Research and Development on Cheese Powder Directly Made from Liquid Milk Hydrolysis

Cheese powder is a kind of nutritional food stuff and flavoring, widely used in food industry. In this paper, mold cheese powder directly made from liquid milk was studied, in which mold and enzymes hydrolysis were combined to speed up the formation of flavor compounds and shorten the production period. In this research, the strains of Actinomucor elegans, Penicillium camemberti and Penicillium roqueforti were investigated to ferment the milk, among which the strain of Actinomucor elegans was indicated to be most effective according to the result of FFA% and FAA% produced in fermentation, which reached 4.28% and 0.37%, respective, when inoculated at the concentration of 1.94×106 cfu/mL and fermented at 29 °C for 4 days. In order to accelerate the flavor formation, the effects of lipase and protease combined hydrolysis was subsequently studied. Through orthogonal experiments, the lipase zymolysis process was confirmed as addition of 2.0%(w/v) lipase and 12%(w/v) fat and kept at 50 °C for 6h, and then added protease 0.15%(w/v) and protein 6%(w/v), at 55 °C for 8h. The spray-drying was carried out at the inlet and outlet temperature of 180-190 °C; and 80-90 °C, respectively, and the input material speed was controlled at the speed of 30mL/min under the pressure of 35Mpa to protect the volatile composition. The main components of the cheese powder were determined as water 9.71%, fat 29.21% and protein 27.23%. By SPME &GC-MS analysis, the dominant flavor substance of the product was known as ethyl tridecanoate 18.57%, decenoic acid ethyl ester 16.92%, n-decanoic acid 8.470%, tetradecanoic acid ethyl ester 8.457%.