Abstract:

In order to study the effects of different concentrations of γ-aminobutyric acid（GABA）treatments on the quality and antioxidant system of cherry tomato. In this study，‘Seoul Red’cherry tomato was used as experimental material and soaked in GABA solutions at concentrations of 0，25，50，75 and 100 mmol · L^-1. Regular measurements were conducted on indicators including fruit decay index，weight loss rate，firmness，nutritional quality（soluble sugar，vitamin C，soluble solids，titratable acid，etc.），and antioxidant enzyme activities （POD，PPO，CAT，SOD，LOX，PAL）. Additionally，models such as principal components analysis（PCA），entropy weight method（EWM），and entropy weight-TOPSIS were used to comprehensively evaluate the preservation effects. The results showed that the 75 mmol · L^-1 GABA treatment group significantly reduced the fruit weight loss rate and decay index，delayed the decline in firmness，and maintained higher levels of soluble sugar and vitamin C content. Meanwhile，it significantly enhanced the activities of POD，PPO，CAT，and SOD，reduced MDA content and LOX activity，thereby slowing down the fruit post-ripening and senescence process. PCA extracted three principal components with a cumulative contribution rate of 86.87%；the entropy weight method identified CAT activity and sugar-acid ratio as key indicators；entropy weight-TOPSIS showed that the relative closeness of the 75 mmol · L^-1 GABA group was the optimal. The 75 mmol · L^-1 GABA group significantly prolongs the shelf life of fruits and maintains better quality. Therefore，exogenous GABA treatment is a feasible postharvest preservation technology for cherry tomatoes.

Key words: cherry tomato, γ-aminobutyric acid, postharvest preservation effect, antioxidant enzyme activity, comprehensive evaluation