Effects of environmental conditions on microbial proteolysis in a pork myofibril model system

P.M. KENNEALLY, N.G. FRANSEN, H. GRAU, E.E. O'NEILL & E.K. ARENDT.1999.A number of bacterial strains used for meat fermentations were screened for proteolytic activity. A strain of Micrococcus which was found to be proteolytic was evaluated for the effects of environmental conditions on its proteolytic activity against pork myofibrillar proteins using response surface methodology. Three strains of micrococci were also tested for the ability to produce free amino acids from pork myofibrils. Analysis of the effects of environmental conditions showed that proteolytic activity would be minimal under conditions normally found in fermented sausages, thereby suggesting that proteolysis in these products is largely due to endogenous meat enzymes. The three strains of micrococci were shown to produce free amino acids from pork myofibrils, thereby demonstrating the presence of peptidase activity in these strains.