Nutritional and bioactive compounds in dried tomato processing waste

Abstract

This research investigated the nutritional and antioxidant composition of tomato processing waste with the aim to enable the development of new alternatives for the recycling of this by-product. The samples of dried tomato waste were found to contain 176.2 g/kg protein, 21.9 g/kg fat, 524.4 g/kg crude fiber and 42.1 g/kg ash. The essential amino acids represented 34.2% of total protein, the most abundant being leucine, followed by lysine and isoleucine. Unsaturated fatty acids represent 77.04% of the total fatty acids, linoleic being the major one. The results confirmed that dried tomato wastes contain considerable amounts of lycopene (510.6 mg/kg) and β-carotene (95.6 mg/kg) and exhibited good antioxidant properties. Total phenolics showed average contents of 1229.5 mg GAE/kg, of which flavonoids accounted for 415.3 mg QE/kg. Ellagic and chlorogenic acids were the most abundant phenolic acids while among flavonoids only rutin and myricetin were quantified.