Armenteros, Monica;Morcuende, David;Ventanas, Sonia;Estevez, Mario

Univ Extremadura, Caceres 10003, Spain

fruit phenolics;protein oxidation;lipid oxidation;nitrite;ascorbate

The effect of the addition of natural antioxidants from strawberry tree (Arbutus unedo L.; AU) and dog rose (Rosa canina L.; RC), in frankfurters elaborated with or without the addition of antioxidant additives (sodium ascorbate and nitrite) was studied. Six different types of experimental frankfurters were prepared depending on the addition of phenolic-rich extracts from RC and AU and the presence (P) or absence (C) of antioxidant additives. Thiobarbituric acid reactive substances (TBARS)-numbers significantly increased during chilled storage of C-frankfurters while additives and fruit phenolics inhibited lipid oxidation in P-frankfurters. The amount of protein carbonyls significantly increased in all treatments except in P-AU frankfurters. The discoloration process that occurred during the chilled storage was reduced by the addition of substances with proven antioxidant activity (P-frankfurters). Texture characteristics as hardness, springiness, cohesiveness and gumminess also suffered a significant deterioration in C-frankfurters. The use of phenolic fruit extracts in combination with traditional antioxidant additives is a successful strategy to enhance the oxidative stability of frankfurters without modifying their color and texture properties.