Studies on characteristics of Jersey's milk and development of distinctive products

     The raw milk qualities of Jersey and Holstein cows from LRI were compared from 2008 to 2010. The result showed that the components of fat, protein and total solid in Jersey's milk were higher than those in Holstein's milk. The somatic cell count of Jersey's milk in summer season was lower than those in Holstein's milk. The raw milk was centrifuged and divided into cream and low fat milk. The low fat milk was utilized for producing yogurt and kefir within 0~48 hours incubation. The result showed that lactic acid content of the product trended to increase with fermentation time prolong. In yogurt experiment, there was higher than 10 g/L lactic acid productivity when above 24 hours fermentation time. In kefir treatment, there was higher than 10 g/L lactic acid productivity when above 12 hours fermentation time. Both of two kind fermented milk, the kefir incubated for 48 hours had the highest lactic acid productivity about 17.61 g/L. Whey separated from yogurt and kefir for 24~48 hours fermentation. Disk diffusion method was used for investigating the antibacterial activity of yogurt and kefir whey. Result revealed that two kind of whey were active against pathogenic genera Pseudomonas fluorescens. The antibiotic activity of kefir whey was better than the yogurt's. According to the above-mentioned, the reduced fat kefir could be a new bio-material used for skincare products.

(C. Y. Kuo, T. F. Shiao, S. J. Lee and M. L. Wang)