The Reduction of Aerobic Bacterial Counts of Bovine Milk as Influenced by Heat-treatments at Pasteurisation Temperatures

Abstract

A number of experiments were conducted to evaluate the bacterial reduction of milk as influenced by the heat treatments at pasteurisation temperature (72 °C for 15 s) considering the Indonesian Standard for raw milk values. The milk samples were collected from dairy farmers in Semarang, Salatiga and Boyolali, Central Java, Indonesia. The heat treatments were conducted in 45 mL glasses bottles dipped in water bath. Considering the temperature histories of the experiments and the bacterial counts, nine of twenty samples indicated their reductions were less than 2 logs cycle standardised although the initial numbers were surprisingly less than 1·10 6 cfu·mL -1 .