Study Of Maturity Control Index System Establishment Of Red Wine Grape In Yangling Area

To a large extent,the flavor and quality of wine are determined by material compositions,but the biggest accumulation of sugar,polyphenol and aromatic substances cannot be obtained simultaneously.For ascertaining and optimizing the maturity of wine grapes,the Cabernet Sauvignon(CS),Merlot(ML),Meili(ME),(GA)and Pinot Noir(PN)5 red winegrapes varieties in YangLing of Shaaxi province were employed as testing subjects.We monitored the changes in berries compositions during fruit ripening,and also measured the quality of varietal wines made by different maturity of grapes.The main aim of this study is to model a system monitoring the maturity of red winegrapes cultured in YangLing of Shaaxi province.Based on the research can we draw the following conclusions.1.During veraison,the sugar content and pH increased and the acid decreased.the 100-weight was gradually increased in the mature stage and with small amplitude decreased in the ovemature stage.The change of polyphenol is complicated and have a big diversity in the different variety.The tendency of skin phenols is decline after first rise in GA,PN and ML grape,Mei Li(ME)and Cabernet Sauvignon(CS)the change is periodically.The change of seed phenolic is different from skin.Seed phenolic of GA grape is increased and trend steady in the post-maturation stage.In the PN grape,seed phenolic is increased first and then decreased.ML grape seed phenolic has an upward trend during maturity.CS and ME grape seed phenolic is increased first and then decreased and increased in the last time.2.With the delay of harvesting,the content of phenolic compounds in wine is increased.The wine with hightest concentration of phenols is GAW-3,PNW-2,MLW-2,MEW-3 and CSW-3.Sensory analysis showed that the sensory evaluation of GAW-3,PNW-3,MLW-2,MEW-4 and CSW-3 was highest.There is a positively correlation between wine phenolic contents with sensory quality in a certain range.3.According to the change of berries compositions,can we use principal components to calculate the fruit quality and obtain the weights of the indexes to established the 3-level index system to judging grape maturation.The One grade index of 5 red winegrapes varieties is the same as the sugar-acid ratio.Difference of Two and Three grade indexes in different varieties.GA grape Two grade index is Skin flavonoids,Three grade index is Skin tannin.PN grape Two grade index is Skin flavanols,Three grade index is Seed flavonoids;ML grape Two grade index is Seed total phenols,Three grade index is Skin tannin.ME grape Two grade index is Skin anthocyanin,Three grade index is Skin tannin.CS grape Two grade index is Skin flavonoids Three grade index is Seed flavonoids.When the fruit quality reaches the best,the range of 3-level index of Carnival fruit is 26-38,4-5mg and 0.9-2/respectively.When the fruit quality reaches the best,the range of 3-level index of GA grape is 26-38?4-5mg/g?0.9-1.2 mg/g respectively,PN grape is 20-30?3.0-6.5 mg/g?73-77 mg/g respectively,ML grape is 18-36?44-46 mg/g?2.7-4.1 mg/g respectively,ME grape is 25-42?2.6-3.5 mg/g?1.0-1.1 mg/g respectively,CS grape is 20-30?20-30 mg/g?55-71 mg/g respectively.