香草醛—盐酸法测定葡萄籽、梗中原花青素含量的研究

Vanillin-HCl Assay for the Proanthocyanidins Content of Grape Seed and Stem

国内外曾采用香草醛—盐酸法测定豆类物质中缩合单宁(原花青素)含量,但所用盐酸、香草醛浓度较高,显色时间长(15h),重现性差,有时甚至空白液也会发生颜色变化。本文针对测定葡萄籽和葡萄梗中原花青素含量的香草醛—盐酸法进行了改良,提出用低浓度香草醛、盐酸显色液测定原花青素含量,对改良前后的香草醛—盐酸法进行了比较。结果表明:改良后的香草醛—盐酸法测定葡萄籽、梗的原花青素准确性、重现性好。此方法简便、快速、易行,适合原花青素提取工艺的定性、定量研究。本法采用的盐酸浓度为4%,香草醛浓度为0.5%,显色时间为30min,显色温度为30±1℃。

The condensed tannin (proanthocyanidin) content of dry bean has been determined by the vanillin assay in theinternational research, but inadaptable to the test with higher respective concentrations of hydrochloric acid and vanillin thatwould result in too long time for color formation, bad reproducibility and sometimes even coloring the blank solution. The papertried to modify the vanillin assay on the content of proanthocyanidin of grape seed by puting on a new method with lowconcentration of hydrochloric acid and vanillin, as compared with the regular method.The modified method showed betterveracity and reproducibility on the determination of the contents of proanthocyanidin in grape seed and stem. This modifiedvanillin assay was quick、simple and easy to practise for the qualitative and quantitative study of the extraction ofproanthocyanidin. In this study, the concentration of HCl was 4%, vanillin 0.5%, incubation time for the color formation 30minand the temperature for color formation 30±1℃.