Northeast Dairy Foods Research Center, Department of Food Science, Cornell University, Ithaca, NY 14853.
Northeast Dairy Foods Research Center, Department of Food Science, Cornell University, Ithaca, NY 14853.
J Dairy Sci. 2021 Jul;104(7):8314-8325. doi: 10.3168/jds.2020-18706. Epub 2021 Apr 2.
Lactose has different uses in the dairy, food, and pharmaceutical industries. Being aware of the different forms of lactose and their concentrations can be very helpful in managing dairy product quality, properties, and manufacturing efficiency. Correct measurement and reporting of lactose concentration in milk and other dairy products will be of increased importance in the future as more value-added uses of lactose are developed and as milk lactose data are used in farm management decision making. Lactose should be reported as anhydrous lactose because lactose data will be used to make increasingly important decisions in dairy processing, dairy product labeling, and milk production in the future. Lactose also plays an important role in milk synthesis within a cow. Milk production factors and dairy cattle breed selection influence the amount of high value fat and protein produced per unit of lactose. If the off-farm value of lactose remains low, more attention may be focused on using ultrafiltration to process milk and leave 50 to 60% of the lactose and water from milk at the farm to recover the energy value of the lactose as feed and reduce the hauling cost of the high value components of milk to a dairy product manufacturing factory. Many methods exist to determine lactose concentration, but the most important methods are enzymatic assays, HPLC, and mid-infrared analysis. New, value-added uses for lactose need to be developed. Consistent and accurate methods of lactose measurement and consistent expression of lactose results will support this development process. Starting in January 2017, the USDA Federal Milk Market Laboratories began reporting lactose content of milk as anhydrous lactose and discontinued the reporting of lactose by difference.
乳糖在乳制品、食品和制药行业有多种用途。了解乳糖的不同形式及其浓度对于管理乳制品质量、特性和生产效率非常有帮助。随着乳糖附加值用途的不断开发，以及牛奶乳糖数据在农场管理决策中的应用，未来对牛奶和其他乳制品中乳糖浓度的正确测量和报告将变得更加重要。乳糖应报告为无水乳糖，因为未来乳糖数据将用于在乳制品加工、乳制品标签和牛奶生产中做出越来越重要的决策。乳糖在奶牛体内的牛奶合成中也起着重要作用。牛奶生产因素和奶牛品种选择会影响每单位乳糖产生的高价值脂肪和蛋白质的数量。如果乳糖的场外价值仍然较低，人们可能会更加关注使用超滤来处理牛奶，并将 50%至 60%的乳糖和水留在农场，以回收乳糖的能量价值作为饲料，并减少高价值牛奶成分运往乳制品制造工厂的运输成本。有许多方法可以测定乳糖浓度，但最重要的方法是酶法测定、高效液相色谱法和中红外分析。需要开发新的、有附加值的乳糖用途。一致和准确的乳糖测量方法以及一致的乳糖结果表达方式将支持这一开发过程。从 2017 年 1 月开始，美国农业部联邦牛奶市场实验室开始报告牛奶中的乳糖含量为无水乳糖，并停止报告乳糖差值。
