ABSTRACT
Domiati cheese is the most popular soft cheese in Egypt, it is consumed fresh or after ripening in salted whey up to 5-12 months. The Keeping quality of Domiati cheese - fat extends for several months if Domiati cheese produced mm der proper conditions The development of rancid and/or oxidized flavour as a result of lipolytic and oxidative deterioration, is usually undesirable and deracts from their market value, and creats problem to shelf life. Organoleptically, rancid and/or oxidized taste is though to be masked and in Domiati cheese, due to its higher salt content and proteolysis. Therefore. this study dealt with detailed quantitative analysis to throw some light on ripened Domiati cheese-fat deterioration - A total of 11 brands of filmed cans-pickled Domiati cheese made from raw milk of different ripening periods, representing 11 different creameries, distributed in 7 provinces, were collected from Giza super markets, prepared and analyzed as obtained to assess their rancid and oxidative fat - deterioration, and to the presence of some important catalytic agents for autoxidation; and some factors that slowdown or enhance rancid deterioration. The obtained results shows the following: 1- All tested Domiati cheese - brands, made from raw milk, show comparatively much higher rancid and oxidized deterioration as reflected in certain chemical values as those of peroxide value [mEqo2/kg fat]; acid degree value; acid value as FFA [% m/m as oleic acid] and free fatty acids composition. 2- 90.91% of cheese brands contain much higher copper levels [0.14-0.45 mg/kg], which represent 233-75-fold than that required for autoxidation [0.06 rng / kg] whereas 80% of samples contain higher iron levels [21.3 - 42.9 mg / kg] than that specified for canned foods [