Abstract

This study evaluated the effect of the dietary inclusion of Quillaja polyphenols on the antioxidant status of the animal and the oxidative quality of meat. One hundred and twenty-eight broiler chickens were assigned to the following experimental groups, T0: basal diet (control), T1: 500 mg/kg of extract 1 + basal diet, T2: 1000 mg/kg of extract 1 + basal diet, T3: 2000 mg/kg of extract 1 + basal diet, T4: 500 mg/kg of extract 2 + basal diet, T5: 1000 mg/kg of extract 2 + basal diet, T6: 2000 mg/kg of extract 2 + basal diet, and T7: 100 mg/kg of a-tocopherol (Vit E) + basal diet. Quillaja extract 1 was composed by 10% of extracts soluble in water, with 90% of particles smaller than an 80-mesh sieve, without additives. Quillaja extract 2 was composed by 8% total phenols, 2% of tannins and 0.2% of saponins. The animals were slaughtered on d 42 and samples of intra-cardiac blood and tissue samples (liver, breast and thigh) were taken and assigned to treatments of 0, 2, 4 and 6 d of refrigeration. Feed conversion and FRAP (Ferric Reducing Ability of Plasma) index were not affected by treatments. Compared with extract 1 treatments, control had higher lipid oxidation in liver (basal and induced oxidation) and thigh (induced and induced with Fe). Compared to extract 2 treatments, control induced higher lipid oxidation + Fe. Overall, the Quillay polyphenol extracts had the same protective effects against lipid oxidation as compared to those from Vit E group in broiler thigh tissue. This study is important for those producers looking to ameliorate lipid oxidation problems in meat.