Antioxidant properties of natural plant extracts containing polyphenolic compounds in cooked ground beef

Thiobarbituric acid-reactive substances (TBARS) values, hexanal content, and sensory analysis were used to evaluate the effectiveness of selected natural antioxidants to reduce warmed-over flavor (WOF) development in cooked ground beef. The control without added antioxidant showed the highest TBARS value, hexanal content, and WOF scores. Grape seed extract (ActiVin(TM)) and pine bark extract (Pycnogenol(R)) significantly improved the oxidative stability of cooked beef. Compared to the control, ActiVin(TM), Pycnogenol(R), and oleoresin rosemary reduced the hexanal content by 97%, 94% and 73% after 3 d of refrigerated storage, respectively. WOF scores showed a similar pattern as TBARS values and hexanal contents. TBARS values, WOF scores, and hexanal contents were all well correlated.