Isolation Of Lactic Acid Bacteria From Xin Jiang Fresh Cheese And The Studies Of Property

Xinjiang natural fermentation fresh cheese contains a rich microbial resourceswhich giving the unique flavor of dairy products after thousands of years ofdomestication.The main microorganisms were isolated in this artical, and then wehave the initial screening of these strains in milk curd.The strains were rescreenedfrom some fermentation property, such as speed of acid production, producting stricky,producing fragrance, proteolysis and lipolysis capacity and combine these high-quality strains, which find out excellent starter with the purpose of making cheese.The purpose of this artical is providing primary foundation of developing and makingcheese.These main strains were isolated with MRS, M17and PDA medium.The resultsof isolation is22strains available that include16lactobacillus and6lactococcus.Wemeasure22strains acid production, stricky production, fragrance production, thecontent of diacetyl, proteolysis and lipolysis capacity and evaluate textural propertiy,and finally these strains were isolated that have different excellent fermentationproperties.The results of screening show that strains which have the fastest productionof acid is C63M and C34M. The higher productionof stricky is C63M, C34M andC61-2M. The higher content of diacetyl is C34M and C103M, their diacetyl amountis7.47±0.01μg/m and6.62±0.01μg/mL.C104and C61-2M have higher proteolysiscapacity, thier free amino acid is469.42mg·L-1and390.68mg·L-1, the5strains hardlyhave lipolysis capacity and have great textural properties.According to these strain individual great fermentation, starter is mixed andcalculate fermentation propertis of mixed strains again like above.Finally one group isseleced as fermentation to produce cheese.After identification, they are lactobacilluscasei, lactobacillus paracasei ssp paracasei, lactobacillus rhamnosus and Lactobacilluszeae.2%,3%,5%starter were used to produce cheese, and then their moisture andcheese yield were claculated. At the same time, we also evaculate cheese quality andcalculate their textural properties. The results show that cheese have the fastest yieldwith5%fermentation, and the amount is56.79%, while cheese moisture, testuralproperty and its sensory evaluation are also great.