Food safety and microbiological quality aspects of QDS process® and high pressure treatment of fermented fish sausages

A new fermented fish sausage product, based on monkfish, was developed by using an accelerated drying process, the QDS process®. To evaluate food safety, a challenge test was performed, in which the raw materials were inoculated with low levels of Listeria monocytogenes and Salmonella enterica (≤150 CFU/g). The product was manufactured, fermented, QDS dried, and half of the samples were pressurized (600 MPa, 5 min, 13 °C). Pathogens, technological microbiota, spoilage indicator bacteria from fish (hydrogen sulphite producing bacteria, coliforms and Escherichia coli) and physicochemical parameters were monitored during manufacturing and after 6, 13, 20 and 27 days of refrigerated storage at 4 and 8 °C. Results showed that in the finished product, pathogens and spoilage indicator bacteria could not grow but decreased and E. coli was not detected during storage. Pressurization had an important reducing effect on technological microbiota, and eliminated L. monocytogenes, S. enterica, hydrogen sulphite producing bacteria and coliforms immediately after production and during refrigerated storage.