DEVELOPMENT OF OPTIMIZED SUBSTITUTION RATIO FOR WHEAT-CASSAVA-AFRICAN YAM BEAN FLOUR COMPOSITE FOR NIGERIAN BREAD INDUSTRIES

Authors

  • IE Nwatu DEPARTMENT OF AGRICULTURAL AND BIORESOURCES ENGINEERING, NNAMDI AZIKIWE UNIVERSITY, AWKA, ANAMBRA STATE, NIGERIA
  • OC Nwajinka DEPARTMENT OF AGRICULTURAL AND BIORESOURCES ENGINEERING, NNAMDI AZIKIWE UNIVERSITY, AWKA, ANAMBRA STATE, NIGERIA
  • AB Muochebe DEPARTMENT OF AGRICULTURAL AND BIORESOURCES ENGINEERING, NNAMDI AZIKIWE UNIVERSITY, AWKA, ANAMBRA STATE, NIGERIA

Keywords:

Bread, wheat, Cassava, African Yam Bean, Flour, Dough, Loaf Specific Volume, Crumb Hardness, Crumb Colour Index

Abstract

An optimization study of the mix ratio for substitution of Wheat flour with Cassava and African Yam Bean flours (AYB) was carried out and reported in this paper. The aim was to obtain a mix ratio that would optimise selected physical properties of the bread. Wheat flour was substituted with Cassava and African Yam Bean flours at different levels:  80% to 100% of wheat, 0% to 10% of cassava flour and 0% to 10% for AYB flour. The experiment was conducted in mixture design which was generated and analysed by Design-Expert Software 11 version. The Composite dough was prepared in different mix ratios according to the design matrix and subsequently baked under the same conditions and analysed for the following loaf quality attributes: Loaf Specific Volume, Bread Crumb Hardness and Crumb Colour Index as response variables. The objective functions were to maximize Loaf Specific Volume, minimize Wheat flour, Bread Crumb Hardness and Crumb Colour Index to obtain the most suitable substitution ratio acceptable to consumers. Predictive models for the response variables were developed with the coefficient of determination (R2) of 0.991 for Loaf Specific Volume (LSV) while that of Bread Crumb Hardness (BCH) and Crumb Colour Index (CCI) were 0.834 and 0.895 respectively at 95% confidence interval (CI).The predicted optimal substitution ratio was obtained as follows: 88% Wheat flour, 10% Cassava flour, and 2% AYB flour. At this formulation, the predicted Loaf Specific Volume was 2.11cm3/g, Bread Crumb Hardness was 25.12N, and Crumb Colour Index was 18.88.The study shows that addition of 2% of AYB flour in the formulation would help to optimise the LSV, BCH and the CCI of the Wheat-Cassava flour bread at the mix ratio of 88:10. Application of the results of this study in bread industries will reduce the cost of bread in Nigeria, which is influenced by the rising cost of imported wheat. This is a significant development because wheat flour was the sole baking flour in Nigeria before wheat substitution initiative.

 

http://dx.doi.org/10.4314/njt.v39i4.33

Published

2020-09-30

Issue

Section

Agricultural, Bioresources, Biomedical, Food, Environmental & Water Resources Engineering