tailieunhanh - Ebook Applied dairy microbiology (second edition): Part 2

(BQ) Part 2 book "Applied dairy microbiology" presents the following contents: Fermented milks and cream, probiotics and prebiotics, cheese products, fermented by products, public health concerns, cleaning and sanitizing in milk production and processing, control of microorganisms in dairy processing - dairy product safety systems, regulatory control of milk and dairy products, testing of milk and milk products. | 9 Fermented Milks and Cream Vikram V. Mistry South Dakota State University Brookings South Dakota I. INTRODUCTION Fermented milks result from the selective growth of specific bacteria in milk. These products have evolved around the world over thousands of years and are believed to have originated in the area that is now the Middle East. These products probably resulted from the need to extend the shelf life of milk in the absence of refrigeration Kosikowski and Mistry 1997 . Storage of raw milk at ambient temperature probably led to growth of lactic acid and other bacteria. This bacterial activity produced desirable flavors and importantly increased the shelf life of milk because of a high acid content. Procedures of fermented milk production were subsequently refined the products became popular and gradually spread to Asia Europe and other parts of the world. Consumption is now the highest in European countries but these products form an important component of the diet in many other countries as well Table 1 . Today yogurt buttermilk and sour cream are probably the most widely consumed fermented milk products but there are many different types of such products that are either manufactured commercially or produced on a small scale and sometimes in homes for local consumption. In addition to being excellent sources of nutrients these products have become popular because of potential health benefits which are discussed in Chapter 10. 301 302 Mistry Table 1 World Consumption of Fermented Milks 1998 Country Per capita kg Country Per capita kg Netherlands Czech Republic Finland Portugal 1997 Sweden Hungary Denmark Poland France Slovakia Iceland USA 1997 Germany Australia Israel Argentina Norway Canada Bulgaria Ukraine Austria South Africa Spain China Source International Dairy Federation. 1999. World Dairy Situation. Bulletin No. 339. II. MICROORGANISMS USED TO .