通过分析发酵对苹果品质影响的内在机制，为苹果功能成分及代谢调控机制提供科学依据，助力苹果产业纵深发展。采用非靶向代谢组学技术分析了高温高湿条件下苹果加工过程产生的各类差异代谢化合物，分别使用主成分分析方法、聚类热图、偏最小二乘判别方法、KEGG 通路富集等对代谢组数据进行分析。结果表明，通过主成分分析(PCA)显示了不同发酵过程中苹果代谢组成的显著阶段性变化，代谢物质鉴定表明，存在334种代谢物，其中脂质和类脂分子所占比例最大，达到44.61%。利用聚类树图和正交偏最小二乘判别分析(OPLS-DA)揭示了在发酵末期苹果样本的代谢物水平明显高于未发酵样本，有效地区分了不同发酵阶段的苹果样本。通过KEGG路径分析进一步指出，苹果的苯丙素生物合成和苯丙氨酸代谢途径在发酵期间非常活跃，并且在高温条件下激活了玉米素生物合成和鞘脂代谢的特定途径，这对苹果的高温适应性和风味的形成具有重要影响。

By analyzing the intrinsic mechanisms of how fermentation affects apple quality, this study provides a scientific basis for the functional components and metabolic regulation mechanisms of apples, supporting the in-depth development of the apple industry. In this research, non-targeted metabolomics technology was utilized to analyze the diverse differential metabolic compounds generated during the processing of apples under high temperature and high humidity conditions. Various methods such as principal component analysis(PCA), cluster heat maps, partial least squares discriminant analysis(PLS-DA), and KEGG pathway enrichment were utilized to evaluate the metabolomic data. PCA revealed significant stage-wise changes in the metabolic composition of apples during different fermentation processes. Metabolite identification indicated the presence of 314 metabolites, with lipids and lipid-like molecules accounting for the largest proportion, reaching 44.61%. Utilizing cluster dendrograms and orthogonal partial least squares discriminant analysis(OPLS-DA), it was revealed that the metabolite levels in the apple samples at the end of fermentation were significantly higher than those in the unfermented samples, effectively distinguishing apple samples at different fermentation stages. Further, KEGG pathway analysis pointed out that the biosynthesis of phenylpropanoids and the metabolism of phenylalanine in apples were very active during fermentation, and specific pathways for the biosynthesis of cornoside and sphingolipid metabolism were activated under high temperature conditions, which have an important impact on the high-temperature adaptability and flavor formation of apples.

S661.1；TS207.3

甘肃省农业农村厅科技项目(GNKJ-2022-29)；国家苹果产业技术体系(CARS-27-2024)；甘肃省科技计划项目(23JRRA1792)。