Wheat and Rice Bran as Natural Additives for the Protection of Fish Oil from Oxidation

Abstract

Fortification of food products with omega-3 polyunsaturated fatty acids (ω-3 PUFAs) is difficult due to their high oxidative susceptibility. Use of synthetic antioxidants in food products to extend shelf life is challenged by the growing demand for natural ingredients from consumers. In this study, the stabilization effect of wheat and rice bran on fish oil oxidation was investigated. Five, 10, and 20 g of fish oil were added to 95, 90, and 80 g of cereal brans, respectively. The obtained powders were homogenized and stored for accelerated oxidation study at 38 °C up to 30 days (to avoid dramatic changes of the oxidation reaction pathways compared to those at room temperature). Secondary oxidation products were analyzed by both solid phase microextraction-gas chromatography-mass spectrometry and liquid chromatography-high resolution mass spectroscopy. Wheat bran showed a better protection effect on fish oil oxidation. That could be explained by its phytochemical and physical stabilization effect. Heat and enzymatic treatments did not improve antioxidant capacity of wheat or rice bran. Fine wheat bran water extract protected the fish oil from oxidation to the same extent as the whole wheat bran.