Application du procédé séchage-friture aux amandes de karité : cinétique de séchage

Abstract

Fresh kernel of shea (Butyrospermum parkii (G. Don) Kotschy) have been dehydrated by a deep-fat frying dehydration process with view to extract subsequently the shea butter. The deep-fatfrying dehydration significantly reduces the water content of the shea kernels within a very short period of time. The effects of some operating parameters on the mass transfers during deep-frying showed that the rate of drying was linked to the temperature of the bath, the frying time, the thickness of the kernels, and the mass ratio kernels/butter. A final moisture of about 5% was obtained after 10 minutes of frying at 150-180 °C applied to kernels cut into slices of 2 to 6 mm thick with a weight ratio kernels/butter of less than 0.04. The residual moisture content can be expressed using mathematical models taking into account the operating parameters. A negative linear correlation was fund between the water and butter contents. Such a rapid frying was considered to improve the quality of the fat extracted from shea kernels that have been preserved from moisture degradation during processing.

Keywords

• Butyrospermum parkii
• shea butter
• deep-fat frying dehydration
• kinetic of drying