The effect of dietary fat, vitamin E and selenium concentrations on the fatty acid profile and oxidative stability of frozen stored broiler meat

A total of 160 Ross 308 female broilers from day 22 to 35 of age were used to investigate the effects of vitamin E and selenium (Se) supplementation on performance, fatty acid profile and oxidative stability of meat enriched with n-3 fatty acids. There were 4 treatment groups, 3 diets contained rape seeds and fish oil (60 and 15 g.kg(-1), respectively - RF), the control diet contained animal fat - lard. To the RF diet different doses of vitamin E and Se were added (80 and 0.3, 150 and 0.3, 150 and 0.7 mg per kilogram of diet, respectively). Performance was measured and samples of breast and thigh meat were vacuum packed and stored at -30 degrees C. The concentration of thiobarbituric acid reactive substances (TBARS) was determined after 3 weeks and after 3 months of frozen storage, when also fatty acid profiles, vitamin E and cholesterol contents in meat were measured. Body weight gain and feed conversion ratio were negatively influenced (P <= 0.05) by the increased dietary level of Se. Feeding diets with rape seeds and fish oil resulted in higher concentrations and lower n-6/n-3 PUFA ratios in breast and thigh meat (P <= 0.05) compared with the control. The increase of dietary vitamin E, but not Se, increased the tocopherol content in meat and reduced TBARS values in 3-month-stored thigh meat (P <= 0.05). It may be concluded that fortification of diets with vitamin E increases its concentration in, and oxidative stability of frozen stored breast and thigh meat, but no additional benefit was observed in feeding excess Se in combination with vitamin E.