Application Of Mocur. And Geotrichum Penicillium In Camembert-type Cheese

This study was designed in order to develop the Camembert-type cheese, which has soft texture and warmer flavor, used by moulds from Chinese traditional food —— preserved beancurd and bean curd with odor.Mocur. and Geotrichum penicillatum (respectively named M1 and D1 in this paper) was chosen from six strains isolated from preserved beancurd and bean curd with odor. Milk was incubated with the two strains, and three types of Camembert-type was produced by the traditional method: Camembert-type cheese with M1(named CM cheese), and with D1 (named CD cheese) respectively and Camembert-type cheese with M1 and D1 (named CMD cheese). The ripened-time of three cheeses was determined. The effect of the different strains on textural and sensorial characterization of Camembert-type cheeses was investigated. Compared to Camembert cheese, the hardness, gumminess and chewiness of CM cheese were smaller, springiness was bigger and cohesiveness was not different significantly. The hardness, gumminess and chewiness of CD cheese were bigger. The hardness, gumminess, chewiness and springiness of CM cheese were smaller, and cohesiveness was bigger, which showed more mature and sofer texture. M1 could control "rancid" odor, and D1 was benefit for "sweet" odor. CMD cheese was characterized by a "sweet" and "salt" odor, a "buttery", "dairy" and "mushroom" flavor, had few " bitterness", "pungent" and "rancid" flavor.The chemical and physical changes in CMD cheese during ripening was studied further: 1, outer and inner pH value decreased till pH5.25 in the prophase of ripening, and then increased to about pH7.0; 2,The degree of proteolysis increased during ripening, but increased slowly from 12d to 20d of ripening time, and electrophoresis of casein hydrolysates showed the different patterns of proteolysis from Camembert cheese: it is easier for CMD cheese to proteolysis pre-κ-casein than Camembert cheese, and αs-casein and β-caein were hydrolyzesd to 50%~60%. 3,The content of total free fat acids (FFA) increased during ripening. The content of Stearic acid and Linolenic acid increased from 5d to 15d of the ripening time, Palmitic acid decreased, and long-chain FFAs were produced largely. The content of long-chain FFAs decreased and medium-chain FFAs increased from 15d to 27d of the ripening time. 4,The value of hardness, gumminess and chewiness decreased rapidly, springiness decreased also, and cohesiveness decreased placidly. 5,The volatile compounds changed during ripening. The content of organic acid increased firstly and then decreased. Alcohols was translated into other compounds during ripening, only 1-Octen-3-ol was produced from 20d to 27d of the ripening time. Methyl ketones were produced largely from 13d to 27d of the ripening time. There was not sulphur compoumds during ripening.