A case of spoilage in wurstel sold in an Italian supermarket

In the current study, the shelf-life and the spoilage of Italian wurstel sold in a local supermarket was investigated. The analysis included identifying the causative microorganisms and the variations in physical-chemical parameters (pH, aW, lactic acid, and ammonia). The spoilage consisted of a white surface coating or slime that appeared after the thirtieth day of storage. The cause of the spoilage was the uncontrolled growth of thermoduric heterofermentative lactic acid bacteria (LAB) that occurred during storage. The LAB, including Leuconostocs and Brochothrix thermosphacta organisms, can survived the pasteurisation process. Due to the deacidifying action of B. thermosphacta and the production of ammonia, there was no evidence of off-odour or off-flavour and no change in pH. Furthermore, no loss of the vacuum seal was observed in the spoiled wurstel.