【作者】 张如金；

【导师】 李华；

【作者基本信息】 西北农林科技大学 ， 食品科学， 2008， 硕士

【摘要】 苹果酸-乳酸发酵(Malolactic Fermentation, MLF)是葡萄酒中非常重要的二次发酵过程。在葡萄酒制造发达国家,大都用商业活性乳酸菌进行苹果酸-乳酸发酵。迄今为止,国外如法国、美国、澳大利亚等国对MLF和活性乳酸菌进行了较为深入的理论探讨和实际应用,而我国在这一领域的研究特别是活性乳酸菌干粉的研究工作开展得较少。为此,本研究利用西北农林科技大学葡萄酒学院优选酒类酒球菌SD-2a制备成活性干粉,对产品作质量检测,并与法国LAFFORT公司生产的450PreAc干粉和丹麦CHR HANSEN公司生产的OENOS干粉,在宁夏广夏贺兰山葡萄酿酒有限公司生产条件下进行MLF,研究这三种干粉对酒质的影响,比较其生产性能,研究结果表明:1.酒酒球菌SD-2a干粉产品的色泽为浅黄至浅棕色,形状为粉状或颗粒状,并具有乳酸菌特殊的气味,无异味,无杂质。感观分析结果完全符合产品的预期要求。产品的技术中活细胞数高于1×1011cfu/g ,水分含量小于5%。葡萄酒乳酸菌发酵剂的卫生指标全部符合要求,特别是活细胞数远远超过了同类产品的技术要求。2. SD-2a活性干粉、450PreAc和OENOS干粉及对照酒样经MLF后,总酸、挥发酸和pH等成分含量均发生显著变化,其中总酸含量分别降低18.6%,16.4%,11.7%和2.9%;挥发酸含量都有所上升,上升幅度在0.23～0.39g/L, SD-2a的升高值最高为0.39 g/L,其次是OENOS和450PreAc,分别为0.25 g/L和0.23 g/L,但各酒样最终挥发酸含量均低于国际标准。3.在MLF后,相对于对照酒样中其他酒样中总酚的含量有所升高,升高值在0.23-0.45 g/L之间,其中SD-2a的升高值最大,为0.45 g/L,依次是OENOS和450PreAc,分别是0.33 g/L和0.23 g/L。4.各菌种进行MLF后的葡萄酒口感变得柔和、润口、协调,酒质得到提高,其中SD-2a、450PreAc酒质较好,其次是OENOS和对照。5.酒酒球菌SD-2a干粉在生产条件下进行MLF后总酸含量显著下降,微生物的稳定性增加。同时,提高了酒中总酚的含量,有利于风味复杂性的形成。同时经济利益上考虑,在与国外干粉的用量相同的情况下,每千克的成本要比国外干粉的价格降4000-5000元,有利于企业节约成本。本试验表明酒酒球菌SD-2a活性干粉具有优良的生产性能,适合于生产中推广应用。更多还原

【Abstract】 Malolactic fermentation(MLF) is indispensable processing technology for modern wine making. In developed wine making countries, most of the vineries use commercial freeze-dried LAB to inoculate MLF. So far, foreign countries like France、The US and Australia have done deeply research on MLF and active dry poeders. But in our country, research on this is scarcely. So, this paper studied on quality test of freeze-drying Oenococcus oeni SD-2a active dry powder. Effects of performance trait in and after malolactic fermentation (MLF) on dry red wine were also studied with Oenococcus oeni SD-2a active dry powdr, 450PreAc dry powder and OENOS dry powder. The results indicated:1. The quality of the Oenococcus oeni SD-2a dry powder was measured. The results showed that the quality of sensory analysis, technical index and hygiene index all measured up, and also met the international standard of similar products.2. The content of total acid, volatile acid and pH changed significantly after MLF. Reduction rates of total acid were 18.6%(SD-2a), 16.4%(450PreAc), 11.7% (OENOS) and 2.9% (CK), respectively. The content of volatile acid are on the rise,Increase values are 0.39 g/L(SD-2a),0.25g/L(OENOS)和0.23 g/L(450PreAc) and 0.08 g/L (CK),bue all the values are under the international standard.3. The content of total phenols are on the rise,Increase values are 0.45 g/L (SD-2a),0.33 g/L (OENOS)和0.23 g/L(450PreAc) and 0.04g/L (CK).4. After MLF wine taste soft , coordination, wine quality is improved, SD-2a and 450PreAc are better, followed by OENOS and CK.5. Oenococcus oeni SD-2a dry powder has a significant drop of total acid content under the conditions of production after MLF, increases the stability of micro-organisms. At the same time, enhances the contents of the total phenols, which is conducive to the formation of complex flavor. At the same time economic interests is considered, the cost per kg of dry powder is 4000-5000 yuan lower thanforeign dry powders, which is beneficiala for wineries cut costs. This test shows that Oenococcus oeni SD-2a dry powder has an excellent performance trait and is suitable for application in production.更多还原