Influence of Drying Methods on Flour Quality and Cyanide Content of Cassava Root Tuber

Abstract

The aim of this particular work was to study effect of different drying methods on the quality attributes of cassava flour focusing on physico-chemical properties (moisture, water activity, pH and titratable acidity), functional properties (water and oil absorption capacity, bulk density, foaming capacity and stability) and also antinutritional factor specially cyanide content in dried cassava tuber. Losses were determined in flours after drying of slices. Prior to drying, samples were washed with clean water to remove adhering soil and other undesirable materials. The samples were sorted and hand-peeled using clean, sharp knives and then sliced into sizes of 2 to 2.5cm in thickness. Drying methods like tray drying, oven drying and sun drying were investigated. The physico-chemical properties were 11.45, 9.67, 9.23 of moisture content, 0.59, 0.54, 0.48 of water activity, 6.55, 6.74, 6.92 of pH, 2.35, 2.36, 2.33 of titratable acidity for tray dried, oven dried and sun dried cassava flours respectively using different drying time. The low moisture observed for all prepared cassava flours is a good indicator of their potential to have longer shelf life. All prepared flours predict lower water activity (< 0.5). These shows using these drying methodologies and the respective drying time of the prepared flours were safe from microbial growth during storage time. The functional properties were 0.58, 0.55, 0.49g/ml, 0.64, 0.78, 0.65ml/g, 2.11, 2.03, 1.85ml/g, 2.45, 2.73, 2.55%, and 2.34, 2.13, 1.97% of bulk density, water absorption capacity, oil absorption capacity, foam capacity and foam stability for tray dried, oven dried and sun dried cassava flours respectively. Sun dried cassava flour samples shows a lower cyanide content whereas tray dried cassava flour samples had a good functional property.