本文研究了电场辅助无定型橡木陈酿白兰地中多酚类物质的含量变化情况。为了加快无定型橡木制品中白兰地在的物理和化学反应速率,缩短白兰地的陈酿周期,研究了通过电场强化无定型橡木陈酿白兰地的陈酿过程,分析了多酚类物质随陈酿时间的变化规律。采用福林酚试剂法测定总酚和单宁;采用香草醛-盐酸法测定缩合单宁;HPLC法测定易挥发酚类物质。结果显示,采用电场强化技术对橡木进行处理,发现电场处理样的单宁及总酚含量都明显高于同期同容积自然陈酿样,浸泡橡木粉的电场处理样的总酚、总单宁含量比自然陈酿样在10 d时含量分别提高了10.03%、23.62%;浸泡橡木片时分别提高了18.41%、14.04%;浸泡橡木丁时分别提高了5.03%、9.70%;浸泡橡木块时分别提高了5.71%、20.03%。研究表明,电场作用可以明显促进白兰地对橡木中多酚类物质的提取,提升白兰地品质。
The changes in the content of polyphenols during electric field(EF)-assisted aging of brandy with amorphous oak were investigated in this study. To accelerate the physical and chemical reactions of brandy in amorphous oak and to shorten the maturation process, the aging process of brandy in amorphous oak enhanced by EF was studied, and the variations of polyphenol content over aging time were analyzed. The content of total phenols and tannins was determined by the Folin-Ciocalteu method; the content of condensed tannins was determined by vanillin-hydrochloric acid method and those of volatile phenols were determined by high-performance liquid chromatography(HPLC). The results showed that the content of total phenols and tannins of EF-treated oak samples was significantly higher than in untreated samples with the same aging period and volume. The content of total phenols in the EF-treated brandy sample aged with oak powder for 10 days was 10.03%, 18.41%, 5.03%, and 5.71% higher than in the control sample aged with oak powder, oak chips, oak cubes, and oak blocks, respectively. The content of total tannins in the EF-treated brandy sample aged with oak powder for 10 days was 23.62%, 14.04%, 9.70%, and 20.03% higher than in the control sample aged with oak powder, oak chips, oak cubes, and oak blocks, respectively. This study indicates that the extraction efficiency of polyphenol compounds from amorphous oaks can be enhanced by EF, thus improving the brandy quality.