Flavonol Profiles of Vitis vinifera Red Grapes and Their Single-Cultivar Wines
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- 作者：Noelia Castillo-Muñ ; oz ; Sergio Gó ; mez-Alonso ; Esteban Garcí ; a-Romero ; Isidro Hermosí ; n-Gutié ; rrez
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2007
- 出版时间：February 7, 2007
- 年：2007
- 卷：55
- 期：3
- 页码：992 - 1002
- 全文大小：175K
- 年卷期：v.55,no.3(February 7, 2007)
- ISSN：1520-5118
文摘
The main flavonols found in seven widespread Vitis vinifera red grape cultivars include the 3-glucosidesand 3-glucuronides of myricetin and quercetin and the 3-glucosides of kaempferol and isorhamnetin.In addition, the methoxylated trisubstituted flavonols, laricitrin and syringetin, were predominantlyfound as 3-glucosides. As minority flavonols, the results suggest the detection of the 3-galactosidesof kaempferol and laricitrin, the 3-glucuronide of kaempferol, and the 3-(6' '-acetyl)glucosides ofquercetin and syringetin. The flavonol profiles based on the eight above-mentioned flavonols allowedthe cultivar differentiation of the grape samples. With regard to flavonol biosynthesis in the berryskin, quercetin 3-glucuronide predominated at véraison, followed by quercetin 3-glucoside, and onlytrace amounts of trisubstituted flavonols were detected. The proportion of quercetin 3-glucosideremained almost constant during berry ripening, whereas the proportion of quercetin 3-glucuronidedecreased and the other flavonols, especially myricetin 3-glucoside, increased their importance. Inwines, flavonol 3-glycosides coexisted with their corresponding free aglycones released by hydrolysis.The presence of laricitrin, syringetin, and laricitrin 3-glucoside in red wines is reported here for thefirst time. The extent of hydrolysis was widely variable among wines made from the same grapecultivar, and the results suggest the influence of the type of aglycone and glycoside on the rate ofhydrolysis. Due to hydrolysis, the differentiation of single-cultivar wines gave acceptable results onlywhen aglycone-type flavonol profiles were used.