Storage of Pre-Rigor Fish Muscle at Different Frozen Temperatures: Effects on Water-Holding, Metabolic Process, and Physicochemical Properties of Muscle Proteins

This study examined effects of rigor status (pre- vs post-rigor) and storage temperature (−10 vs −20 °C) on quality of snakehead fish meat. Pre-rigor frozen meat had lower thaw loss and centrifugation loss compared to post-rigor, likely due to a higher pH. Storage temperature did not affect the content of glycogen, lactic acid, and adenosine triphosphate (ATP), but the subsequent degradation of ATP-related compounds was altered in pre-rigor meat. In addition, protein denaturation and proteolysis was generally greater in post-rigor frozen meat. This study demonstrated that the timing of freezing is critical for the quality of frozen fish.