两个品种桃蒸馏酒中甲醇含量差异性研究

为探究两个品种的桃蒸馏酒中甲醇含量的差异性，分别取不同采摘时期的两个桃子品种进行蒸馏酒的制作，采用气相色谱（GC）法测定桃蒸馏酒中的甲醇含量；并测定了两个品种桃果实的基本理化指标、多聚半乳糖醛酸酶（PG）活性、果胶酯酶（PE）活性及果实中的果胶含量；分别分析了甲醇含量与PG活性、PE活性及果实中果胶含量的相关性情况；并采用模拟发酵试验的方法进一步探究果胶含量及果胶酶含量对甲醇含量的影响。结果表明，两个品种桃蒸馏酒中甲醇含量差异大的原因主要与果实的PG活性、PE活性及果实中的可溶性果胶含量和原果胶含量显著相关（P＜0.01），与果胶总含量无显著相关性（P＞0.05）；且模拟发酵试验证明了果胶含量和果胶酶活性是甲醇产生的重要途径之一。

Differences of methanol contents in distilled liquors from two varieties of peach

In order to explore the difference of the methanol contents in distilled liquors from two varieties of peach, the distilled liquors were prepared using two varieties of peaches with different picking periods, and the methanol contents in the distilled liquor were determined by gas chromatography (GC). The basic physical and chemical indexes, polygalacturonase activity, pectinesterase activity and pectin contents in two varieties of peach fruits were also determined. The correlation between methanol contents and polygalacturonase activity, pectinesterase activity and pectin contents in two varieties of peach fruits were analyzed. The effects of pectin contents and pectinase contents on methanol contents were further explored by simulated fermentation test. The results showed that the reasons for the large difference in methanol contents between two varieties of distilled liquor were significantly correlated with the activity of polygalacturonase and pectinesterase, soluble pectin contents in fruits (P＜0.01), and there was no significant correlation with the total pectin contents (P＞0.05). The results of simulated fermentation test showed that pectin contents and pectinase activity were one of the important ways to methanol production.