Effect of temperature on the degradation of bioactive compounds of Pinot Noir grape pomace during drying

Abstract The objective of this study was to evaluate the effect of temperature and drying time on the total phenolic content and antioxidant capacity of grape pomace. Experimental data of the drying kinetics were fitted to six mathematical models and the Page model was selected as the most suitable to represent the drying of grape pomace. The best preservation of the phenolic compounds and antioxidant capacity was observed at 60 °C, suggesting that the temperatures of 40 °C and 50 °C were not sufficient to inactivate the enzyme polyphenol oxidase, being responsible for the greater degradation of these compounds.

**摘要** 本研究旨在评估温度与干燥时长对葡萄果渣总酚含量及抗氧化能力的影响。研究将干燥动力学实验数据拟合至6种数学模型中，最终选定Page模型作为描述葡萄果渣干燥过程的最优模型。实验结果显示，60℃条件下酚类物质与抗氧化能力的保留效果最佳，这表明40℃与50℃不足以灭活多酚氧化酶，进而导致此类物质发生更为显著的降解。