Effects of vineyard cover crops on main nitrogen compounds in grape berry and wine from vitis viniferal l. cv. cabernet sauvignon | 行间生草对赤霞珠葡萄与葡萄酒含氮化合物的影响

Chinese. 【目的】研究葡萄园行间生草对葡萄果实不同部位与葡萄酒中含氮化合物的影响。【方法】在酿酒品种赤霞珠葡萄园行间播种白三叶草、紫花苜蓿和高羊茅,以清耕为对照,在果实成熟期及酒精发酵结束后,采用凯氏定氮法及全自动氨基酸分析仪测定分析各处理葡萄果皮、果肉、种子及葡萄酒中的总氮、可溶性蛋白质及氨基酸含量。【结果】除紫花苜蓿处理使葡萄种子中可溶性蛋白质含量显著高于清耕(对照)外,行间生草总体使葡萄果皮、果肉及种子中的总氮和可溶性蛋白质含量降低,果实中不同部位总氮及可溶性蛋白质含量也有差异,种子中总氮含量最高,占葡萄果实总氮含量的41.6%,果肉与果皮分别占总氮含量的33.9%及24.5%;葡萄果实中可溶性蛋白质占总氮含量的46.0%,种子、果肉及果皮中可溶性蛋白质分别占果实中可溶性蛋白质总含量的50.9%、33.9%及15.2%;葡萄酒中总氮和可溶性蛋白质含量无显著差异。高羊茅和紫花苜蓿处理使葡萄果实中氨基酸总含量升高,白三叶草处理使其降低,但均无显著差异,各处理葡萄果实中均以脯氨酸含量最高,占氨基酸总含量的45.9%―56.9%,其次是赖氨酸和精氨酸,占氨基酸总含量的16.4%―24.2%。行间生草使葡萄酒游离氨基酸总含量升高,其中高羊茅处理最高,其次是紫花苜蓿处理,这两种生草处理与清耕之间差异达显著水平;各处理葡萄酒中的氨基酸,均以脯氨酸含量最高,占氨基酸总含量的90.11%―92.45%。【结论】行间生草使葡萄果实总氮和可溶性蛋白质含量降低,但总体提高了葡萄与葡萄酒中游离氨基酸总含量,有利于提高葡萄酒的质量。

English. 【Objective】 This study was conducted to determine the effect of inter-row cover crops in vineyard on main nitrogen compounds in grape berry (skin, pulp and seed) and wine from Cabernet Sauvignon. 【Method】 Compared with soil tillage (control), three cover crops, white clover, alfalfa and tall fescue were sown in vineyard. The main nitrogen compounds (total nitrogen, soluble protein and free amino acid) of mature grape berry (skin, pulp and seed) and wines vinified under the same conditions were extracted and analyzed with micro-kjeldahl method and full- automatic biochemical analyzer. 【Result】 The protein content in seed of alfalfa treatment was higher significantly than that of the soil tillage, and the total N and protein contents in skins, pulps and seeds decreased by different cover crops treatments. The total N content in seeds was the highest, which was 41.6% of the total N content in the whole berries, total N in pulps and skins accounted for 33.9% and 24.50% of the whole berries, respectively. While 46.0% of total nitrogen compounds in berries were proteins, the protein contents in seeds, pulps and skins were 50.9%, 33.9% and 15.2% of the total proteins, respectively. No significant difference was noticed among different treatments in total N content and protein content in wines. Compared to soil tillage, the alfalfa and tall fescue sward treatments increased the total amino acid contents of grape berry but the white clover treatment decreased them, and there was no significant difference between cover crop treatments and the control. Proline was the most abundant amino acid in grape berry in four treatments, which accounted for 45.9% to 56.9% of the total amino content, next in abundance was arginine and lysine, which accounted for 16.4% to 24.2% of the total amino acid content. The sward treatments showed a higher content of amino acid contents in wines, and there were significant differences (P＜0.05) between two cover crop treatments (tall fescue, alfalfa) and soil tillage. Praline was also the most abundant amino acid in wine, which accounted for 90.11% to 92.45% of the total amino acid content. 【Conclusion】 Cover crops in vineyard increased total free amino acid content of grape and wine, although decreased total N and protein content of grape berry. The conclusion is that the cover crops may improve the quality of wine.