Influence of Different Sterilization Methods on the Physicochemical Properties, Functional Components and Metabolites of Grape Juice

This study systematically compared the impact of traditional pasteurization (TP), thermosonication combined with nisin (TSN), and irradiation (IR) on the physicochemical properties, functional components, and sensory quality of grape juice. In addition, widely targeted metabolomics was employed to assess changes in the metabolite profile. Results showed that TP significantly increased the viscosity of the juice and led to noticeable color deterioration (PPα-linolenic acid and γ-linolenic acid) and essential amino acids (leucine and isoleucine), and the marked accumulation of furfural derivatives such as 2-furoic acid, which ultimately contributed to nutrition and flavor deterioration. TSN and IR had limited effects on organic acids, unsaturated fatty acids, and phenolic compounds, but IR led to a marked down-regulation of specific anthocyanin monomers, including cyanidin-3-O-glucosylrutinoside and cyanidin-3-O-rutinoside-5-O-glucoside. In summary, IR outperformed thermal sterilization in enhancing the sensory quality and preserving the stability of functional components in grape juice, demonstrating its superior processing adaptability and application potential. These results provided theoretical basis and technical references for the high-value processing of grape juice.