Properties of Kefir made in Scotland and Poland using Bovine, Caprine and Ovine Milk with Different Starter Cultures

Abstract

Varieties of Kefir were made in Poland and Scotland from bovine, caprine and ovine milk, using Kefir grains and two direct-to-vat inoculation (DVI) starter cultures. The chemical composition (g/kg) of the Kefir ranged from 106-149 for total solids, 29-64 for crude protein, 38-47 for carbohydrate, 7-11 for ash. The fat content was standardized to a mean value of 31 g/kg. Lactic acid bacteria and yeasts were the predominant flora in fresh and stored Kefirs, but some strains decreased by 1 log10cycle during the storage period (12 days). Coliforms were absent (sensitivity=10-1dilution). Microbial metabolites (free fatty acids, diacetyl and ethanol) were associated with species of milk, but the former two components were also affected by storage. The firmness of the product was also influenced by the type of milk used (ovine>bovine>caprine). All the sensory attributes tested were influenced by the type of milk. Storage influenced mouth-feel characters ('serum separation', 'chalky', 'mouth-coating', and 'slimy'). Despite difficulties in comparing results from the Polish and Scottish laboratories, the overall conclusion was similar; the type of milk had greater influence on product characteristics than that of starter cultures. © 2001 Academic Press.