采用超高效液相色谱-四极杆-飞行时间-质谱法,研究2种酵母Red Fruit和Zymaflore ST分别在'北冰红'和'威代尔'冰酒的发酵过程中,对不同糖苷态香气物质含量的影响,以及瓶储1年后葡萄酒中糖苷态香气物质含量的变化.结果表明,'威代尔'冰酒中有更丰富的糖苷态香气物质种类和含量.酵母Red Fruit和Zymaflore ST发酵的'北冰红'冰酒中,戊糖基-葡萄糖苷类香气物质均略有下降,但酵母Zymaflore ST发酵对己糖基-葡萄糖苷类香气物质影响不显著.酵母Zymaflore ST发酵'威代尔'冰酒中,戊糖基-葡萄糖苷、己糖基-葡萄糖苷和葡萄糖苷类的香气物质均显著降低,而酵母Red Fruit对糖苷类型的香气物质均无显著影响(己糖基-葡萄糖苷类除外).瓶储1年后,'北冰红'冰酒中各种糖苷态香气物质含量均大幅降低.研究认为,酵母Red Fruit和Zymaflore ST对发酵过程中'北冰红'糖苷态香气释放影响很小,糖苷态香气释放可能主要在陈酿阶段,而酵母Zymaflore ST发酵较有利于'威代尔'糖苷态香气的释放.该结果为冰酒的酿造和陈酿工艺设计提供了参考.

Glycosylated volatile precursors are important, particularly in wine grape berries, as they contribute to the final aroma in wines by releasing volatile aglycones during yeast fermentation and wine storage. Previous study demonstrated that VviGT14 was functioned as a critical monoterpene glucosyltransferase in grape berry, while the transcriptional regulation mechanism ofVviGT14was still unknown. Here we identified VviWRKY40 as a binding factor ofVviGT14promoter by both DNA pull-down and yeast one-hybrid screening, followed by a series of in vitro verification.VviWRKY40expression pattern negatively correlated with that ofVviGT14in grape berries. And the suppressor role of VviWRKY40 was further confirmed by using the dual luciferase assay with Arabidopsis protoplast and grape cell suspension system. Furthermore, the grape suspension cell ABA treatment study showed that ABA downregulatedVviWRKY40transcript level but promoted that ofVviGT14, indicating that VviWRKY40 was at the downstream of ABA signal transduction network to regulate monoterpenoid glycosylation. These data extend our knowledge of transcriptional regulation ofVviGT14, and provide new targets for grape breeding to alter monoterpenoid composition.