Efficiency of a commercial process for the storage and distribution of vacuum-packaged beef

Abstract

The storage efficiency of a commercial processed for the distribution of vacuum-packaged beef by road was assessed using a temperature function integration technique. Temperature histories were collected from representative samples of product units during the in-plant storage of product before its dispatch and during carriage of product on journeys lasting 2 or more days. The temperature histories were integrated with respect to models relating the growth of psychrotrophic enterobacteria to temperature. The growth of the organisms was considered indicative for the development of spoilage flora. During in-plant storage, the lag induced by vacuum packaging was calculated to be nearly or wholly resolved for the reference bacteria on 31 % of the product units. Assuming the worst case situation of full lag resolution of the bacteria in all product units by the time of loading to transport, proliferations calculated for the periods of transport ranged from 3 to 13 generations. From that data, it was estimated that the product would achieve on average only about 25% of the potential storage life. The major factor contributing to poor storage performance was the failure to equilibrate product to near the optimum storage temperature before the product was loaded to transport.