Effect of Bagging on the Contents of Sugar, Free Fatty Acids, and Volatile Compounds in Peach Fruit

To investigate the effect of bagging on the fruit quality of ‘Honghuayingzui’ peach, gas chromatography-tandem mass spectrometry (GC-MS/MS) was used to analyze the metabolite profiles of bagged and unbagged peach fruits. The results showed a total of 634 metabolites were identified, including 11 sugars, 33 free fatty acids, and 590 volatile compounds. Among these, 107 significantly differential metabolites were identified, including 59 up-regulated substances and 48 down-regulated substances. Compared with the non-bagged group, the bagged fruit exhibited improved appearance quality and significantly reduced contents of sorbitol and oleic acid (P < 0.05). Additionally, the bagged fruit had a greater diversity of volatile compounds, with a weakened green aroma but enhanced floral, fruity and sweet aromas. However, no significant differences (P > 0.05) were observed in sweetness, total sugar, total free fatty acid, or total volatile compound contents. This study provides an important theoretical basis for improving the quality of bagged peach fruit.