Nutrient Composition and Radical Scavenging Activities of Watermelon Seed-based Nutribar

Aims: The present study is aimed to develop watermelon seed nutribars (WMSNB) and to determine proximate content, antioxidant activity, free fatty composition and also sensory evaluation in order to create awareness of its potential nutritional values and increase its consumption in the form of nutraceuticals, functional foods and pharmaceuticals.

Study Design: Proximate analysis, total phenolic, antioxidant activity and free fatty acid profile was carried by using well established in-vitro assay.

Place and Duration of the Study: Department of Clinical Nutrition and Dietetics, Sri Devaraj Urs Academy of Higher Education and Research. Kolar, between June 2021 and November 2021

Methodology: The developed nutribars samples were evaluated for proximate analysis (moisture, crude protein, ash, total fat, crude fibre, and total carbohydrate), total phenolic, antioxidant activity by using DPPH assay, free fatty composition by using GC-MS, and sensory characteristics based on hedonic scale point. The ingredients used for preparation of WMSNB were Watermelon seeds (100gm), jaggery (50gm), coconut flakes (15gm), sesame seeds (10gm) and ghee (5gm). Peanut nutribars (PNB) were also developed by replacing Watermelon seeds (WMS) with peanuts which was used for comparison purpose.

Results: The proximate screening indicated that protein (15.72%) and carbohydrate content (52.49%) was high in WMSNB compared to PNB. The prepared WMSNB showed rich in phenolics and also possessed good antioxidant activity against DPPH. The free fatty acid composition showed that linolenic acid, stearic acid and lauric acid of oil extracted from WMSNB were 51.15%, 10.65% and 6.49% respectively, while oleic and palmitic acid extracted from PNB were 38.11% and 14.62% respectively. The overall sensory evaluation showed that there was no significant difference (P<0.05) between WMSNB and PNB.

Conclusion: The antioxidant capacity of the WMSNB constituent underlines the potential source of natural antioxidants and bioactive compounds for the therapeutic purposes.