Effect of Soy Flour and Maize Flour Addition on Phase Separation in Moi- Moi from Soaked Cowpea (Vigna unguiculata) and Cowpea Flour from Different Cowpea Varieties

Abstract

Two improved varieties of cowpea (IT89KO and IT90K-76) and one local variety (lsiocha) were used to investigate the effects of added soyflour and maize flour on the phase separation in moi-moi made from soaked cowpea and cowpea flour. Different levels (5%, 10%, 15%, 20% and 25%) of maize flour, soyflour and a 1:1 blend of soyflour and maize flour (soy/maize flour) were separately added. The moi-moi from the different combinations was evaluated for phase separation and per cent height of the upper layer calculated. Soaking of cowpea reduced the size of the
upper layer in moi-moi compared with the use of cowpea flour. The addition of maize flour or the soy/maize flour reduced the upper layer compared with when either flour was added alone. The upper layer of moi-moi made from cowpea flour with added soy flour (21.20%) was significantly higher (p < 0.05) than moi-moi from soaked cowpea with
added soy flour (15.2%). Moi-moi with added maize flour made from cowpea flour produced a significantly (p < 0.05) higher mean per cent upper layer (19.72%) compared with that from soaked cowpea (8.95%). Addition of soyflour produced the greatest upper layer for all varieties used. There were no significant (p > 0.05) differences in the per cent
upper layers for moi-moi from all cowpea varieties when maize flour was added. Increasing the proportion of added flours increased the size of the upper layer. Complete prevention of the occurrence of phase separation in moi-moi by addition of soy flour and maize flour alone is not feasible.

Keywords: Phase separation, moi-moi, soyflour, maize flour and cowpea varieties.