The Use of Color to Determine Fish Freshness: European Seabass (Dicentrarchus labrax)

In this study, the relationship between color and the quality of fish was investigated. Additionally, how the color properties alter as a result of whether the fish is kept in cold water during the storage was also observed. For this purpose, the color changes on both halves of the sea bass (the bottom side dipped in cold water (WS: wet side) and the top side exposed to air (AR: air side)) were analyzed during 4 degrees C storage by computer-based image analysis (CBI). The eyes, gills, and skin of the samples were monitored separately. Along with the color measurements, some freshness parameters, including total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARs), TVC (total viable count), quality index method (QIM), and Torry score sensory analysis were assessed. The results indicated that the shelf life of sea bass was six days. High correlations were obtained between CBI results and the freshness parameters analyzed (min R-2 = 0.844). Among the CBI analyses of skin, gill, and eye segmentation, the best results were achieved via monitoring the skin color. Regardless of the side of the fish (AS or WS) used, our study has revealed that applicable color parameters for the determination of shelf life of sea bass are a* and b*.

Automated summary

The study found that skin color of sea bass was most indicative of freshness during storage at 4 degrees Celsius, with a* and b* being key color parameters for determining shelf life. High correlations were observed between computer-based image analysis (CBI) results and freshness parameters, with a minimum R-2 value of 0.844.