Effect Of Lactobacillus Plantarum On The Deacidification And Quality Characteristics Of Kiwifruit Wine

Kiwi is widely planted on the north of QinLing in Shaanxi Province, and it showed obviously seasonal unbalance, and a hard question for long term storage. Kiwifruit wine can satisfy the customers’ requirement of fermented drinks trends, as one of the deep processing products. However, the high acidity has assive influence on the taste of kiwifruit dry wine. It has already been a restrict factor for the development of deep processing industry of kiwifruit.The aim of this paper was to study on the high acdity of kiwifruit wine, and 5 kiwifruit varieties: Qinmei, Xuxiang, Cuixiang, Huayou, Hort 16 A were used to brew kiwifruit wine. The physico-chemical characteristics of different kiwifruit fresh wines were measured, preliminary data suggested the differences of different varieties of kiwifruit wines. Preliminary discussion was based on the influence of kiwi fruit varieties on the organic acid varieties and the content of kiwifruit wine.Microbiological method was used for deacidification in kiwifruit wine. The deacidification was studied by inoculating different Lactobacillus plantarum(CS-1、XJA-2、XJ-14、XJ-25、520、542、544)into fresh kiwifruit wine. The aim of the study was to support industrial production.The major subject was as follows.(1)After the alcoholic fermentation, the physico-chemical characteristics of different kiwifruit fresh wines were measured experimentally in testing(kiwifruit varieties: Qinmei, Xuxiang, Cuixiang, Huayou, Hort 16A), controling the wine with 7 L.plantarum strains. The result suggested that Cuixiang and Xuxiang could be the better varieties for wine making, because of the difference of kiwifruit variety itself.(2) 7 different isolates of L.plantarum(CS-1, XJA-2, XJ-14, XJ-25, 520, 542, and 544) associated with the MLF were used in the study. By comparing the transforming ability of malic acid, growth curve and the rate of deacification in kiwifruit wine, L.plantarum 520 was screened as the considerable strain.(3) By conducting single factors and central composite design(CCD),the suitable levels were screened out for MLF. L. plantarum 520 was a considerable strain for kiwifruit wine deacidification. At the 0.05 significant level, the quadratic regression equation of the corresponding relation between experimental factors and response values of expressed by rate of deacification was achieved. And the centre point were 6.7 percent for inoculum size and pH 3.2 at 21.6℃. Under this optimizing condition, the rate of deacidification for malic acid achieved 63.89 percent.(4) The solid phase microextraction(SPME) and gas chromatographic-mass spectrometry(GC/MS) were introduced to determine volatile components. The varieties of aroma composition in kiwifruit wine were increased. Under controlled inoculation conditions, not only could MLF be shortened by half but, interestingly, enhancement of aroma complexity and flavour in kiwifruit wine enriched with a higher fruity note. In addition, important aromatic groups analysed here had not been previously described, thus affording deeper knowledge on aroma characterization of kiwifruit wine.