Effects of ripening temperature on the kinetics of proteolysis in Lighvan cheese

Cheese ripening is one of the most impotant stages during cheese production. After milk coagulation, in order to achieve the appropriate organoleptic properties, it should be exposure to the suitable environmental conditions. Proteolysis is the most substantial stage during cheese ripening. Several parameters are effected the proteolysis in cheese production process such as temperature, salt concentration, water activity and the amount of retentate coagulant enzymes in curd. The goal of present study was to investigate effect of temperature (4, 8, 12ºC) and salt concentration (8, 10, 12%) on kinetic of proteolysis during two monthes. Samples were exposed to physicochemical experiments each two weeks. In order to investigate kinetic reactions, the amounts of soluble nitrogen in pH= 4/6, non protein nitrogen, color intensity of α-casein and β-casein taint in Urea poly acryl-amide gel electrophoresis were measured. By increasing the temperature, degradiation of α-casein and β-casein and production of soluble nitrogen in pH= 4/6, and non protein nitrogen were intensified. Results are also showed that, rising the temperature in constant salt concentration, leads to increase the kinetic constant, whilst the calculated amounts of kinetic constant at 12ºC for all of parameters were the highest. By investigation of proteolysis kinetic in cheese and reciprocal effects of temperature and time, optimum ripening conditions were detrmined at 8 ºC and 10% salt concentration for 6 weeks to obtainig the product with suitable organoleptic properties and high quality.