Heat-treatment is one of the most essential steps during the process of bovine colostrum.The effects of the strength of heat treatment on IgG concentration,bacterial count and chemical properties of bovine colostrum were studied,and the pasteurization process was optimized.The experiment results were obtained as follows:The bacterial count decreased below the safety amount when the bovine colostrum was pasteurized at 60 ℃ and 63 ℃ for more than 30 min.IgG concentration decreased with both heating temperature and heating time increased.The Mailard reaction,lipid oxidation and protein hydrolysis were significantly affected by heating temperature.By optimization,the optimum pasteurization process was obtained as heating temperature at 63 ℃ for 30 min,which not only made the bacterial count decrease below the safety amount,but kept the maximum IgG concentration and made the nutrient content lose a little.%热处理是牛初乳加工中必不可少的工艺过程.通过对热处理强度对初乳中IgG保留率、微生物数量以及营养成分损失的影响进行研究,并对巴式杀菌工艺进行优化,得出以下结果:杀菌温度为60℃和63℃,加热时间超过30 min可以将微生物数量降低到安全数量.IgG的保留率随加热温度的升高而降低,随加热时间的延长而降低.加热温度对美拉德反应、脂肪氧化和蛋白质水解反应的影响均显著.通过优化得出,杀菌温度60℃和加热时间30 min,可以既保证微生物安全,同时最大保留IgG的浓度和营养成分损失较低.
展开▼
