【作者】 雷蕾；

【导师】 任发政；

【作者基本信息】 中国农业大学 ， 食品科学， 2004， 硕士

【摘要】 本课题采用无盐渍法新工艺制作Mozzarella干酪，研究了不同发酵剂、不同凝乳酶、凝乳酶的不同添加量及不同凝乳时间对Mozzarella干酪品质的影响，筛选出发酵剂及凝乳酶的最适用量和生产的最佳工艺，为实现干酪的工业化生产，建立最佳工艺参数。 通过比较单一嗜热链球菌发酵剂，嗜热链球菌和德氏保加利亚乳杆菌混合发酵剂，研究发酵剂对Mozzarella干酪化学成分和功能特性的影响。实验结果表明两种发酵剂影响Mozzarella干酪的品质。不同发酵剂对干酪化学成分没有影响。在成熟期里，混合菌在干酪中的蛋白水解速率高于球菌的蛋白水解速率。成熟后，混合发酵剂干酪比单球菌干酪有更柔软的质地，更大的融化性，更多的油脂析出。结合感官评分，认为混合发酵剂更适合pizza专用Mozzarella干酪的生产。 通过对三种不同来源的凝乳酶即小牛皱胃酶，混合酶和微生物酶对Mozzarella干酪化学成分、蛋白水解及功能特性的影响研究。表明不同凝乳酶对成品干酪的蛋白质和脂肪含量有影响，微生物酶制干酪比小牛皱胃酶和混合酶有更高的蛋白含量和更低的脂肪含量。在贮藏期里蛋白水解会受凝乳酶类型显著影响。微生物酶制干酪的蛋白质水解度最大，且水解模式异于小牛皱胃酶和混合酶。酶类型对干酪的硬度，弹性没有显著影响，对融化性和油脂析出性有显著影响。在相同条件下，未融化时微生物酶生产的干酪硬度和弹性低于小牛皱胃酶和混合酶生产的干酪。在融化时，则有更大的融化性和更多的油脂析出。小牛皱胃酶制干酪品质与微生物酶干酪品质相似。根据生产成本和干酪品质综合分析，混合酶是最理想得凝乳酶。 实验分别添加22mg／kg、25mg／kg、28mg／kg的凝乳酶，结果表明，凝乳酶的添加量影响干酪的水分和蛋白质含量。凝乳酶添加量越高，蛋白质含量越高，水分含量越低。干酪的硬度、融化性和油脂析出越高。但过多的凝乳酶会造成千酪有更大的蛋白水解，使干酪有苦味。因此25mg／kg的添加量适最是添加量。 凝乳时间分别为30分钟，40分钟，50分钟。凝乳50分钟的干酪比凝乳40分钟和30分钟的干酪有着更高的水分含量，更低的脂肪含量。凝乳50分钟和40分钟的干酪比凝乳30分钟的干酪有着更好的弹性、融化性和油脂析出，同时也具备了更柔软，更光滑均匀的质地。结合感官评分，认为40分钟的凝乳时间是最佳凝乳时间。更多还原

【Abstract】 This dissertation researched the effects of culture starter, coagulant type, amount of coagulant and coagulum time on the quality of mozzarella cheese for pizza. A "no-brine" Mozzarella cheese process was used to mike cheese for homogeneous chemical composition. The ultimate goal is to screen the optimum culture stater and coagulant. And get the optimum addition amount of coagulant and clotting time.This dissertation compares the effect of two kinds of cultures on Mozzarella cheese. One is single strain of Streptococcus salivarius ssp. Thermophilus; the other is a pair of Lactobacillus debrueckii ssp. Bulgaricus and Streptococcus salivarius ssp. Thermophilus. There is no effect of culture staters on cheese chemical composition. During ripening, the rate of proteolysis of the cheese made with pairs strain culture is higher than that of the cheese made by single strain culture. The meltability and free oil release of cheese made with pairs strain culture is better than that of the cheese made by single strain culture.The cheeses were made with three different coagulant types (rennet, mixture coagulant, microorganism coagulant): The results showed coagulant types have affected cheese protein and fat levels. During storing the rate of proteolysis is remarkably affected by coagulant types. The rate of proteolysis in the cheese made with microorganism coagulant is the fastest, and the pattern of proteolysis of microorganism is different from rennet and mixture coagulant. The coagulant types only remarkably affect the meltability and the free oil release. On the same condition, before melting the hardness and springness of cheese made with microorganism coagulant is lower than that of other two cheeses, but during melting it’s meltability and free oil release is the best.In research of addition amount of rennet, I designed that the addition amount was 22mg/kg, 25mg/kg, and 28mg/kg separately. The results showed the addition amount of coagulant affect chemical composition especially moisture and protein content. If the addition amount of coagulant is higher, thecoagulation ability is better and the content of protein is higher .The defect of this cheese is mouthfeeling bitter. The more addition amount of coagulant is, the higher values of hardness meltability and free oil release of cheese are.Three firmness levels were tested, and these corresponded to average time of coagulum addition to cutting the curd of 30, 40,50min clotting. With the clotting time prolonging, the moisture content of cheese incresc, and the fat content of cheese decreased. The cheese made by clotting 50min has better in springness, meltability and free oil release. The texture of this cheese was softer and smoother.更多还原