Effect of pre-treatment and storage condition on the physicochemical properties of taro (Colocasia esculenta [L.] Schott) flour

Abstract

Taro is an important crop in Ghana. Matured freshly harvested taro was pre-treated for 2 min in hot water blanching at 100℃, 2% w/v sodium chloride, 2% w/v sodium hypochlorite, 50% v/v ethanol and distilled water as control. Pre-treatment samples were subsequently divided into two sub-groups and spread in a single layer in cardboard boxes, stored at cold room (4 - 5℃) and tropical ambient temperature conditions (28 ± 3℃). Samples were randomly selected from the two storage conditions for flour processing at period 0, 7, 14 and 21 days of storage. Reducing sugars and water activity were affected by the pretreatments. Blanched samples showed highest reducing sugar content whereas samples treated with 2% sodium chloride solution had the lowest. The highest water activity was recorded in 2% sodium chloride pre-treatments. The least water activity was observed for control samples. Both ambient and cold storage conditions did not have a significant influence on the parameters examined. Taro flour stored for 21 days neither changed their colour or reducing sugar content. However, water activity increased over 21 days of storage period. Significant changes did not occurred in the colour of flour samples particularly among L* and Hue angle values. However, colour of the pre-treatments and storage durations differed significantly from their control