Drying Kinetics, Physico-chemical and Nutritional Characteristics of "Kindimu", a Fermented Milk-Based-Sorghum-Flour

Abstract

"Kindimu", a fermented milk-based cereal foods made by sun drying a mixture of fermented milk and cereal flour is a common flour ingredient in the central African region. A study was carried out to evaluate the effect of processing methods on the drying behaviour, functional and nutritional quality of such a food prepared from sorghum flour and fermented milk. A mixture of 1 part sorghum flour (germinated or non - germinated) and the 2 part (w/w) on fermented milk was coated on aluminium trays to a depth of 5mm and dried at 50, 65 or 80°C. Results obtained indicated that a simple mass transfer equation Ln [(C-C*)/(Co-C*)]= -(K/L)t can be used to model the drying behaviour of the fermented milk -sorghum flour mixtures. The magnitude of mass transfer coefficient K, increased with drying temperature and the germination of sorghum. Germination and addition of milk increased the in vitro protein digestibility of sorghum flour by 19.03%, protein solubility by 11.5% and available lysine content by an average of 3.04% and reduced the phytate content by 30%. The water absorption capacity of flours was equally reduced by an average of 4%.


Key Words: Fermented milk, sorghum, malting, drying kinetic, physico-chemical properties, nutritional properties.


Journal of Food Technology in Africa Vol.9(1) 2004: 17-22