Effect of Processing Methods on the Quality of Flour and Bread from African Breadfruit Kernel Flour

Abstract

The consumer demand for composite flour bread is increasing. African breadfruit seed with high protein quantity and quality is a good complement for composite flour bread.  The study investigated the effect of processing methods on the quality of African bread fruit seed flour (ABKF) for bread making. Flours were prepared from boiled, toasted and fermented African bread fruit kernels and evaluated for their chemical composition and functional properties. Each of the flours (30%) was used to substitute 70% wheat flour in breads, which were assessed for their physical, chemical and sensory properties. Breads from untreated ABKF and 100% wheat flour (WF) served as controls. Toasting increased the protein, ash and crude fiber contents of ABKF. Fermentation increased the protein content while boiling decreased it. Toasting, fermentation and boiling significantly decreased (P < 0.05) the oxalates, phytates, tannins and HCN contents of the seed. All the treatments improved (P < 0.05) water absorption capacity (125-180%) of ABKF in relation to the control. Only fermentation reduced (P < 0.05) oil absorption capacity but improved foaming and emulsification properties of ABSF. Breads containing toasted ABKF had higher weight, height, length and volume than the other breads. Breads containing fermented ABKF had the highest proofing ability and specific loaf volume. Toasting and fermentation improved the flavour of bread more than the other treatments. However, the breads containing fermented ABKF received significantly lower (P < 0.05) scores for crust colour, crumb colour and texture than the other breads. Breads containing toasted ABKF had significantly higher (P < 0.05) scores for flavour, texture, taste and overall acceptability than the other breads including 100% WF bread. These results suggested that toasted ABKF could be used as wheat flour supplement in bread making.

Keywords: African breadfruit, chemical composition, functional properties, sensory quality, supplemented bread, processing