Modeling of Moisture Adsorption Isotherm of Selected Commercial flours of Bangladesh

Abstract

The moisture adsorption behavior is a fundamental knowledge in the processing and storage of food materials. In this paper, the experimental adsorption behavior of wheat, rice and corn flours were compared with five widely recommended adsorption models (BET, GAB, Oswin, Smith and Halsey) in the literature. From the sorption data, monolayer moisture content of wheat, rice and corn flours were estimated as per BET and GAB models. For all flours, GAB model gave higher monolayer moisture content compare to the BET model. Linear regression analysis was done to determine the model constants where all models were compared using regression coefficient and standard error of the estimate. It was observed that there is no single model that could describe accurately the sorption isotherm over the whole range of water activity (a w ) and for all types of flours. BET model was found as the best model for the prediction of equilibrium moisture content (EMC) of the most stable region (i.e. EMC corresponding to a w range below 0.52) but it was not suitable at a w above 0.52. The GAB model was found to be the most suitable to predict the EMC for wide range of water activity (0.11 to 0.93).

Experimental Investigation of Moisture Sorption Isotherms for Mefenamic Acid Tablets

“…Changes occur when the moisture content value of a product is lower than M w [1,22]. It is generally decreased with temperature and that agreed with [7,23,27]. The estimated values of %Mm on a dry basis using the GAB model are presented in Table 5.…”

“…There are two equilibrium moisture contents at constant air relative humidity and temperature depending on the experimental conditions, whether the moisture content of the material is higher or lower than the equilibrium for environmental conditions (desorption or adsorption) [6,7].…”

Moisture adsorption isotherms of baru almond flours

“…In addition to the oil content factor, the parameter X m may also have been influenced by the estimation by different models. Ahmed et al (2018) studying the adsorption isotherms of wheat, rice and corn flours found that the GAB model provided higher values for moisture in the molecular monolayer than that of BET. However, this fact will denounce the product characteristics.…”

“…Among the models and equations can be cited those proposed by Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de-Boer (GAB) (Peleg, 2020). The hygroscopic behavior of many food and agricultural products has been explained by these two models (Bastıoğlu et al, 2017;Ahmed et al, 2018;Jung et al, 2018;Xu et al, 2019).…”

Moisture sorption and thermodynamic properties of Camellia oleifera seeds as influenced by oil content

“…Further analysis of sorption behavior by the application of thermodynamic principles can exhibit important information that provides an understanding of moisture properties and associated energy requirements of heat and mass transfer, food physicochemical and microbiological stability [10,11] . Thermodynamic parameters such as differential enthalpy and entropy, integral enthalpy and entropy, equilibrium spreading pressure, binding energy, sorption activity and average capacity per unit mass have been studied individually or jointly in previous reports of walnut [12] , chestnut [13] , peanut [14] , Zanthoxylum bungeanum seeds [15] and wheat [16,17] .…”