Combination of entropy weighting and global stability index provides a potential strategy for monitoring the shelf-life of Litopenaeus vannamei during cold storage

Monitoring the quality degradation of shrimp during cold storage is a tough task due to the involvement of multi-biological process and the accurate kinetic model is extremely necessary to optimize the storage management. Here, the entropy weighting and global stability index (GSI) were combined to establish the model monitoring the shelf-life of Litopenaeus vannamei during storage at –23, –5, 0, 4 and 9 °C, respectively. The typically quality-related indicators including sensorial score, total aerobic count, total volatile base nitrogen, and activity of protease and polyphenol oxidase was selected to reflect the quality degradation. After systematical calculation, the weighting factors of these indicators were determined, respectively. Subsequently, the zero-order reaction model reflecting the overall quality degradation process was satisfactorily described based on GSI, in which the activation energy (E_a) and reaction rate constant (k₀) were calculated to be (64.78 ± 0.75) kJ/mol and (3.47 ± 0.54) × 10¹¹, respectively. As a consequence, the GSI model was established as following: GSI = 1 – 3.47 × 10¹¹t × exp (–64.78 × 10³/RT), with the relative error of less than 15%. Therefore, the established GSI model could be applied to monitor the quality deterioration of L. vannamei during cold storage and is helpful for distributors and consumers to determine the storing time.