Prediction of Shelf Life of Dakuwa (Nigerian cereal/groundnut snack) Using pH as Index of Acceptability

Abstract

This study was undertaken to establish the effect of pH on the acceptability of dakuwa. Dakuwa was prepared by malting and milling maize grains and groundnut. Maize flour and groundnut paste were mixed together in equal ratios with the addition of sugar and red pepper. pH of fresh dakuwa was varied using citric acid and subjected to sensory evaluation in order to establish the relationship between pH and acceptability of dakuwa. Accelerated storage test was also carried out in order to determine the kinetics of pH change and kinetics of pH change was tested using zero and first order reaction relationships. Linear regression was used to determine Arrhenius equation parameters and the relationship between pH and acceptability. Decreasing pH reduced dakuwa acceptability. Order of pH change was adequately described by both zero and first orders of reaction. From the data generated, using first order reaction kinetics, a relationship was derived which can be used to estimate the shelf life of dakuwa on the basis of pH.

Keywords: Dakuwa, pH, acceptability, kinetics, sensory evaluation, accelerated storage, Arrhenius equation, regression, temperature, shelf-life