Changes in Malonaldehyde Content of Some Roasted Legumes

Abstract

The effect of roasting alone or steeping of grains before roasting on malonaldehyde (MDA) contents of some
legumes was investigated. The legumes studied were Beni seed (Sesanum indicum), African bread fruit (Treculia
Africana), Cowpea (Vigna unguiculata), Ground bean (Vigna subterrranea), Ground nut (Arachis hypogea),
Local yam bean (Stenostylis stenocarpa), Locust bean (Cerotonia siliquia), and Soy bean (Glycine max). Roasting
alone prior to steeping significantly (p 0.05) increased the MDA contents in all the legumes. This increase
ranged from 8.79±4.29% in cowpea-Ife brown to 140.20±56.84% in cowpea L-25. Steeping before roasting
resulted in a significant decrease in MDA contents in the legumes ranging from 33.02±14.14% in Beni seed to
63.11±32.39% in cowpea L-25. These findings indicate that steeping before roasting may be a safer and more
desirable way of processing these legumes given the growing reports about mutagenicity and carcinogenicity of
MDA in animal models.