Post-pasteurization contamination (PPC) during packaging is the limiting factor affecting the shelf-life of pasteurized refrigerated milk products A flexible film pack aging system, which permitted a high degree of asepsis to be attained, was in vestigated as a means of preventing PPC in a pilot-scale milk processing plant Using this semi-aseptic system, it was possible to prevent PPC to the extent that Gram- negative rods were < 1/100 ml. The shelf-life of semi-aseptically packed pasteurized milk products at 4°C was extended, on average, by about 10 days compared with con ventionally packed pasteurized milk products.
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