Effect of different cooking treatments of Mucuna beans on its L-Dopa content
García Echeverría, C.Luz.; Bressani, R.
Archivos Latinoamericanos de Nutricion 56(2): 175-184
2006
ISSN/ISBN: 0004-0622 PMID: 17024964 Document Number: 604502
The main limiting factor in the consumption of velvet beans (Mucuna) by humans is its relative high L-dihydroxyphenylalanine (L-dopa) content, with levels as high as 9%. Conventional cooking methods are not sufficiently effective in reducing the levels of L-dopa. In this study, the effect of microwave cooking, utilizing vapour and in water solutions at pH 3, 6, 7, 9 or 11, on the L-dopa content of velvet beans was determined. Alkaline pH was achieved using sodium hydroxide, potassium hydroxide and calcium hydroxide, while acid pH by hydrochloric acid. The initial cooking time was fixed at 6 h. The processed bean samples were dried, ground and analysed for L-dopa and protein. The ground samples were further washed with boiling water for 1, 3 and 6 minutes, then dried and analysed. The results showed that none of the treatments evaluated was capable of eliminating L-dopa from the velvet beans. The samples treated with calcium hydroxide (pH 9) and washed with hot water had an L-dopa reduction of 80.4%. The alkaline ions had no effect. Reducing the particle size appeared to be the most effective method, as shown by the other workers.