Influence of oil content on sorption isotherms of four varieties of peanutat 25 degrees C

The sorption isotherms of peanuts at 25 degreesC were determined gravimetri cally, in the range of water activity (a,) 0.577-0.903. The most common pea nut varieties in Argentina (Flour Rummer, Tobaldo, Colorado and Roata), wer e used with 47.2%, 43.9%, 47.6% and 50.9% (dry basis) of oil content respec tively. To check if there is any difference among varieties, the statistica l methodology used with the transformed data allows comparison of the adsor ption isotherms of peanut varieties as a whole. The four peanut varieties s how significant differences in moisture sorption even if moisture content i s expressed in an oil-free basis. (C) 2000 Elsevier Science Ltd. All rights reserved.