Characterisation of the α-GOS profile of field pea and cowpea cultivars and their modulation through sustainable processing methods

Kalpana Tewari^1*Vaibhav Kumar¹Ashok Kumar Parihar¹Sudhir Kumar Jha¹KULDEEP KUMAR¹Rishikesh Kumar¹Manmohan Deo¹Surendra Kumar Meena²Rajeev Kumar³M Senthil Kumar¹GIRISH PRASAD DIXIT¹

• ¹Indian Institute of Pulses Research (ICAR), Kanpur, Uttar Pradesh, India
• ²Indian Grassland and Fodder Research Institute (ICAR), Jhānsi, Uttar Pradesh, India
• ³Indian Institute of Sugarcane Research (ICAR), Lucknow, Uttar Pradesh, India

α-galactooligosaccharides (α-GOS) are a class of non-nutritional compounds present in pulses. These carbohydrates are associated with irritable bowel syndrome (IBS). This study explored the genotypic variability for α-GOS content in field pea and cowpea cultivars using high-performance liquid chromatography coupled with a refractive index detector (HPLC-RI).Verbacose, stachyose and raffinose were detected in field pea, whereas in cowpea, only stachyose and raffinose were detected, except the cultivar RC 101 in which verbascose was also found. The total α-GOS content varied from 65.89 ± 0.21 mg/g DW to 101.84 ± 0.33 mg/g DW and 78.78 ± 0.65 mg/g DW to 108.00 ± 0.49 mg/g DW in field pea and cowpea, respectively. The cultivars IPFD 16-13 and KBC 7 were identified as low α-GOS cultivars of field pea and cowpea, respectively. Further, three low-cost, sustainable processing methods, viz. soaking, cooking, and malting (12, 24, 48 and 72 hours), were investigated for their effect on the α-GOS content of field pea and cowpea. The results from this study show that malting with 72 hours of germination emerged as the most effective method in reducing the total α-GOS content. It reduced verbascose and stachyose content by 74.6% and 67.43% in field pea and by 44.82% and 69.64% in cowpea.