BIOCHEMICAL CHARACTERIZATION OF VEGETABLES WASTES AND DEVELOPMENT OF FUNCTIONAL BREAD

Abstract

The present study aimed at evaluating nutritional potential and antioxidant activity of the extracts derived from vegetable wastes such as carrot pomace, onion upper bulbs, and peels from garlic, tomato & potato. Proximate composition, minerals profiling and antioxidants activity as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) were estimated, and phenolics characterization was performed using high performance liquid chromatography (HPLC). Our results suggest that vegetable wastes such as peel and pomace, may be exploited as carriers of proteins, fiber, calcium, potassium, iron and zinc. Phenolics screening demonstrated presence of total hydroxybenzoic, hydroxylcinammic acids and catechin albeit anthocyanins and total flavonols were inadequately present in tomato pomace. Maximum total phenolics contents and DPPH activity were observed in HCl/MeOH extracts of tomato and garlic peels, respectively. Product development data suggest incorporating onion peel’s extracts in wheat flour to not elicit a significant change in bread composition.  Likewise, supplementation of onion peel powder (OPP) and extracts @ 6% and 1.5%, respectively improved color and textural properties of supplemented bread. Contextualizing the challenges of food insecurity and food industry waste management, our results confirmed that vegetable wastes, with improved nutritional profile and increased antioxidant potential, may be used for the preparation of value-added food products.