effects of green tea, echinacea and rosemary extracts on shelf life of broiler thigh meat

the effect of green tea, echinacea purpurea, rosemary extracts on dilation of oxidation and rancidity development in broiler thigh meat was studied. therefore, fresh thighs were dipped in 0.1%  alcoholic aqueous extract during 15 min and kept frozen (-20°c) until 6 months. sampling was carried out at 1, 30, 60, 90, 120,150 and 180 days of aging at -20°c. a parallel experiment with ascorbic acid as an antioxidant supplement and distilled water (control) was carried out in the same condition. green tea extract had the most effective antioxidant activity and echinacea and rosemary were as second and third antioxidants activity in comparison to ascorbic acid and control respectively (p<0.05). samples treated with green tea, rosemary and echinacea had higher redness rather than control and samples treated with ascorbic acid (p<0.05).  a significant decreased in lightness was observed on 30th and 90th days of aging times (p<0.05). no significant differences were observed between different treatments on leg meat water holding capacity. the mean ph of thigh meat were 6.25 to 6.36 in different treatments and aging times, the highest ph value belonged to echinacea treatment (ph=6.36) and the lowest was observed in control treatment (ph=6.28) (p<0.05). finally, results showed that green tea, echinacea and rosemary are powerful and effective antioxidants when dipping broiler thigh meat in soluble extract of there.