Methanol Mitigation in Kiwifruit Wine Fermentation Through Process Regulation: Effects on Physicochemical Properties...

Methanol formation is a critical safety concern in kiwifruit wine due to the high pectin content of kiwifruit. This study aimed to establish an effective strategy to reduce methanol formation while maintaining the fermentation performance and sensory quality of kiwifruit wine. The effects of fermentation temperature, pectinase dosage, and clarification centrifugation conditions on methanol production were investigated, and the selected process-regulation strategy was further evaluated by analyzing physicochemical properties, volatile aroma compounds, and sensory characteristics. The results showed that pectinase dosage was the predominant factor affecting methanol formation. Under the selected process conditions identified within the tested parameter ranges (fermentation at 19 °C, pectinase dosage of 0.02 g/L, and centrifugation at 2500 r/min), the methanol content decreased to 167.45 ± 2.20 mg/L, representing a 37.39% reduction compared with the control group, while the ethanol content remained at 12.66 ± 0.04% (v/v). Moreover, the wine exhibited favorable physicochemical characteristics, including improved retention of phenolic compounds and balanced organic acid composition. Aroma profiling using GC-MS and multivariate statistical analysis demonstrated that the optimized wine exhibited a volatile aroma pattern comparable to that of the control wine, indicating that methanol mitigation did not substantially impair the characteristic flavor of kiwifruit wine. Sensory evaluation further confirmed the improved overall acceptability of the processed product. This study provides a practical approach to producing safer kiwifruit wine while preserving quality attributes.