Lipid and protein oxidation is a major phenomenon reducing meat quality during cooking and storage and leading to off-flavour formation and rancidity. The use of vegetable extracts to increase shelf life is a promising new frontier in the prevention of oxidation. In this study the efficacy on lipid and protein oxidation was evaluated in chicken meat mixed with conventional methanol/water and supercritical extracts of Echinacea angustifolia after cooking and at different times of cold storage in order to propose these matrices as natural substances to increase the shelf-life of meat products. Echinacea spp. are native to North America and were traditionally used by the Indian tribes for a variety of diseases, including mouth sores, colds and snakebites. The three most commonly used Echinacea spp. are Echinacea angustifolia, Echinacea pallida and Echinacea purpurea. In particular, a series of experiments have shown that E. angustifolia extracts have significant immunomodulatory activities. Total phenols and antioxidant activity of the SFE extracts were used as parameters to characterize the vegetable extracts, TBARS and MDA were considered to monitor lipid oxidation, while protein oxidation was measured as carbonyl compounds. Results show a protective action of plant antioxidants against oxidation, but also a greater selectivity and a higher efficiency of natural extracts obtained by SFE respect to conventional extract. The study of the metabolic profile was performed by tandem mass spectrometry (LC/MS/MS). (C) 2012 Elsevier B.V. All rights reserved.