UTILIZATION OF NATURAL ANTIOXIDANT EXTRACTS OF POMEGRANATE PEELS AND GUAVA SEEDS IN VEGETABLE OILS STABILITY

Waste management is one of the most modern important trends in food technology to overcome the problems related to its accumulation, and in the same time to maximize its economical value. Pomegranate peels and guava seeds are resulted from food industry in big quantities, so this work is a tempt of utilization of these wastes as sources of natural antioxidants, which could be used in food industry. Ethanolic extracts of both pomegranate peels and guava seeds, separately, with different concentrations (300 ppm, 600 ppm and 900 ppm), were examined for their antioxidant activity when added as well as BHT (200 ppm) to preheated RBD soybean and sunflower oils, separately, comparing to control samples (without any addition). Peroxide value, UV absorbency (K232 and K270), Free fatty acids and the changes in fatty acids composition as parameters for evaluation of stabilization efficacy of the ethanolic extracts of pomegranate peels and guava seeds on both soybean and sunflower oils in accelerated conditions (Schaal oven test). The obtained results showed that, each of pomegranate peel extractsand guava seeds extracts with 600 and 900 ppm have higher antioxidant effects than that of BHT (200 ppm), while 300 ppm extract concentration has lower antioxidant effect than BHT. These results showed the possibility of using these wastes in retarding the oxidation of vegetable oils in industrial scale.