UTILIZATION OF PEACH AND TOMATO WASTES AS UNCONVENTIONAL SOURCES OF EDIBLE OILS AND NATURAL ANTIOXIDANTS

Abstract

Recycling some waste materials especially, peach and tomato seeds to beneficial materials with high nutritional and functional properties as well as, unconventional sources of edible oils with highly antioxidative properties was the main target of this study. The obtained results revealed that peach seeds had the highest content of oil (43.5 %), and the chemical properties were in the normal range of edible oils. The percentage of the unsaturated fatty acids of peach and tomato seeds oils were high (92.677 and 83.370 %, respectively) especially , essential fatty acids ( Unoleic , Omega 6 ), which reflects good nutritional value of these oils. The oxidative stability of sunflower oil increased with increasing the levels of peach methanolic extract up to 400 ppm that exhibited the best oxidative stability and prolonged the shelf life of sunflower oil to 12.5 months. The highest oxidative stability ( 8.84 hr.) was obtained using tomato methanolic extract at level of 600 ppm compared with those obtained with other levels . Shelf life and antioxidant activity of sunflower oil increased gradually with increasing the tomato methanolic extract levels (11.03 to 12.67 hrs and 1.02 to 1.18, respectively). Furthermore, lycopene crude extract acted as pro-oxidant in higher levels, meanwhile, lower levels of lycopene extract (20 and 40 ppm) had an antioxidant effects on the stability of sunflower oil. From the obtained results, it could be concluded that peach and tomato seeds are considered rich sources of edible oils and natural antioxidants that play a great role in protecting human body. Utilization of these wastes will improve the environmental ecology of industry by recycling its by-products and decrease the problems of pollution from industrial wastes .