| Wild kiwi was a clean,natural green fruit, however, compared with the cultural kiwi, wild kiwi was small and poor shape. It has not been found a way which could utilize its value,so the price was very low. Brewing wine with wild kiwi was characteristic project of agriculture through science and technology; it would be propitious to adjust the agricultural structure and increase farmers'income, and promote the development of characteristic agricultural products processing industry; it also was a way which make the wild kiwi to leave the mountain and go toward to the market increasing added value. Wild kiwi wine also benefited the nation and the people, had important economic significance.The wild kiwifruit in Fu-niu Mountains was used as the material in the article, key step of wild kiwi wine brewing was researched, the results were as follows:1.The average weight of wild kiwifruit was 17g, and the saccharinity was 69.76g·L-1 , but the acid content was 17.47g·L-1 and the content of Vc was 994.4mg·kg-1, so wild kiwifruit could be brewed after ajusting its composition. The maturity of wild kiwifruit was determined by measuring the hardness using Texture Analyser for the first time. The research showed that the saccharinity would increase as the hardness degrade, wild kiwifruit maturity could be determined by measuring the hardness. Storage under 25℃for 4-5 days could effectively reduce the hardness of wild kiwifruit.2.The wild kiwi wine was suitable for fermentation of clarified juice, in order to improve the quality of wild kiwifruit juice, the yield of juice and the content of Vc was indicator, hydrolysis conditions were optimized by orthogonal test, enzymatic effect was compared between pectinase and pulp enzyme. The result showed that the technology of pectinase was intensive, the yield of juice was high, but the content of Vc was saved poor; the pulp enzym hydrolysis process was mild, the yield of Vc was saved well, the color and aroma of the juice losed little, it was more suitable for preparation of juice. The optimized conditions of pulp enzyme: zymolysing temperature 30℃, add enzyme quantity 0.5 mL·kg-1, zymolysing time 2h, the yield could achieve to 0.852mL·g-1 and the preservation rate of Vc achieved 67%. Six clarifiers were used to clarify the juice, the settled effects were compared and found all clarifiers could increase the clarity of wild kiwi juice, but the combination of all factors, using 0.2g·L-1 of 1% gelatin as the clarifier, which could make the clarity of wild kiwi juice reached 98% after 12h.3. In order to optimize the fermentation process of wild kiwi wine, fermentation conditions were determined by single factor experiments and response surface optimization: the innoculation 1.0‰, the fermentation temperature 21.2℃, the amount of SO2 98.1mg·L-1. Under these conditions, the wine was clear and transparent with flavo-green.the fragrance was full and good with evident kiwifruit aroma, the taste was mellow and supple.4. In order to reduce the acid content of wild kiwi wine, natural deacidification and chemical deacidification were used to reduce acid in the wine. Natural deacidification would cost a long time and drop less, the acidity reduced 1.97g·L-1 in forty-two days; chemical deacidification could achieve a better result, using potassium tartrate and potassium carbonate could achieve a good effect.5. In order to test the stability of the wild kiwi wine aroma, the wild kiwifruit new wine, the wine aged for six months and one year aged wine samples were detected by GC / MS, the aroma components in wild kiwi wine mainly were alcohol and ester, and a number of alkanes. There were 9 kinds of aroma between the new wine and the wine aged for six months and 10 kinds of aroma between the new wine and the wine aged for one year was same, while there were 18 kinds of aroma between the wine aged for six months and one year aged wine was same, there were 8 kinds of aroma in the three wine samples was same, the wild kiwifruit wine would become more stable after storage.
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