Effect of oxidation and maillard reaction on color deterioration of ready-to-eat shrimps during storage

The mechanism of color deterioration in ready-to-eat (RTE) shrimps during storage was revealed for the first time. During storage, the appearance of the RTE shrimps gradually browned and blackened. Meanwhile, colorimeter analysis showed that the lightness decreased, but the redness and yellowness increased after storage. The peroxide and thiobarbituric acid value increased but the astaxanthin and phenol contents decreased after storage, indicating the occurrence of lipid and phenol oxidation. And the browning index, 5-hydroxymethylfurfural, pyrroles and pyrazine volatile compounds showed an upward trend after storage, indicating the occurrence of Maillard reaction. Correlation and principal component analysis showed that the composite effects of lipid oxidation, phenol oxidation, Maillard reaction and astaxanthin degradation led to the color deterioration of RTE shrimps, and the order of effect was Maillard reaction > lipid oxidation > phenol oxidation > astaxanthin degradation. Moreover, the lipid oxidation had a certain promoting effect on Maillard reaction and phenol oxidation.