Influence of pH and sodium chloride on selected functional and physical properties of African breadfruit (Treculia africana Decne) kernel flour

African breadfruit seeds were cleaned, parboiled (98 °C) for 15min, drained and dehulled. The kernels were sun-dried, then milled andsieved into flour. Nitrogen solubility (NS), water absorption capacity(WAC), emulsion activity (EA), viscosity, foaming and emulsifyingproperties of the flour were determined as functions of pH and NaClconcentration. The NS was pH dependent with a minimum at pH 4 andmaximum at pH 10. The flour also exhibited minimum and maximum foamcapacity at pH 4 and 10, respectively. The minimum emulsion activity wasat pH 4, a value which increased from 7–16% at pH 12. The addition ofNaCl at concentrations of 0.2 to 0.4 M improved WAC, NS, foamingand emulsion properties of the flour. Sodium chloride enhanced NS of theflour at pH 4–6 and EA at pH 2–8.The EA at pH 2, 10 and 12 correlated negatively (r = –0.30) with NaClconcentration levels; however, the correlation was not significant (p> 0.05). The flour dispersions had lower viscosities at acid pH and in thepresence of NaCl than at neutral and alkaline pH values. Results indicatedthe flour could be used in food product supplementation.