OBTAINING ANTIOXIDANTS FROM FOOD INDUSTRY WASTE AND THEIR USE IN FATS

Abstract

The food industry generates a large amount of waste and by-products of processing, which becomes a problem for the environment. Potato and onion peel, tomato seeds and peel are agro-industrial wastes of the world's main vegetable crops. However, the potential for antioxidants from them is not yet fully known. In this work, the influence of extracts obtained from these wastes on the process of inhibition of the rate of oxidation of sunflower oil was studied. Regression equations describing the process of extraction of biologically active substances from crop production waste as a result of water-ethanol extraction at a temperature of 60°C were obtained. It was established that the optimum concentration of ethanol in the water-ethanol mixture of extractants is in the range of 70–80%. Increasing the extraction time has a positive effect on the yield of extractive substances (at an interval of 2–15 hours). The kinetics of oxidation of sunflower oil by the accelerated method was studied and the antioxidant activity of the obtained antioxidants was determined, which is: for onion peel 2.29 (ie at a concentration of antioxidant 200 mg/kg oil the induction period of sunflower oil oxidation is more than doubled). For potato peels, this figure is 3.17, and for tomato peels – 1.85. All antioxidants obtained from plant waste were no less effective than butylhydroxyanisole (antioxidant activity – 1.93). The effectiveness of antioxidants varied as follows: onion peel > potato peel > butylhydroxyanisole > tomato residues. The expediency of using ascorbic acid in the course of water-alcohol extraction of antioxidants from vegetable raw materials has been proven. It has a positive effect on increasing the output of antioxidants and on extending the induction period of sunflower oil as a result of its own antioxidant properties. The existence of a synergistic effect between ascorbic acid and substances extracted from potato, onion and tomato peel has been proven, which in numerical value is 163, 126, and 180%, respectively.