Moisture-Sorption Study of Dried Date Fruits (original) (raw)

The sorption properties of dried date fruits, Khalas and Handal varieties, were studied at 30оC over a range of water activity, 0.10-0.98. A static gravimetric method was adopted and five sorption models: Bradley, BET (Brunauer, Emmet and Teller), Oswin, Henderson, and GAB (Guggenheim, Anderson and de Boer) were used in the analysis. Both Bradley and Henderson models were suitable for the Khalas variety while Oswin and Bradley models better described the behavior of the Handal variety. Monolayer moisture contents (Mo) for the two date fruit varieties were calculated using both the BET and GAB equations and both varieties of date exhibited the BET type II pattern. The monolayer moisture contents for the two varieties were recommended as the least moisture required for stability of dried date fruits in storage.

ANN modeling of water sorption isotherm of date fruits acquired by dynamic vapor sorption

2015

Water sorption isotherms of four Date cultivars at temperatures range of 10 to 80°C with increments of 10°C were determined separately over ranging relative humidity from 10 to 90% using an automatic, gravimetric analyzer. The significant differences in equilibrium moisture contents (EMC) of cultivars can be attributed to chemical composition and structure of each cultivar. The adsorption / desorption experimental data for each cultivar were fitted by modified GAB, modified Halsey, modified Smith and modified Oswin models. The modified Oswin was found as best model to describe adsorption isotherm behavior while modified Halsey was the best model to describe desorption isotherm. In addition, many configurations of artificial neural networks (ANN) were examined to obtain the best one to predict either EMC adsorption isotherm or EMC desorption isotherm for each cultivar. Correlation coefficient (R), c2, root mean square error (RMSE) and relative percent errors (PE) were used to measure...

Loading...

Loading Preview

Sorry, preview is currently unavailable. You can download the paper by clicking the button above.