Effect of rosemary and thyme extracts on the fatty acid profile, lipid oxidation, quality and some fat health related indices of chicken burger

The current study aimed to include natural ingredients (rosemary and thyme extracts, as well as a combination of them) in the formulation of chicken burgers in an attempt to improve their fatty acid profile, lipid oxidation, quality and some fat health related indices. Four batches of chicken burgers were manufactured: product 1: control burger, product 2: burger fortified with rosemary extract, product 3: burger fortified with thyme extract, product 4: burger fortified with rosemary and thyme extracts. The samples were analyzed for their chemical characteristics (moisture, ash, fat, protein, and carbohydrates), fatty acid profile, thiobarbituric acid reactive substances (TBARS) to determine lipid oxidation, and nutritional quality of chicken burger by calculating the atherogenic and thrombogenic indices, polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) ratio, and omega-6 / Omega-3 (ω 6/ω 3) fatty acid ratio. The results showed that the incorporation of extracts in the chicken burger caused a significant decrease in the percentage of trans-fat from 0.06 to 0.02 and atherogenic (AI) and thrombogenic (IT) indices from 0.30 to 0.26 and from 0.79 to 0.72, respectively. A non-significant decrease in saturated fatty acid (SFA) from 27.33 to 27.23was noted. However, a significant increase in the levels of polyunsaturated fatty acid (PUFA) from 15.36 to 19.67, monounsaturated fatty acid (MUFA) from 47.28 to 48.88, ω 6/ω 3 ratio from 13.49 to 15.85, and PUFA/SFA ratio from 0.56 to 0.72 in chicken burger was observed. Whereas addition of the extracts had a variable influence on the sensory characteristics of the freshly prepared and stored burgers. It was concluded that the fortification of chicken burger with rosemary and thyme extracts improved the nutritional and quality properties and gives a desirable change in sensory evaluation. Key words: Rosemary extract, Thyme extract, Fatty acid profile, Health indices