COLD CHAIN INTERRUPTION BY CONSUMERS SIGNIFICANTLY REDUCES SHELF LIFE OF VACUUM-PACKED PORK HAM SLICES

The spoilage of meat products (N>5x10(6) CFU g(-1)) can be delayed by cooling and low-temperature storage and transport. The highest extent of interruption in the cold chain occurs at the time of delivering the meat product to the individual's home after purchasing it. Consumer behaviour and the ambient temperature largely infl uence the shelf life of products. In our research, we examined the buying habits of customers in Hungary. Based on these results, we carried out the cold chain interruption of vacuum-packed sliced ham (1, 2, 3 h) under laboratory conditions, at temperatures of 15, 25, and 35 degrees C. The microbial count was determined by a quick method based on redox-potential measurement in two-three days until the products were deteriorated. Our experiments resulted in the expected outcomes; however, we concluded that even average customer habits (1 h cold chain interruption) at higher temperature periods (T>20 degrees C) decrease the shelf life of ham by 6 days. We set up a mathematical model through which the changes of microbial counts can be determined as a function of product temperature changes, the period of delivery, and the subsequent period of cold storage. R-2= 0.9 correlation was given between predicted and measured microbial counts (logN).