The oxidative stability of cooked chicken breast burgers from chickens reared on organic (n=3), free-range (n=3), and conventional (n=3) diets was determined. α-Tocopherol and fatty acid concentrations were also determined. Organic, free-range and conventional chicken breasts were obtained from local retail outlets. Significant (P<0.05) differences in α-tocopherol concentrations were found between samples indicating that α-tocopherol concentrations were dependant on the individual source diet rather than whether the sample was of organic, free-range or conventional origin. Concentrations of fatty acids also appeared to be dependent on individual source diets. Compared with other samples, the three organic samples and one free-range sample had lower concentrations of monounsaturated and polyunsaturated fatty acids of n-3 and n-6 series. Burgers were manufactured, cooked and stored in a modified atmosphere (20% CO2: 80% N2), held at 4 oC under fluorescent light and oxidation monitored on days 1, 3, 5 and 7. Significant (P<0.05) differences were found in lipid oxidation (monitored by malondialdehyde thiobarbituric acid (MDA-TBA) values) between samples on days 1, 3, 5 and 7 of refrigerated storage. α-Tocopherol concentration and MDA-TBA values appeared to be related in most samples. In general, MDA-TBA values were in the following order throughout the selected storage period: organic>free-range>conventional. It was concluded that cooked breast burgers from broilers fed organic diets had a lower shelf-life (oxidative) stability compared with cooked breast burgers from broilers free-range and conventional diets. Stability, in the present work, appeared to be related more to α-tocopherol concentration than to fatty acids.
How to cite this article
J.B. Lawlor, E.M. Sheehan, C.M. Delahunty, P.A. Morrissey and J.P. Kerry, 2003. Oxidative Stability of Cooked Chicken Breast Burgers Obtained from Organic, Free-range and Conventionally Reared Animals. International Journal of Poultry Science, 2: 398-403.