Raw materials of cooked ring sausages as a source of spoilage lactic acid bacteria

Abstract

The microbial numbers and the lactic acid bacteria population of the raw materials of cooked ring sausages were studied in order to determine the presence of the spoilage lactic acid bacteria of the sausages. The highest aerobic plate counts and lactic acid bacteria counts (up to the level of 108 and 105 CFU/g, respectively) were found in the pork skin emulsion and the meat trimmings. Lactic acid bacteria were also commonly found in the skim milk powder and the potato flour. Lactic acid bacteria isolates able to multiply at 8°C were recovered from all the raw materials studied except for the commercial spice mixture. These isolates could be divided into 11 different groups according to their morphological and biochemical characteristics. Isolates resembling the lactic acid bacteria strains responsible for the spoilage of vacuum-packed cooked ring sausages were found in the pork skin emulsion, the meat trimmings, and the potato flour. These raw materials can thus form a source for the spoilage bacteria of the sausages at a sausage processing plant.