Water absorption characteristics of Canarium Schweinfurthii fruits

Abstract

Water absorption characteristics of two varieties of Canarium Schweinfurthii engl. fruit (Canarium Schweinfurthii engl. long and short) essential for predicting their suitable absorption conditions was investigated at three different temperatures (35, 50, 65 °C). Increase in moisture content of the fruits was measured at one-hour interval until constant values were obtained after five successive intervals of moisture measurements. Loss of soluble constituents, textural and nutritive qualities of the rehydrated products and their thermodynamic behavior were also measured and calculated. The results obtained revealed that saturation time for 35, 50 and 65 °C of long and short varieties are 14, 18 and 40 h and 18, 22 and 36 h respectively. Rate of absorption of the fruits differ significantly (p > 0.05) with temperature and not with the variety. Water absorption rate of Canarium Schweinfurthii engl. long and short varieties are 2.71 and 2.25 kg/h respectively. The moisture bearing capacity, textural, and nutritive qualities of the reconstituted products showed no significant difference among varieties at different temperatures used. Fruits soaked at 35 °C produced reusable residual water, retained their nutritive values and soluble constituent more than other soaking temperatures studied. However, the absorption reaction is endothermic with negative entropy and Gibbs energy values were above zero. Midilli model had the best quality for describing the absorption characteristics of both Canarium Schweifurthii engl. fruits. Keywords: Absorption, Canarium, Thermodynamics, Temperature, Fruits, Moisture