Antioxidant effects of rosemary extract and whey powder on the oxidative stability of wiener sausages during 10 months frozen storage.

Twelve (Large White×Landrace) gilts were randomly allotted in a 2×2 factorial design with the respective factors being dietary vitamin E (10 or 200 mg/kg feed) and dietary fishmeal (0 or 5%). Wiener sausages were manufactured with or without antioxidants such as rosemary extract and sweet whey powder from meat obtained from the animals after slaughter and stored for 5 days at 4 °C. The oxidative stability of the wieners was examined over ten months of frozen storage. Lipid oxidation in the product was measured by means of thiobarbituric acid reactive substances (TBARS) and fluorescence shift. Sensory evaluation of the product to detect oxidative changes was also carried out. The fluorescence shift method was unsatisfactory in the case of wieners containing rosemary extract, as it appeared that the extract contained compounds that fluoresced and therefore interfered with the method. No lipid oxidation as measured by TBARS, fluorescence shift and sensory analysis was observed in wieners stored at -20 °C for 10 months. The oxidative stability of wieners was unaffected (P>0.05) by dietary treatments or by the addition of antioxidants. The high oxidative stability of the wieners, even in the absence of antioxidants, could be due to sodium erythorbate present in the formulation as an additional antioxidant.