Valorization of bioactive profile and antioxidant properties of Kinnow peel, and pulp residue: a step towards utilization of Kinnow waste for biscuit preparation

Fecha de publicación: 01/02/2023
Fuente: Citrus Byproducts Extraction
Abstract
Huge amount of waste (peel and pulp residue) are generated whenever fruits are processed at industrial scale. Pulp residue and peel are generally discarded as waste, which could be a good source of antioxidants and fibers. Present work was performed by keeping in the view the importance of secondary metabolites and fiber content present in Kinnow peel and pulp residue. Five different extraction medium [methanol (50%), methanol, water, ethanol and ethanol (50%)] was used for the purpose to extract bioactive metabolites from Kinnow peel and pulp residue. As compared to pulp residue (24.73 mg GAE/g), Kinnow peel showed the presence of higher phenolic compounds (36.68 mg GAE/g). Positive correlation between bioactive metabolites and antioxidant properties was observed. Among selected solvents methanol (50%) was observed as efficient extraction phase followed by ethanol (50%), water, methanol and ethanol. HPLC analysis indicates the presence of ascorbic acid, catechin, gallic acid, catechol, resorcinol, vanillin and quercetin in studied extracts (peel and pulp residue). Further, Kinnow peel and pulp residue (2–10%) was used in the preparation of fortified wheat biscuits. Addition of Kinnow peel and pulp residue significantly enhance the flavor of biscuits. Overall acceptability score represents that biscuits prepared using peel powder were acceptable at 2–6% peel concentration however biscuits having pulp residue were acceptable at 2–8%. Easy availability, low cost and eco-friendly nature of Kinnow peel and pulp residue makes it a good experimental material for the preparation of cost effective antioxidant and fiber rich bakery products and dietary supplements. Further, the use of Kinnow waste could generates extra income for the fruit processing industries.

Graphical abstract