Quality matrix reveals the potential of Chak-hao as a nutritional supplement: a comparative study of matrix components, antioxidants and physicochemical attributes

Abstract

In the current trend of increased health consciousness in response to increased incidence of lifestyle disorders, functional foods, and nutritional supplements got immense acceptance globally. Whole grain foods rich in functional bio-actives being a better substitute for supplements, there is an emerged interest in exploring potential candidates like pigmented rice. The present study thus aims to evaluate the natural variability in matrix composition owing nutritional and antioxidant potential of pigmented niche rice varieties like Matta (red) and Chak-hao (black) compared to non-pigmented (NJ 72 and PB 1509). Comprehensive NQM developed indicated that Chak-hao, geographical indication (GI) rice has stout nutritional makeup in terms of phenolics (2.5 mg/g GAE), anthocyanins (0.65 g/kg), proanthocyanidins (54 mg/100 g), antioxidant activity (36 µmol TE/g) and resistant starch (4.13%) compared to Matta. The content of high-quality fatty acids like oleic (38.8%), linoleic (29%), and anthocyanin forms like cyanidin-3-glucoside (C3G)- 304 mg/Kg, delphinidin-3-glucoside (D3G)- 220 mg/Kg and peonidin-3-glucoside (P3G)- 120 mg/Kg was also most expressive in the black pigmented rice Chak-hao. Highly significant (p < 0.05) antioxidant activity and positive correlation with total phenolics, anthocyanins and proanthocyanidins content were most evident in pigmented varieties. Physicochemical attributes endorsing cooking time, water uptake ratio, grain elongation ratio, gruel solid loss and swelling ratio varied between 15–35 min, 2.17–3.2, 1.5–2.3, 0.28–1.25 and 1.75–2.66 respectively. The correlation between nutritional attributes endorsing antioxidant potential being strongly positive and most significant for Chak-hao, it could be the stellar addition for functional food industry as a nutritional supplement for addressing the ever-increasing pandemics like diabetes, obesity and other chronic diseases.