HE Jing, CHEN Qiling, ZHANG Wanxue’er, CHEN Yingjie, FANG Xin, JIAN Dongming, BAI Hexiang, YANG Xingyuan
To investigate the influences of exogenous Zn2+ with different addition dosages on the color stability of Cabernet Sauvignon dry red wine during aging, Cabernet Sauvignon dry red wines supplemented with exogenous Zn2+ at contents of 0, 2.5, 5.0, 7.5, 10.0 and 20.0 mg/L, respectively, originating from two producing regions, Yili (YL) and Heshuo (HS) in Xinjiang, China, were selected as research materials. All samples were aged at 20 ℃ in the dark for 9 months, and variations in basic physicochemical indexes, total phenols, total anthocyanins and color parameters were determined periodically. The results showed that the physicochemical indicators of wine samples from both regions complied with relevant national standards. With prolonged aging, the contents of total phenols and total anthocyanins declined in all treatment groups, accompanied by decreases in color intensity and a* value, as well as rises in colour shade, L* value, b* value, C*ab value and hab value. At Zn2+ content of 20.0 mg/L, total phenol contents of YL and HS wine samples aged for 9 months decreased by 957.21 and 910.12 mg/L, total anthocyanin contents dropped by 188.51 and 172.30 mg/L, color intensity reduced by 6.62 and 6.49, a* value declined by 0.81 and 0.88; meanwhile, b* value increased by 6.38 and 6.30, C*ab value rose by 4.65 and 4.51, and hab value elevated by 1.13° and 0.97°, respectively, compared with the samples aged for 1 month. The declines in color intensity and L* value indicated a paler, less bright appearance, while elevated C*ab value reflected the accumulation of yellowish-brown substances. These changes reflect typical color aging phenomena: a reduction in red hue and enhancement of yellow hue, degradation of anthocyanins into yellowish-brown polymers, and a shift in wine color from purplish-red to brick-red/brownish-yellow. In conclusion, exogenous Zn2+ accelerated the color aging process of Cabernet Sauvignon dry red wine within a certain addition concentration range.
