Agri-Food Engineering and Biotechnology Department, Technical University of Catalonia (UPC), Esteve Terradas, 8, 08860 Castelldefels, Barcelona, Spain.
Food Sci Technol Int. 2011 Feb;17(1):5-13. doi: 10.1177/1082013210382479. Epub 2011 Feb 7.
Freeze concentration is a process of concentrating liquid products by freezing the water content and subsequently removing the so-formed ice crystals from the food system. In dairy processing, this technology offers the advantage of minimizing the heat abuse of sensitive milk components, such as proteins and flavors. It thus provides an opportunity for producing dairy ingredients with enhanced functional and organoleptic qualities. By freeze concentration, skim milk has been concentrated up to 40 wt% total solids (TS) and whole milk up to 44 wt% TS. Lactose and lipids are more concentrated in the ice fraction than in the concentrated fraction. Proteins (casein and whey protein) decrease the ice growth rate and the high viscosity is a limiting factor for the freeze concentration of both skim milk and whole milk. In this study, the most important studies relating to the suspension, block and layer freeze concentration of milk are summarized, analyzing results and indicating how freeze concentration process efficiency of dairy products can be improved.
冷冻浓缩是一种通过冷冻含水量并随后从食品系统中去除形成的冰晶来浓缩液体产品的过程。在乳制品加工中，该技术的优点是最大限度地减少对敏感乳成分（如蛋白质和风味）的热滥用。因此，它为生产具有增强的功能和感官品质的乳制品成分提供了机会。通过冷冻浓缩，脱脂奶可浓缩至总固体 (TS) 含量 40wt%，全脂奶可浓缩至 TS 含量 44wt%。乳糖和脂肪在冰相中比在浓缩相中更集中。蛋白质（酪蛋白和乳清蛋白）降低了冰的生长速率，高粘度是限制脱脂奶和全脂奶冷冻浓缩的一个因素。在这项研究中，总结了与牛奶悬浮液、块状和层状冷冻浓缩有关的最重要的研究，分析了结果并指出如何提高乳制品冷冻浓缩过程的效率。
