African Journal of Agriculture and Food Security

African Journal of Agriculture and Food Security ISSN: 2375-1177 Vol. 13 (5), pp. 001-011, May, 2025. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research paper

Nutritional Composition and Anti-Nutrient Variation in Mucuna Beans: A Study of Processing Techniques

J. B. Mugendi1*, E. N. M. Njagi2, E. N. Kuria1, M. A. Mwasaru3, J. G. Mureithi4 and Z. Apostolides5

1Department of Foods and Nutrition, Kenyatta University, P. O. Box 43844-00100, Nairobi, Kenya.
2Department of Biochemistry and Biotechnology, Kenyatta University P. O. Box 43844-00100, Nairobi, Kenya.
3Department of Foods Science and Post Harvest Technology, JKUAT, P. O. Box 62000-00200, Nairobi, Kenya.
4Kenya Agricultural Research Institute (HQ), P. O. Box 57811-00100, Nairobi, Kenya.
5Department of Biochemistry, University of Pretoria, Pretoria 0002, South Africa.

Accepted 8 March, 2025

Mucuna bean (Mucuna pruriens) is an indigenous legume promoted in Kenya as a green manure cover crop. It contains high protein but it is under - utilized due to the presence of 3, 4-dihydroxy- L-phenylalanine (L-Dopa) and other anti nutritional compounds. To improve its nutritional potential as a protein source, mucuna bean was processed and evaluated for nutritional composition. Effects of processing at different pH, temperature and particle size, autoclaving, germination and fermentation on the contents of anti-nutritional compounds and crude protein were investigated. Raw beans contained high crude protein (27.9 g/100-1). Contents of ether extract; crude fibre and ash were 3.7, 7.9 and 3.5 g/100-1, respectively. Mineral content was comparable to that of common pulses. Raw whole mucuna bean contained high L-Dopa (7.0 g/100-1) content. Other anti-nutritional compounds included total phenols 7.1 g/100-1, trypsin inhibitor activity (TIA) 5.1 TIU and phytates 0.9 g/100-1. All processing techniques, except roasting, reduced levels of L-dopa by > 95% while less than 15% of protein was lost. Soaking dehulled bean in acidic medium (pH 3.2) at 60°C for 48 h reduced L-Dopa content to the recommended safe level of 0.1%. Processing mucuna bean increased its nutritional value and potential to improve food security.

Key words: Mucuna bean, anti-nutritional compounds, L-Dopa, processing methods.