研究了葡萄汁和葡萄酒中总糖、乙醇和酒石酸的碳同位素特征,结果显示产地影响上述3类物质的碳同位素组成(δ13CVPDB值),4地区样品的总糖分布范围为-28.13‰~-23.25‰,乙醇的分布范围为-29.93‰~-24.23‰,酒石酸的分布范围为-24.49‰~-20.01‰;酒石酸与总糖的δ13CVPDB值之间呈线性正相关关系(R2=0.94),与乙醇的δ13CVPDB值的相关系数为(R2=0.96);模拟实验表明,葡萄汁中掺入甘蔗糖、葡萄酒中加入玉米酒精后,总糖和乙醇的δ13CVPDB值均随掺入量的增加而逐渐偏正,但酒石酸的δ13CVPDB值不变,而且也不受发酵的影响。选择酒石酸作为总糖和乙醇的碳同位素内源标志物可用于葡萄汁掺糖检测和“完全无添加”葡萄酒掺乙醇检测,文中也对比了不同检测模型的优劣。
Because of the restriction of stable carbon isotope ratio techniques, the database construction has become the premise of the application of stable isotope technique on evaluation of wine. Thus, stable isotope internal standardization has been a research focus of establishing isotope fingerprint in food field. In this study, the δ13CVPDB-values of tartaric acid and sugar in musts and the δ13CVPDB-values of tartaric acid and alcohol of corresponding wine have been measured. The δ13CVPDB values of tartaric acid in musts from four regions ranged from -24.48‰ to -20.02‰, the δ13CVPDB values of sugar in musts ranged from -28.13‰ to -23.25‰, the δ13CVPDB values of alcohol in alcohol fermentation ranged from -29.93‰ to -24.23‰. Meanwhile, good correlation (R2=0.94) were obtained between tartaric acid and sugar in musts. Also in alcohol fermentation, good correlation (R2=0.96) were obtained between tartaric acid and alcohol. Adding different proportions of C4 sugar to musts and alcohol to wines, the δ13CVPDB of sugar and alcohol displayed positive distribution, but δ13CVPDB of tartaric acid remained unchanged. The δ13CVPDB values of tartaric acid remained unchanged in alcohol fermentation(|Δ13CVPDB|<0.1‰). Based on this point, tartaric acid as internal standardization could be applied to identify the authenticity of must and "no-additive" wine. The recognition rate obtained by ratio model was higher than that by different model.