Freezing Effect as a Post-Harvest Storage Technique: Quality of Buffalo Milk

The current study evaluates the effect of freezing types at −20 ± 1 °C on the density, freezing point, specific gravity, fat, protein, and lactose of buffalo milk. Buffalo milk samples were collected and pooled separately in the morning. Milk samples were transferred immediately to the Dairy Chemistry and Technology Laboratory. Organoleptic tests were done to observe flavour and odour, sediment, and texture. Physico-chemical and milk compositions were analyzed by using an automatic ultrasonic milk analyzer calibrated for buffalo milk. In the case of organoleptic assessment, a slightly flat flavour was observed at 168 h of freezing in the single-stage but in the case of multi-stage of freezing, the slightly flat flavour had been observed at 120 h. The physicochemical parameters such as the density, freezing point, specific gravity and the compositions of fat, protein and lactose content of the milk samples were significantly different (p < 0.05) for both single and multi-stage freezing types. It was noted that the milk’s fat, protein, and lactose levels decreased as freezing times increased for both freezing procedures. In conclusion, the milk samples were frozen at −20 ± 1 °C significantly decreased fat, protein, and lactose content. Samples were frozen, thawed, and then refrozen (multi-stage freezing), the loss of components was noticeably greater than when the samples were frozen once (single freezing).