The hard-to-cook nature of Vigna subterranean constitutes an hindrance to its utilisation. Two species of a hard-to-cook legume Vigna subterranean were subjected to hydrothermal processing after soaking. This study is aimed at investigating the effects of soaking followed by hydrothermal processing on the cooking times. The seeds of two species of Vigna subterranean (the cream coloured specie and the mottled coloured specie,) were processed by four different hydrothermal techniques before and after aqueous soaking to varying hydration levels. Soaking of the seeds to varying hydration levels before processing by hydrothermal techniques induced decrease in the cooking times. Highest percentage reduction of 66.24% was recorded when the seed of the cream coloured variety was boiled at elevated pressure.

Vigna subterranean, hard-to-cook, hydrothermal techniques, cooking times