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http://dx.doi.org/10.22424/jmsb.2018.36.1.49

Effects of Heat Treatment on the Nutritional Quality of Milk: V. The Effect of Heat Treatment on Milk Enzymes  

Shin, Hanseob (Division of Animal Science, Chonnam National University)
Oh, Sejong (Division of Animal Science, Chonnam National University)
Publication Information
Journal of Dairy Science and Biotechnology / v.36, no.1, 2018 , pp. 49-71 More about this Journal
Abstract
Heat treatment is the most popular processing technique in the dairy industry. Its main purpose is to destroy the pathogenic and spoilage bacteria in order to ensure that the milk is safe throughout its shelf life. The protease and lipase that are present in raw milk might reduce the quality of milk. Plasmin and protease, which are produced by psychrotrophic bacteria, are recognized as the main causes of the deterioration in milk flavor and taste during storage. The enzymes in raw milk can be inactivated by heat treatment. However, the temperature of inactivation varies according to the type of enzyme. For example, some Pseudomonas spp. produce heat-resistant proteolytic and lipolytic enzymes that may not be fully inactivated by the low temperature and long time (LTLT) treatment. These types of enzymes are inhibited only by the high temperature and short time (HTST) or ultra-high temperature (UHT) treatment of milk.
Keywords
milk enzyme; protease; lipase; psychrotorpic bacteria; UHT;
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