Modeling of Water Sorption Isotherms Characteristics of Spray-Dried Cherimoya (Annona cherimola) Puree

作者：Munio Maria M^*; Guadix Emilia M; Guadix Antonio

来源：Particulate Science and Technology, 2015, 33(3): 264-272.

DOI：10.1080/02726351.2014.970310

• Cherimoya
• compensation theory
• isosteric heat of sorption
• isotherm
• spray drying

Spray drying is a solution to preserve food products from spoiling and moisture adsorption isotherms of dry products can be used to predict their shelf life during storage and distribution. Sorption isotherms of spray-dried cherimoya puree were determined using a gravimetric method between 10 degrees C and 50 degrees C and water activities from 0.05 to 0.96. The data obtained were fitted to Guggenheim, Anderson, and De Boer (GAB), GAB modified, Henderson modified, Oswin modified, Chung-Pfost modified, and Hasley isotherms and the Henderson model best fitted experimental data. The net isosteric heat of sorption values determined using Clausius-Clapeyron ranged from 3.04 and 0.92kJ/mol between 5% and 30% moisture content in dry basis, respectively. Differential entropy also decreased with moisture content. The compensation theory was applied to sorption isotherms and higher value of isokinetic temperature than harmonic mean temperature denotes that adsorption process was enthalpy controlled and a negative value of Gibbs free energy reflected a spontaneous process.

• 出版日期2015-5-4