不同类型热处理方式对牛乳品质的影响

Effect of different types of heat treatment on milk quality

目前市场上常见牛奶的杀菌方式有超高温瞬间灭菌(UHT)、巴氏杀菌等,这些牛奶的生产工艺不同,热处理强度不同,活性蛋白的变性率也各不相同。本实验通过比较不同方式热处理对牛奶中α-乳白蛋白、β-乳球蛋白和乳铁蛋白含量的影响,得出蒸汽浸入式直接杀菌(INF)对α-乳白蛋白、β-乳球蛋白和乳铁蛋白的热损伤程度低于UHT灭菌,与巴氏杀菌相当(P>0.5),冷藏条件下,产品的保质期可达21 d,货架期高于巴氏杀菌牛奶。合适、恰当的热处理工艺,不仅可以杀死致病性微生物,同时又能最大限度地保留牛奶中的天然活性蛋白营养,保证牛奶的品质。

At present, the common milk products on the market include pasteurized milk and high-temperature milk. These milk products have different processing techniques, different heat treatment strengths, and different denaturation rates of active proteins. Assessment of the effect of different heat treatment processes on the level of α-lactoalbumin, β-lactoglobulin and lactoferrin was performed. It can be concluded that direct steam infusion process had lower thermal damage to α-lactalbumin, β-lactoglobulin and lactoferrin than UHT(P<0.5), which was equivalent to pasteurization(P>0.5). The shelf life of the product can reach 21 days under refrigeration, that was higher than pasteurized milk. Appropriate and proper heat treatment process can not only kill pathogenic microorganisms to ensure the safety of milk, but also preserve the natural active protein content in milk to ensure the quality of milk.