This work aims to study and model the extraction of soluble substances from coffee grounds having different particle sizes. The results demonstrate that coffee brewing cannot be considered a simple diffusion mechanism as reported in the literature. The phenomenon has two phases: a washing phase where surface soluble substances instantaneously dissolve and are transferred to the extract by a convection mechanism, and a diffusion phase involving the solubles within the porous particles. A model was set up to calculate extraction yield as the addition of the two phases. It was also demonstrated that the effect of washing shows a linear correlation with the external surface area of particles and that the composition of the extracts does not depend on extraction time.
|Titolo:||Modelling the acqueous extraction of soluble substances from ground roasted coffee|
|Parole Chiave:||Coffee brew; Extraction kinetics; Modelling|
|Settore Scientifico Disciplinare:||Settore AGR/15 - Scienze e Tecnologie Alimentari|
|Data di pubblicazione:||1992|
|Digital Object Identifier (DOI):||10.1002/jsfa.2740580217|
|Appare nelle tipologie:||01 - Articolo su periodico|