EFFECT OF COOKING AND STORAGE ON LIPID OXIDATION AND DEVELOPMENT OF CHOLESTEROL OXIDATION-PRODUCTS IN WATER-BUFFALO MEAT

Buffalo meat was subjected to two cooking methods viz. broiling and pr essure cooking and two storage procedures viz. refrigerated (4 degrees C) storage for six days and frozen (-10 degrees C) storage for 90 day s. Changes in lipid oxidation and development of cholesterol oxidation products were studied in raw as well as cooked meal samples. Total li pid, phospholipid, cholesterol, free fatty acid, glycolipid and glycer ide contents increased significantly, on cooking of meat but did not s how any significant changes during either refrigerated or frozen stora ge except for free fatty acid content which showed an increase. The TE A values also increased during storage but not to the extent of indica ting rancidity. Cholesterol oxidation products separated by thin layer chromatography were: cholestanetriol, 7-alpha-hydroxycholesterol, 19- hydroxycholesterol, 7-ketocholesterol, cholesterol-alpha-epoxide, chol esterol-beta-epoxide and an unidentified fraction. All these fractions , except for the unidentified fraction, increased on cooking and stora ge. The cholesterol-beta-epoxide fraction was resistant to changes. Ch anges in broiled meat were more pronounced compared to pressure cooked meat. Frozen storage did not prevent the development of cholesterol o xidation products in buffalo meat. Copyright (C) 1996 Elsevier Science Ltd