Phosphatase activity levels in pasteurized goats' milk

Abstract

A study of the effect of pasteurization on goats'milk took place in order to compare the effectiveness of two pasteurification processes (low and high pasteurification) by assessing the procedure microbiologically and biochemically. The results revealed that bohA pasteurification processes were effective, showing microbial destruction of approximately 100%. With regard to the determination of phosphatase activity to monitor pasteurification, data in both cases were higher than the limit established for a well pasteurized milk, according to the method used. Machine milked milk showing a lower microbial content nearly achieved the standard level by batch pasteurification, 0.75 μg phenol/ml, but 2.5 μg phenol/ml by the high temperature short time (HTST) method. Phosphatase activity levels of 1.8 and 4.3 μg phenol/ml were the mean values obtained for low and high pasteurification respectively. Our results lead to the conclusion that the batch method for pasteurification of goats' milk is more efficient in terms of total bacterial count than the HTST method. Furthermore, the technique used for the determination of phosphatase activity does not seem to be adequate for pasteurification control of goats' milk, since in very rare situations were we able to attain the limit established