Evaluation of the antioxidant potential of natural food/plant extracts as compared with synthetic antioxidants and vitamin E in raw and cooked pork patties

Antioxidant potential for previously identified optimum levels of aloe vera (AV), fenugreek (FGK), ginseng (G), mustard (M), rosemary (R), sage (S), s oya protein (SPI), tea catechins (TC) and whey protein concentrate (WPC) we re evaluated in raw and cooked patties manufactured from frozen pork. The o ptimum levels determined were: AV (0.25%), FGK (0.01%), G (0.25%), M (0.10% ), R (0.10%), S (0.05%), SPI (0.10%), TC (0.25%) and WPC (4%). Test ingredi ents were evaluated against synthetic antioxidants butylated hydroxyanisole /butylated hydroxytoluene (BHA/BHT) (0.01%) and a supplemented meat contain ing natural antioxidant, alpha -tocopherol (1000 mg alpha -tocopheryl aceta te/kg feed). Ranking the decreasing antioxidant effectiveness of added ingr edients in raw patties on day 9 showed that: Control > G > SPT > FGK > AV > M > WPC > S > alpha -tocopherol > R > TC > BHA/ BHT. Cooking resulted in a four-fold increase in TEARS values over raw patties with TC being the most effective antioxidant having significantly (P < 0.001) lower TEARS values than the cooked control on days 3, 6 and 9. Ranking of decreasing antioxida nt effectiveness of added ingredients showed that: M > SPI > G > FGK > alph a -tocopherol > AV > control > S > BHA/BHT > R > WPC > TC. BHA/BHT had the most beneficial effect on cooked meat redness with Hunter 'a' values being significantly (P < 0.05) higher than the control on days 3, 6 and 9. Rankin g of Hunter 'a' values for added test ingredients showed that FGK > WPC > c ontrol > R > BHA/BHT > alpha -tocopherol > TC > AV > SPI > M > G > S on day 9. Hunter 'L' and 'b' values showed no significant trend over the storage period in either raw or cooked patties. The pH values of both raw and cooke d pork control patties and products containing added test antioxidants were variable and while a number of trends were observed, no significant differ ences were recorded between samples, (C) 2001 Elsevier Science Ltd. All rig hts reserved.