Effect of cassava varieties on the sorption isotherm of tapioca grits

Abstract

Cassava (Manihot esculenta Cranzt) deteriorates rapidly. Hence it is processed into various products within 2 to 3 days after harvesting. For this work, tapioca was produced from three different varieties of cassava. They are Odongbo, Okoiyawo and TMS30572. The sorption isotherm for the tapioca grits from three different varieties of cassava at temperatures 25, 32 and 45°C were determined experimentally and modelled using five different models. Using analysis of variance at 0.01 level, it was shown that the experimental sorption isotherms of the tapioca from the various cassava varieties are not significantly different from each other. However, the Guggenheim (1966), Anderson (1946) & de Boer (1953 (GAB) model gave the best fit for sorption isotherm of tapioca from either the Odongbo or Okoiyawo varieties, while the exponential model was the best for that from TMS30572 variety.

Adsorption isotherms and thermodynamics properties of water yam flour

“…The decrease in EMC as temperature increased could be because at higher temperatures, the activation energy of the water molecules changes to higher energy levels, the bonds become less stable and break away from water-binding sites of the flour (Moreira et al, 2008). Similar trends for the same temperature effects have been reported by Sanni et al (1997), Onayemi and Oluwamukomi (1987) and Adebowale et al (2007) for fufu, traditional yam flour (elubo) and tapioca grits, respectively. Higher water activity resulted in progressively higher EMC values at constant temperature.…”

Thermodynamic analysis of sorption isotherms of cassava (Manihot esculenta)

“…According to these results, GAB model was considered the best model for predicting the equilibrium moisture content of cassava. The GAB model has a theoretical basis, while the other models are empirical or semi-empirical (Adebowale et al 2007). According to Lomauro et al (1985), the GAB model provides the best fit for more than 50 % of the fruits, meats and vegetables analysed.…”

Effects of solid content and temperature on viscosity of tapioca meal

“…Oyewole and Obieze (1995) reported some preliminary works on the traditional processing of cassava to tapioca grits. Our earlier studies investigated the effect of cassava variety and roasting methods, respectively on the sorption isotherms of tapioca grits (Adebowale et al 2006 and2007). While Adebowale et al (2008) reported that peak and hot paste viscosities are the key pasting parameters in characterizing tapioca grits from different cassava varieties and roasting methods.…”

“…Tapioca grit is a partially gelatinized dried cassava starch, which appears as flakes or irregularly shaped granules (Adebowale et al 2006). It is usually soaked, and cooked in water to form tapioca meal.…”

“…Sugar and/or milk are added before consumption. It is consumed in many parts of West Africa and widely accepted as a convenience (Adebowale et al 2006). Oyewole and Obieze (1995) reported some preliminary works on the traditional processing of cassava to tapioca grits.…”