橡木提取液对霞多丽和赤霞珠葡萄果实品质的影响

Effect of Oak Extracts on the Quality of Chardonnay and Cabernet Sauvignon(Vitis vinifera L.) Grape Berries

主要研究橡木提取液对葡萄果实品质的影响。以欧亚种(Vitis vinifera L.)酿酒葡萄品种赤霞珠和霞多丽为实验材料,外源喷施橡木提取液后测定果实单宁、多酚、花色苷、单糖和有机酸单体含量及香气成分的质量浓度。结果表明:橡木提取液对葡萄果实基本理化性质影响不显著,橡木提取液可提高霞多丽果实总酚和单宁含量,其中体积分数25%美国橡木提取液处理组单宁含量比对照组(喷蒸馏水,下同)增加了33.2%;橡木提取液可提高赤霞珠果实单宁和总花色苷含量,与对照组相比,体积分数25%美国橡木提取液处理后赤霞珠单宁含量增加了40.7%,纯美国橡木提取液处理后花色苷含量增加了10.7%;纯橡木提取液可以提高霞多丽和赤霞珠果实果糖含量;橡木提取液可以提高霞多丽和赤霞珠果实葡萄糖含量。橡木提取液对霞多丽和赤霞珠果实香气成分有很大影响,都增加了果实香气成分的种类,尤其是酯类、醛类和醇类(如橡木内酯、四氢薰衣草醇),同时可增加果实香气质量浓度,如体积分数25%美国橡木提取液可使6-甲氧基丁子香酚的质量浓度增加近8倍。外源喷施橡木提取液可改善葡萄果实品质,结果可为葡萄产业废弃物开发利用提供理论依据。

In this paper, the effects of oak extracts on grape berry quality were studied, with the aim to make full use of oak waste. Cabernet Sauvignon and Chardonnay grapes were used as research materials. Oak extracts were sprayed onto grape berries at the early stage of veraison and the contents of tannins and polyphenols and anthocyanins in ripe grapes were determined with a spectrophotometer. Besides, the contents of monosaccharides and organic acid monomers were determined by high performance liquid chromatography（HPLC） and volatile aroma compounds were analyzed by gas chromatography-mass spectrometry（GC-MS）. The results showed that oak extracts had no significant effect on physical and chemical properties but increased the total phenols and tannin contents of Chardonnay berries. Among the extracts evaluated, 25% American oak extract could result in a 33.2% increase in tannin content when compared with the control group. The oak extract could increase the contents of tannin and total anthocyanin of Cabernet Sauvignon berris, 25% American oak extract could result in a 40.7% increase in tannin content when compared with the control group, and pure American oak extract increased the anthocyanin content by 10.7%. Pure oak extracts elevated the fructose content in both varieties. Moreover, oak extracts resulted in increased glucose contents in the two varieties. Oak extracts had a significant impact on fruit aroma components in Chardonnay and Cabernet Sauvignon. The contents and types of aroma components especially esters, aldehydes and alcohols were increased after treatment. For instance, 25% American oak extract increased the concentration of 6-methoxy eugenol by 9 folds. In conclusion, exogenous oak extract could improve grape fruit quality. These results will provide a theoretical basis for the development and utilization of grape industrial processing wastes.