Study On Process And Maturity Of Feta Cheese From Milk Powder

In this paper, Feta cheese was made from fresh milk and whole milk powder, the processing technology and the physicochemical characteristics changes during the ripening process of Feta cheese was studied comparatively. The project included several parts such as:1.The formula and optimum technology were investigated by both single factor test. The results showed that the optimal technological parameters were that the addition amount of fermentation were 0.003%, the addition amount of rennet were 0.005%, the addition amount of calcium were 0.03%, salt concentration was 20%.2.With the analysis of process and results, the formula and optimum technology were investigated by both single factor and orthogonal test. The results showed that the optimal technological parameters were that Low-Heat treatment milk powder, the addition amount of fermentation were 0.003%, the addition amount of rennet were 0.005%, the addition amount of calcium were 0.03%, salt concentration was 20%.3.Through studying the value changes of Ph,pH 4.6-SN,12%TCA-SN under optimal technological conditions during cheese ripening, experiment results showed that the value of pH decreased in the first and second week, it decreased gradually to the end at the 14 day, but from the third week, it kept invariable lately. pH 4.6-SN of cheese increased gradually at first and subsequently raised slowly, while 12%TCA-SN of cheese increased continually. From these changes,we could see the optimum ripening time of Feta cheese was about 5 weeks. In the prior four weeks of maturity, pH value, Ph4.6-SN/TS content, 12% TCA-SN/TS were significantly different (P <0.05) between Feta cheese made from whole milk powder and fresh milk, after thirty days, the index was not significant (P> 0.05). Sensory value is always significant difference (P <0.05), but become close later. Comprehensive analysis, the best mature time of Feta cheese is about 5 weeks.4.Compared with fresh milk, Feta cheese made from whole milk powder have higher water content, higher yield, longer curd time, longer mixing time, curd strength is poor. The quality of Feta cheese can be improved by means of extending process time.