Study of thermodynamic water properties and moisture sorption hysteresis of mango skin

Food Science and Technology (Campinas)

Silvio José Ferreira De Souza¹  Aline Inácio Alves¹  Érica Nascif Rufino Vieira¹  José Antônio Gomez Vieira¹  Afonso Mota Ramos¹  Javier Telis-romero¹ 

关键词: agricultural waste;    gravimetric method;    integral properties;    modelling;    water content;   

DOI  :  10.1590/1678-457X.6557

来源: SciELO

【 摘 要 】

The equilibrium moisture content for adsorption and desorption isotherms of mango skin was determined using the static gravimetric method at temperatures of 20, 26, 33, 38 and 44 oC in the 0.056 to 0.873 water activity range. Both sorption curves show a decrease in equilibrium moisture content as the temperature increasing. The hysteresis effect was observed at constant water activity. The Guggenheim, Anderson, and de Boer (GAB) model presented the best fitting accuracy among a group of models and was used to determine the thermodynamic properties of water sorption. Integral enthalpy and integral entropy areas showed inverted values for the adsorption and desorption isotherms over the wide range of water activity studied. These values confirm, in energetic terms, the difference between adsorption and desorption isotherms observed in the hysteresis phenomenon. Finally, the Gibbs free energy revealed that the sorption process was spontaneous for both sorption isotherms.

【 授权许可】

CC BY   
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