Preservation of Vacuum-Packaged Pork Liver Paté by Fermentation

Fermentation with Lactobacillus plantarum and Pediococcus cerevisiae was evaluated as a natural method of preservation for use in pork liver paté. Addition of both starter strains to a raw meat mix (10⁸ CFU g^-1) lowered the pH to 4.0 in 15 h at 30°C. Subsequent cooking to a core temperature of 70°C followed by vacuum packaging resulted in a product which remained acceptable for longer than 22 days when stored at 4°C and 10°C. Addition of glucose did not increase the activity of the lactic acid starter organisms, indicating the presence of endogenous fermentable substrate in the raw ingredients. Challenge test studies employing Staphylococcus aureus , Salmonella infantis , and Clostridium sporogenes were carried out in finished product at 37°C. No recovery was observed 7 days postinoculation. Results from this investigation indicate the potential use of lactic acid starter cultures to obtain a microbiologically stable product with enhanced safety.