|
Click on “Download PDF” for the PDF version or on the title for the HTML version. If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. Moisture Sorption Isotherm Characteristics of Dehydrated Sorghum Flour (“Ogi”)Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: 2012 Dallas, Texas, July 29 - August 1, 2012 121336839.(doi:10.13031/2013.41710)Authors: Ajiboye Solomon Oyerinde, Ayodeji John Mustapha Keywords: moisture adsorption, sorghum flour, equilibrium moisture content, moisture isotherm, storage stability Dehydrated sorghum flour (ogi) is obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked material, and fermentation for another 3 to 4 days. Typically the fermented product is boiled into a pap or cooked into a stiff porridge. However, the fermented product cannot be easily handled or stored and does not have a long shelf life (typically less than a week). Dehydrating the fermented product into flour is one of the ways that is being employed to overcome these problems. Equilibrium moisture content (emc) of dehydrated sorghum flour (aka ogi) was therefore determined at two temperatures of 25oC and 40oC and four salt solutions. Zinc Chloride (ZnCl2), Potassium Acetate (KC2H3O2), Calcium Chloride (CaCl2) and Sodium Chloride (NaCl) salts were prepared to correspond to equilibrium relative humidities of 10.0% to 75.4%. The moisture sorption characteristics of the sorghum product showed the characteristics S-shaped sorption isotherm curve that is typically obtained for agricultural products. The equilibrium data and the monomolecular layer moisture content values were estimated using the Brunauer-Emmett-Teller (BET) equation. The moisture content range for optimum storage of the dehydrated sorghum flour lies between 2.84 % to 3.69 % at 25oC and 6.84 % and 7.67 % at 40oC. The information obtained from this study will help in the design and selection of storage and packaging systems for dehydrated sorghum flour. (Download PDF) (Export to EndNotes)
|