Current trends and perspectives on the color of fish during low-temperature preservation: A focus on evaluation methods, discoloration mechanism, and protection methods.

The color of fish during low-temperature preservation is one of the most important sensory indicators of their edible quality and shelf-life. This present review provides an in-depth look at color evaluation methods, including sensory, physical, chemical, and new color evaluation techniques. The key factors involved in discoloration of fish are elucidated in terms of major external factors such as temperature, time and processing methods, as well as internal factors such as myoglobin and lipid oxidation, ice crystal growth, and mitochondrial characteristics involved in the three major components of fish (moisture, proteins, and lipids). Meanwhile, the two most widely used methods reviewed in this paper: improved packaging methods and the addition of natural antioxidants and film coatings. This will contribute to provide a theoretical reference for analyzing the formation mechanism of fish color deterioration, and thus propose targeted regulatory strategies for fish during cryopreservation.