Lipid and protein antioxidant capacity of dried Agaricus bisporus in salted cooked ground beef

Dried Agaricus bisporus powder (DAB)'s antioxidant capacity was tested in refrigerated cooked ground beef (CGB) containing 0, 1 or 1.5% NaCl. Lipid and protein oxidation products were monitored over time and correlated with changes in phenolic content. On day 16, 88-94% lower malondialdehyde (MDA) was found in CGB with DAB compared to control (1.15 mg MDA/kg samples). Volatile aldehydes were up to 99% lower on day 16 in CGB with DAB than controls. In unsalted CGB, thiols dropped by 82% in control compared to < 60% in CGB with DAB. On day 16, tryptophan fluorescence decline in unsalted control was higher (28%) than that in CGB with rosemary or DAB (2.4-5.5%) while Schiff bases declined in control and CGB + 1% DAB, but increased in CGB + 2% and 4% DAB. DAB's extension of shelf life was concentration dependent. Phenolic compounds had moderate to strong negative correlations with MDA up to day 10 indicating a possible role of DAB phenolics in preventing malondialdehyde production.