Effect of conventional cooking methods on lipid oxidation indices in lamb meat

Lipid oxidation is one of the most deteriorative reactions occurred in foodstuff which has harmful impacts on the both food quality and consumer's health. This study was designed to speculate the influence of three conventional cooking methods including boiling, frying and grilling on lipid oxidation parameters in cooked lamb meat. Sections of lamb meat from longissimus dorsi muscle, taken from native Lori-Bakhtiary sheep species were cut into uniform pieces and cooked using boiling, frying and roasting methods according to the cooking routine and tradition in Iranian society, in terms of temperature and time. Proximate compositions (moisture, lipid, ash and protein) in the raw and cooked meat were determined using the standard methods of analysis. Moreover, weight loss was measured after each treatment. Lipid oxidation parameters such as peroxide value, conjugated diene and TBARS indices were measured in the raw and cooked samples. Evaluation of lipid oxidation parameters showed that peroxide value was significantly decreased in all cooked samples. In contrast, conjugated diene value was significantly increased in the fried and grilled samples (p<0.05) while, boiling for 90 min was resulted in significant increase in TBARS number (p<0.05). Although compared to the other methods, lower temperature was applied in the boiling process; higher level of lipid oxidation was developed. This might be due to the longer cooking duration in boiling method. Therefore, in the future studies, reduction of boiling duration should be further assessed considering the microbial and nutritional point of views.