Nnamdi Azikiwe University | Nigeria
Title: Comparative studies of the proximate, microscopic and thermal properties of processed maize, wheat, millet, cassava and bambara nut flours
This research investigated and compared the proximate composition, microscopic and thermal properties of some grains (maize, wheat, and millet), a root crop (cassava) and a leguminous crop (bambara nut) with the intent to formulate novel food product with the desired characteristics for industrial processing. Native cassava flour is known to exhibit physicochemical characteristics that discourages its applications in food systems. However, composite flour formulation and the use of additives have the capacity to encourage the use of unmodified cassava flour to process food of an acceptable standard. Bambara nut is however, a leguminous crop but very high in ash and mineral contents which affects the taste and flavour of products produced from it. Furthermore, the high mineral composition of bambara nut contributes to increased anti-nutrients that contribute to high energy requirement during processing. Thus, these studies were carried out in response to processing needs. The results obtained showed increased starchy materials of the maize grain compared to the other grains while the bambara nut, been a legume, has the least carbohydrate content. Microscopically, the millet flour showed silvered-white indentations that evidenced presence of protein in the intact structure, unlike the other grains. The increased content of protein in the maize could be attributed to increased activity of α-amylase in the maize grain soaked for 48 hrs. The DSC of the flours indicates the A+V-type polymorphs were present in the flours. Wheat and maize flours contained high values of the amylose that could have contributed to the increased values of the enthalpy in their flours, although maturity of the grain during harvest could influence the amylose content and consequently, the enthalpy of foods. The FTIR-Spectroscopic studies showed that the millet flour possessed more ordered structure compared to the other grains. However, the bambara nut flour has the highest ordered structure. Furthermore, cassava with more peaks contained more polymorphs and is expected to possess more complex structure.