Next-generation safe, tasty, and healthy fermented Baltic herring products (Clupea harengus membras)

As food, Baltic herring is an underutilized fish species. In this study, fermentation was applied to produce a new type of tasty and safe Baltic herring product with high nutritional value. Baltic herring fillets were fermented using a sourdough starter B-7, and a yoghurt starter Y482F. A fermentation temperature of 32 °C and 50 °C was used for B-7 and Y482F, respectively. Following periods of 2- and 5-days’ fermentation time the fillets were subjected to 14-days cold storage at 2 °C. The fermented samples were tested for microbiological and chemical safety, lipid oxidation, protein degradation levels, and sensory quality. A moderate level of lipid oxidation and low level of protein degradation was observed. Depending on the starters applied, a clear difference in taste and texture between the fermented fish fillets was observed in the sensory evaluation: the products fermented with the B-7 were scored as saltier, fresher, fishier, and sourer than those fermented with Y482F. Although the products’ salt concentration was low (0.4 %), a sufficiently salty taste was still detected. According to the results, the fermentation process developed enables the production of next-generation microbiologically and chemically safe, tasty, low-salt fish food products from an underutilized, vast fish resource.