The Effect of Bovine Colostrum on the Lactic Flora of Yogurt and Kefir - Abstract
The objective of this study was to determine the effect of colostrum on microbial populations of yogurt and kefir. For this purpose, raw bovine colostrum is freeze-dried and added to yogurt and kefir on 8% and 16% (w/w; colostrum/product) dilutions. The results showed that, effect of colostrum on total mesophilic aerobic bacteria counts of yogurt and kefir are negligible. Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus counts were 0.26-0.29 log CFU/g and 0.38-0.67 log CFU/g higher in colostrum added yogurt samples, respectively. In kefir, lactic streptococci and lactobacilli counts were higher than that of yogurt. However, they weren’t affected from colostrum addition, statistically. This study showed that, colostrum, which contains antimicrobial substances (immunoglobulins, lactoferrin, lactoperoxidase, lysozyme and cytokines), don’t have an adverse effect on specific microbial floras of fermented dairy products such as yogurt and kefir. As a result, colostrum can be added to yogurt and kefir to increase their functional properties.