Bambara groundnut (Vigna subterranea (L.) Verdc.) flour: A functional ingredient to favour the use of an unexploited sustainable protein source

• Published in: PloS one 2018-10, Vol.13 (10), p.e0205776-e0205776
• Main Authors: Mubaiwa, Juliet, Fogliano, Vincenzo, Chidewe, Cathrine, Linnemann, Anita R
• Format: Article
• Language: English
• Subjects: Absorption; Amino acids; Bambara groundnut; Biology and Life Sciences; Carbohydrates - analysis; Chemical composition; Cooking; Emulsification; Flour; Flour - analysis; Flour - standards; Foaming; Food processing; Food production; Food Quality; Food science; Food Supply; Gelation; Groundnuts; Heat conductivity; Heat treatment; Heat treatments; Households; Legumes; Medicine and Health Sciences; Methods; Nutrient content; Nutrition; Organic chemistry; Physical properties; Physical Sciences; Plant Proteins, Dietary - analysis; Protein sources; Proteins; Roasting; Seeds; Soaking; Stability; Starch; Sucrose; Sugar; Vigna - chemistry; Vigna subterranea
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0205776

Variability in dehulling efficiency, colour, chemical composition and selected functional properties of raw and pre-treated bambara groundnut (Vigna subterranea (L.) Verdc.) (BG) flour from red and black-eye varieties were studied. Functional properties were water and oil absorption, gelation, pasting, emulsification and foaming capacity. Pre-treatment of seeds (i.e. soaking, roasting and combined soaking and roasting) improved dehulling efficiency of BG varieties. Protein content of flour ranged from 15.6-19.6%, starch from 47.8-52.0% and sucrose from 1.9-5%. An improvement was observed for protein and ash content of pre-treated flour compared to raw flour. Heat treatments increased onset gelatinization temperature of flour. Black-eye BG flours that had higher starch content, also had better gelation capacity than red BG flours. All pre-treatment methods decreased flour emulsification capacity and stability. Dry-roasting caused a greater decline than other methods, whereas soaking had little effect on emulsion stability. Further, soaking increased foaming capacity, whilst a decline was observed in roasted flour. All pre-treatment methods increased oil absorption capacity of both BG flour varieties. Overall, soaked and combined soaked and roasted flour is recommended for BG flour to be incorporated in food products.