CHEMICAL, FUNCTIONAL AND SENSORY PROPERTIES OF MANGO KERNEL AND WHEAT FLOUR AND THEIR BLENDS FOR BREAD MAKING

Abstract

The research is aimed at the possibility of producing high nutritive flour from mango (Magnifera indica) kernel as a supplement to wheat flour for baking bread and incorporation into other selected food products. Fresh mango seed kernels were soaked in sulphited solution at 27+2 oC for 72 hours to reduce tannin, drained, dried and milled to produce mango seed kernel flour. The chemical composition and functional properties of mango seed kernel flour, wheat flour and blends of flour containing 10%, 20%, 30% and 40% mango seed kernel flour as substituting levels for wheat flour were investigated. Results of processing revealed that maximum reduction of tannin, saponin, and oxalate contents and increment of total phenolic content and radical scavenging activities were achieved in mango seed kernel. Crude protein and crude fat, were significantly higher (P<0.05) in composite flour variants when compared with standard wheat flour while ash content was significantly lower (P<0.05) in composite flour variants when compared with standard wheat flour. There was significant increase in the mineral content of mango kernel after soaking for 72 hours. The functional properties results revealed that flour blends containing 20%, 30 % and 40% had higher swelling power, water absorption capacity, emulsion capacity and stability respectively when compared with standard wheat flour. There was no significant difference (P<0.05) in the oil absorption capacity of flour blends containing 10% and 20% mango seed kernel flour and 100% wheat flour. Also, dipersibility of blended flour variants were significantly lower (P<0.05) than in 100% wheat flour. Colour analysis showed a gradual reduction in the whiteness (L*) and yellowness (b*) of the flour while redness (a*) increased. The dough characteristics of mixtures of wheat and mango kernel blends showed higher water absorption capacity when compared with control wheat. The dough development time of wheat and mango kernel composite flours ranged from 01.40 to 02.22 minutes, with no large difference with increase of mango kernel flour. The mixing tolerance index and breakdown time of mixtures tended to increase as the proportion of mango kernel flour increased. There was no significant difference in the loaf weight, loaf volume, specific volume and baking loss of the loaves baked with composite flour when compared with control. The loaf heights gradually reduced as the proportion of mango kernel ratio increased from 5.5 cm in 10% to 4.4 cm in 20% and 30% and to 4.5 cm in 40% respectively. The moisture content of control bread was minimum (26%) in control sample (100% wheat) and increased gradually in composite flour breads from 26.7% in 10% to 29% in 40%. No significant difference was found in the color, texture, taste, aroma and overall acceptability of bread containing 10% mango kernel flour when compared with the control sample. This research work gave an insight into how mango kernel flour could be utilized as part substitute in bread production