechanisms and the existence of yeast-product associations. The effects of the results on three simplified identification methods are discussed.