Modeling‐assisted minimal heat processing of Atlantic cod (Gadus morhua)

Abstract

AbstractThis study investigates how product quality and shelf life of vacuum‐packed cod loins are affected when surface bacteria are targeted in thermal processing regimes. A mathematical heat transfer model was used to generate two mild thermal processing regimes for temperature controlled water baths at 70 °C and 90 °C. The results show that shelf life assessment based on sensory evaluation is closely linked to microbial growth. This study shows that even if mild heat treatments do have a noticeable effect of inactivating bacteria on the surface of the fish muscle, such processes do not prolong shelf life considerably. This may be due to the overall limited effect of mild heat processing on bacterial inactivation, but may also be explained by the fact that for postrigor fish, the microbial contamination might be at a too advanced stage for the investigated mild processing to have significant effect.Practical applicationsFor the consumer fresh fish is a superior product compared to frozen fish. Consequently, there is a higher demand and a higher market price for fresh seafood products. The aim of the present study was to evaluate in‐pack surface pasteurization as a mean to increase shelf life for a prepackaged white fish product. Since the surface of the fish fillet is the entry point of microbial contamination as well as the main colonization area, targeting the surface seems the obvious choice to minimize the negative impact of extensive heat processing. We show that modeling the heat treatment is a valuable tool for limiting the detrimental effect of heat treatment. However, when microbial contamination is high, very mild heat processing does not prolong shelf life considerably.