Abstract:

【Objective】 This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. 【Method】 Three such cover crops, two perennial legumes (white clover and alfalfa) and a perennial gramineous grass (tall fescue) were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and trichloromethane and analyzed by high-performance liquid chromatography (HPLC) and compared with that in soil tillage. 【Result】 A total of 10 phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids (hydroxybenzoic and hydroxycinnamic acids) and flavonoids (flavanols and flavonols). The concentration of flavonoid compounds (409.43 to 538.63 mg?kg-1 and 56.16 to 81.30 mg?L-1) was higher than nonflavonoids (76.91 to 98.85 mg?kg-1 and 30.65 to 41.22 mg?L-1) for Cabernet Sauvignon grape and wine in different treatments. In the flavonoid phenolics, catechin was the most abundant in different grapes and wines, accounting for 74.94% to 79.70% and 48.60% to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments (tall fescue, white clover) and soil tillage in the content of benzoic acid, salicylic acid, caffeic acid, catechin and total phenolics in grape berry (P＜0.05 or P＜0.01). The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments: tall fescue, white clover, alfalfa and soil tillage (control). 【Conclusion】 Cover crop in vineyard increased total phenols of grape berry and wine, thus improved the quality of wine evidently.

Key words: vineyard')">vineyard, cover crops inter-row, Cabernet Sauvignon grape berry, wine, monomeric phenols