Comparative Evaluation of Antioxidant Potential in Thermally Processed, Underutilized Food Grains of the Himalayan Region

Abstract

Aims: To determine the bioactive components and total antioxidant capacity (TAC) in selected underutilized crops of the Himalayan region viz. Barnyard millet, Grain amaranth, Rice bean, Black soybean and Horsegram. Study Design: Experimental design (Lab experiment). Place and Duration of Study: Department of Foods and Nutrition, College of Home Science, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, in the year 2016-18. Methodology: We applied different processing techniques (covered pan cooking and pressure cooking) in the underutilized crops and analyzed the total phenol, total flavonoids and total antioxidant capacity (Ferric reducing antioxidant power (FRAP) assay and (2, 2-Diphenyl-1-picrylhydrazyl) (DPPH) by using standard methods. Results: It was found that black soybean had highest phenolic content after both thermal treatments (3233.76 mg GAE/100 g for pan cooked and 1883.11 mg GAE/100 g for pressure cooked samples) and TAC by both FRAP (6423.76 mg TE/100 g for pan-cooked and 4415.58 mg TE/100 g for pressure cooked) and DPPH (536.41 and 453.98 mg TE/100g for pan and pressure cooked samples, respectively) method. Among raw samples, rice bean contained the highest flavonoid content and TAC by FRAP assay. In contrast, raw grain Amaranth showed the lowest phenolic content. Further, pressure cooking was found to be better for barnyard millet, while in pulses, pan cooking yielded the best results (in terms of increased value/lower losses). Conclusion: It can be concluded that among pulses pan cooked black soybean was found to have a good store of bioactive compounds as compared to rice bean and horse gram. The pressure cooking method was found to be suitable for millet like a barnyard.