Influence of temperature and time on microbial, physicochemical and functional quality of goat milk

Microbial load in fresh milk has a significant effect on its keeping quality and nutritional value. From Prehistoric time, human used heat process to reduce microbials load in raw milk to improve its sensory characteristics. This research is proposed to treat fresh goat milk with heating process to provide optimal pasteurization conditions that does not  influence the goat milk chemical composition to suite production of goat yogurt powder. The pasteurization conditions considered were: Temperature (72, 80, and 85°C) and time (5, 10 and 15s). These results showed there were a significant difference (P<0.05) between treated milk and Indonesia national standards on viscosity and pH; whereas there was no significant differences on density and titratable acidity. The study results concluded that the temperature and time during heat processing had a significant effect on nutritional compounds of goat milk, with increase in lactose and non-fat solids contents; therefore, treated goat milk at 85°C to 5 s is better than other treatments.   Key words: Goat’s milk, pasteurization, physicochemical analysis, microbiology.