| In this study, the content of phenolics in dry red wine of the east foot of Helan Mountain during 2 years wine aging period were measured by HPLC and the color characteristic indexes, CIELab, WCP and PPC, etc were also measured by using spectrophotometer.The changes of phenolics and the changes of color were reported the relation between these two factors was analyzed in order to see how phenolics affect and predict the stability of wine color. A theoretical basis of the relationship between wine color and phenolics was attempted to provide, so as to guide the fermentation in winemaking. The main findings are as follows:1. The initial levels of anthocyanins in differenet wines were similar and the contents of Mv-3-Glu was highest,and the lowest were Cy-3-Glu and Pn-3-Couglu,which contents of Mv-3-Glu was no more thanlOmg/L. Nine kinds of anthocyanins had similar trends of decreasing in aging period with the extension of aging time, which reached the lowest level in the 19th months of aging and then became stable.2. The total amount of colorless polyphenols descended from Cabernet Sauvignon and Merlot, Cabernet Gernischt, Pinot Noir to Shiraz. The proportion of catechin, gallic acid and salicylic acid exhibited the highest levels in new red wine. The content of colorless polyphenols was decreasing with the wine aging process while only the content of benzoic acid is rising.3. During the process of wine aging, color characteristics a* and Cab decreased gently and b*, Hab, PPC and wine tint raised. L* and wine chromaticity did not change much. WCP decreased after its initial rise.4. The CIELab color parameters and the content of phenolics during aging of different kinds of red wine were analyzed by using MLR and then a mathematical regression model between a*, b*, L* and Cab and phenolics were established with R values more than 0.9 indicating a good fitting. This can be used as a reference for wine color stability prediction in the future. |
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