Studies on kolanut and cashew kernels: moisture adsorption isotherm, proximate composition, and functional properties

Kolanut (Cola nitida) and cashew (Anacardium occidentale) kernels:were analysed and their moisture adsorption isotherms, proximate composition, and functional properties were compared. The dried powdered sample of kolanut contained 69% carbohydrate, 18% crude fat and 3.1% ash by weight, while the cashew sample had 51% crude fat, 36% crude protein, 0.3% ash and 3.4% carbohydrate. These differences significantly affected their relative water and oil absorption capacities, least gelation concentration, bulk density,:and emulsion properties. However, both samples would retain nutritional integrity when stored in atmospheres with water activities of up to 0.68 for kolanut and 0.85 for cashew kernels. The Brunauer-Emmett-Teller (BET) and Henderson mathematical models described both isotherms with less than 2% mean relative deviation. (C) 1999 Elsevier Science Ltd. All rights reserved.