【作者】 侯爱香；

【导师】 周传云；

【作者基本信息】 湖南农业大学 ， 农产品加工及贮藏工程， 2007， 硕士

【摘要】 果醋是以水果或果品加工的下脚料为主要原料，经酒精发酵、醋酸发酵酿制而成的一种营养丰富，风味优良，保健作用突出的新一代酸性调味品或饮料。我国果醋历史悠久，几乎与果酒是同时代的产物，早在夏朝就开始有记载。随着人们生活水平的不断提高，果醋的保健功能也越来越受到人们的重视，国内正掀起喝果醋的热潮。有关果醋菌种、果醋工艺和果醋调配的研究也越来越受到研究者的青睐。本文主要包括四各方面的内容：(1)尝试以自然发酵果醋醪和果醋液为菌源，以AS1.41~*为对照菌株。通过初筛和复筛，筛选出G-6、G-7、Y-20三株较优的醋酸菌菌株。其产酸量均大于对照菌株的34.74g／L为：35.32g／L、35.55g／L、34.97g／L，且传代5次后性能稳定，醋酸分解速度小。产酯量分别达：0.872g／L、0.826g／L、0.847g／L。其最适发酵温度在32℃，耐酒精性、耐盐性能良好。并对三株菌进行初步鉴定，G-6属于醋化醋杆菌属，G-7为恶臭醋杆菌属，Y-20为液化醋杆菌属。(2)以从自然发酵的果醋醪中筛选出的产酸量和产酯量分别为：35.55g／L和0.826g／L的优良菌种G-7，作为出发菌株，采用紫外诱变、亚硝酸诱变以及紫外和亚硝酸诱变相结合的复合诱变，得出优良诱变菌株GUC-7，使产酸和产酯能力提高到42.36g／L和0.912g／L。(3)采用从自然发酵的果醋醪中选育出的优良菌株GUC-7进行果醋发酵，对果醋液态发酵和固态发酵工艺进行了比较，同时对固态发酵条件进行了优化设计，得出果醋固态发酵的最优条件组合，即酒精浓度在7％，接种量在10％，起始pH值为4.5的条件下进行果醋固态发酵，其成品的醋酸含量和酯含量分别是63.48g／L和0.998g／L。(4)直接发酵，不经调配稀释的果醋液，醋酸含量高，醋酸的刺激气味浓，果香味在酿造过程中有损失，不宜直接饮用。所以，选择合适的果醋饮料调配原料，对醋液进行调配，通过正交试验，确定最佳的调配配方即即苹果醋10mL／100mL，苹果汁8mL／100mL，蜂蜜4g／100mL，甜菊糖苷0.05g／100mL。更多还原

【Abstract】 The fruit vinegar takes the fruit or the reject and by-product of the fruit processing as themain raw material. It is a new nutritional acidic seasoning or drinking with unique flavor andhealthy care function through Ethyl alcohol and Acetic fermentation. The history of fruit vinegarin our country is glorious. It was appeared at the same time with the fruit cider long before. Asearly as Xia Dynasty, there was the record of the fruit vinegar. With the improvement ofpeople’s living standard, more and more people pay attention to the healthy care function of fruitvinegar and drink it. A lot of researchers pay more attention to the strain, the craft and the mixedof fruit vinegar.This paper mainly deals with four aspects of fruit vinegar:（1） This research takes the solid and liquid natural fermented fruit vinegar as the acetobactersource, takes the strain AS1.41*as contrast. Three superior acetobacter acetic strains G-6、G-7、Y-20 were selected. Their Acetic acid yield 35.32g/L、35.55g/L、34.97g/L were all higher thanthe Acetic acid yield of AS 1.41*34.74g/L. Their performances were steady after transplanting 5times. Their appropriate fermentation temperature was 32℃, their alcohol degree resistance andsalt resistance are all excellent. Their Ester content are 0.872g/L、0.826g/L、0.847 g/L.The resultof determination experiment is that: G-6 belongs to A.aceti.L, G-7 belongs to A. rancens.L,Y-20 belong to A.liquefaciens.L.（2） The original strain G-7 which was screening from the natural fermented fruit vinegar. ItsAcetic acid yield and Ester content were 35.55g/L and 0.826g/L. It was treated with Ultravioletradiation、HNO₂ and compound mutation technique（firstly by Ultraviolet radiation, then byHNO₂）. An excellent mutant strain namedGUC-7 was obtained. Its Acetic acid yield was42.36g/L and its Ester content was 0.912 g/L.（3） Used the strain GUC-7 in the fermentation of fruit vinegar, studied on the solid and liquidfermenting craft of fruit vinegar, at the same time, optimizing the fermentation conditions of thesolid fermenting craft and obtaining the best condition of the craft. The best condition is: alcoholdegree7％、inoculating amounts 10％、initial pH4.5. with this condition, the Acetic acid content and the Ester content are 63.48g/L and 0.998g/L in the fruit vinegar。（4） In the initial fruit vinegar fluid, the acetic acid content is high, the acetic acid penetratingodor is thick, and the fruit fragrance has loss in the process of fermentation, so it is not suitablefor drinking directly. Therefore, chooses the appropriate raw material to mix the fruit vinegarfluid. Through the orthogonal experiment, the research has determined the best formula to mix it.The best formula is: fruit vinegar 10ml/100ml, apple juice 8ml/100ml, honey4g/100ml,stevioside 0.05 g/100ml。更多还原