Effect of Heat Treatments on Physico-chemical properties of Milk Samples

This study assessed the effect of different heat treatments (Low pasteurized at 68°C, Flash pasteurized at 72°C, Boiled at 100°C and Sterilized at 121°C) on the quality of on four types of milk (cow, camel, sheep and goat). Raw milk samples were heated by difference types of heat treatments and physico-chemical characteristics were determined in all samples before and after heating. The results showed significant differences (p≤0.05) between raw milks on density, fat, protein, SNF, moisture content except pH, acidity and lactose content. The results showed that the raw cow milk recorded higher lactose content (4.585%), sheep milk recorded higher acidity (0.156%), density (1.039 g/cm), fat (8.790%), protein (5.750%) and SNF (12.40%), goat milk recorded higher pH (6.9), and moisture (88.60%). The results also showed that heat treatment affected milk properties significantly (p≤ 0.05); increasing heat decreased pH, protein and lactose content. Acidity was highly increased due to heat treatment but SNF, fat, density were stable.