Effect of Soaking and Boiling on Anti-nutritional Factors, Oligosaccharide Contents and Protein Digestibility of Newly Developed Bambara Groundnut Cultivars

Abstract

Newly developed Bambara groundnut (Vigna subterranea L.) seeds (Accessions No: TVSU 5 -Bambara Groundnut White (BGW) and TVSU 146 -Bambara Groundnut Brown (BGB)) were collected from International Institute of Tropical Agriculture (IITA), Nigeria, planted and harvested. The effects of processing methods (soaking and boiling) on anti-nutritional factors and oligosaccharides content and protein digestibility of BGW and BGB compared with Bambara groundnut commercial (BGC) seeds were investigated. Soaking and boiling significantly reduced the anti-nutritional factors of the samples and the effect increased as processing time was elongated. Sample BGC had lower anti-nutritional factors than BGW and BGB after soaking for 48 h. Tannin contents of the samples were reduced drastically by 99 % throughout the soaking periods. Greatest loss in raffinose level was observed in BGB (59%) and BGW (50%) after boiling for 60 min compared with BGC (43%). The loss in stachyose content of the samples varies with processing and BGC (59%) had greatest loss after boiling for 60 min while soaking for 48 h reduced that of BGB and BGW by 57 and 35%, respectively. Boiling for 60 min increased the in vitro protein digestibility of BGB (89.34 %) compared with BGW (87.48%) and BGC (82.89%). Overall, the results demonstrated that soaking and boiling of newly developed Bambara groundnut seeds could improve the nutritive quality of the seeds.

Bambara Groundnut: An Underutilized Leguminous Crop for Global Food Security and Nutrition

“…There is considerable variation (1.4 and 9.7%) in the reported values of lipid content in Bambara groundnut ( 38 , 39 ). The majority of fatty acids in Bambara groundnut are unsaturated, predominated by oleic and linoleic acids (omega-6) ( 39 , 43 ). Palmitic acid is the third most abundant fatty acid, and linolenic acid (omega-3) is present at a low concentration.…”

“…Inhibition of protease can negatively affect protein digestion and subsequently impede its absorption. Furthermore, low trypsin level can result in increased pancreatic secretory activity, thereby causing pancreatic hypertrophy ( 43 ). The reported levels of ANFs among different Bambara groundnut cultivars vary widely (condensed tannins, 0.0011–18.61 mg/g; phytic acid, 1.10–15.11 mg/g; trypsin inhibitor, 0.06–73.40 TI mg/g).…”

“…Pectins can bind to metal cations such as calcium, zinc, and iron, which, not only reduces mineral bioavailability, but affects the cookability of the legume ( 52 ). Raffinose and stachyose, the flatus-causing alpha-oligosaccharides, are also present in Bambara groundnut ( 43 , 55 ). Other ANFs such as oxalate, hydrogen cyanide, and saponins have also been detected in Bambara groundnut ( 43 , 46 , 56 ).…”

“…Raffinose and stachyose, the flatus-causing alpha-oligosaccharides, are also present in Bambara groundnut ( 43 , 55 ). Other ANFs such as oxalate, hydrogen cyanide, and saponins have also been detected in Bambara groundnut ( 43 , 46 , 56 ).…”

In Vitro and In Situ Degradation Characteristics and Rumen Fermentation Products of Moringa oleifera Harvested at Three Different Ages

“…However, the presence of some anti-nutritional factors such as oxalates (41 g/kg), saponins (12 g/kg), and phytates (31 g/kg) (Gupta et al, 1989) may compromise its utilization as a forage source. It is also true that such anti-nutritional factors are water-soluble and can be removed by soaking and boiling in water (Adeleke et al, 2017) or easily extracted in aqueous ethanol (Gupta et al, 1989). The utilization of such forage material as a source of fresh forage in ruminant species thus depends on the balance between the adequacy of nutrient composition and the deleterious effect of the anti-nutritive factors in the fresh material.…”