Process Optimization And Accelerated Ripening Of Minitype Hard Cheese

The processing of hard cheese is a complex process and optimizate the process can make the cheese processing process more standardized and controlled. Accelerating cheese ripening has a great economic value and broad application prospects. In this topic, firstly, used single factor and orthogonal experiment to optimizate the process technology of hard cheese; secondly, researched the effect of maturing temperature on its accelerated mature on the basis of optimum process technology; finally, researched the effects of adding lipase and high-pressure treatment on its accelerated ripening on the basis of optimum process technology and optimum temperature.By single factor and orthogonal experiments the technological process and the best process parameters of minitype hard cheese were determined:starter cultures adding amount was0.025g/L, CaCl2adding amount was0.015%, heat preservation mixing time was30min and fermentation pH value was6.4. The products accorded with the national standard of hard cheese.In the ripening of hard cheese raising temperature had no significant effects on the contents of moisture, fat, protein and texture characteristics, however, had significant effects on cheese pH, pH4.6-SN,12%TCA-SN, free fatty acid, free amino acid, structure, kind and of volatile flavor and sensory evaluation. The ripeness of cheese ripened at10℃for60days at or close to the cheese ripened at4℃for90days. Though ripened at20℃could accelerated cheese ripening, it resulted a decline in the quality of the cheese at the same time. So,10℃was the most suitable temperature for cheese ripeness.In the ripening of hard cheese added lipase had no significant effects on cheese moisture, protein, pH4.6-SN,12%TCA-SN, free amino acid and texture characteristics, however, had significant effects on cheese fat, pH, free fatty acid, structure, kind and of volatile flavor and sensory evaluation. The ripeness of cheese ripened at lipase level of0.04g/L for60days at or close to the cheese ripened at lipase level of0g/L for90days. So, the most suitable lipase level for elevating hard cheese ripening was0.04g lipase per litre milk.In the ripening of hard cheese high-pressure treatment had no significant effects on cheese moisture, fat, protein and texture characteristics; what’s more, had significant effects on cheese pH4.6-SN,12%TCA-SN, pH, free amino acid, structure and sensory evaluation; however, had adverse effects on cheese free fatty acid and volatile flavor when the high-pressure level exceeded a certain range. The ripeness of cheese at high-pressure of300MPa for60days at or close to the cheese at high-pressure level of0MPa for90days. Therefore, the most suitable high-pressure level for elevating hard cheese ripening was300MPa.