naa a22 4500 510727115 CHVBK 20180411082939.0 cr unu---uuuuu 180411e20130201xx s 000 0 eng 10.1007/s11947-011-0711-7 doi (NATIONALLICENCE)springer-10.1007/s11947-011-0711-7 Validation of a Difussion Model Using Moisture Profiles Measured by Means of TD-NMR in Apples ( Malus domestica ) [Elektronische Daten] [Óscar Rodríguez, Valeria Eim, Susana Simal, Antoni Femenia, Carmen Rosselló] Time domain nuclear magnetic resonance has been used to obtain experimental moisture profiles of apples during convective drying. The drying curves obtained at temperatures of 50°C, 60°C, 70°C, 80°C and 90°C during convective drying have been modelled using a diffusion model, solved by a finite elements method. The parametric identification was carried out by comparing the experimental and simulated drying curves, and the validation of the model was conducted by comparing the experimental and the simulated moisture profiles. The proposed diffusion model including solid shrinkage and temperature influence on the diffusion coefficient allowed an adequate prediction of not only the drying curves (MRE = 5.4 ± 0.8%) but also the moisture profiles (MRE = 11.0 ± 1.7%). These results support the hypotheses admitted to formulate the mathematical equations of the model and demonstrate the usefulness of this methodology to validate the proposed model. Springer Science+Business Media, LLC, 2011 Time domain-NMR nationallicence Moisture profiles nationallicence Diffusion model nationallicence Apple nationallicence A r : Rectangular face area (m2 nationallicence Eq.2) nationallicence A s : Square face area (m2 nationallicence Eq.1) nationallicence a w : Water activity (Eq.8) nationallicence C 0 : Entropic accommodation factor (Eq.9) dimensionless nationallicence C g : Guggenheim constant (Eq.8) nationallicence D 0 : Pre-exponential factor (m2/s nationallicence Eq.4) nationallicence D e : Effective diffusion coefficient (m2/s nationallicence Eq.3) nationallicence e 1 : Short thickness (m nationallicence Eq.1) nationallicence e 2 : Long thickness (m nationallicence Eq.2) nationallicence e 2 0 : Initial long thickness (m nationallicence Eq.7) nationallicence E a : Activation energy (J/mol nationallicence Eq.4) nationallicence ΔH 1 : Difference between the heats of sorption of the monolayer and the multilayer of water (J/mol nationallicence Eq.9) nationallicence ΔH 2 : Difference between the vaporisation heat of water and the sorption heat of the multilayer of water (J/mol nationallicence Eq.10) nationallicence K 0 : Entropic accommodation factor (Eq.10) nationallicence K g : Constant in the GAB model (Eq.8) nationallicence L : Half length of the parallelepiped (m) nationallicence MRE : Mean relative error (%) nationallicence M : Moisture content (kg water/kg wm) nationallicence N : Number of samples (Eq.6) nationallicence R : Universal gas constant (J/molK nationallicence Eq.4) nationallicence RH : Relative humidity (%) nationallicence RMSE : Root mean square error nationallicence r 2 : Correlation coefficient nationallicence SE : Standard error nationallicence S y : Standard deviation (sample nationallicence Eq.5) nationallicence S yx : Standard deviation (estimation nationallicence Eq.5) nationallicence T : Temperature (°C) nationallicence t : Time (s) nationallicence V c : Calculated value (Eq.6) nationallicence V e : Experimental value (Eq.6) nationallicence var : Explained variance (%) nationallicence W : Average moisture content (kgwater/kgdm) nationallicence W e : Equilibrium moisture content (kgwater/kgdm) nationallicence W m : Monolayer moisture content (kgwater/kgdm nationallicence Eq.8) nationallicence W l : Local moisture content (kg water/kgdm) (Eq.3) nationallicence x : Distance (m) nationallicence δ : Nominal length dimensionless nationallicence Rodríguez Óscar Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut Eim Valeria Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut Simal Susana Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut Femenia Antoni Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut Rosselló Carmen Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut Food and Bioprocess Technology Springer-Verlag 6/2(2013-02-01), 542-552 1935-5130 6:2<542 2013 6 11947 https://doi.org/10.1007/s11947-011-0711-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11947-011-0711-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rodríguez Óscar Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut NATIONALLICENCE 700 1- Eim Valeria Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut NATIONALLICENCE 700 1- Simal Susana Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut NATIONALLICENCE 700 1- Femenia Antoni Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut NATIONALLICENCE 700 1- Rosselló Carmen Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain aut NATIONALLICENCE 773 0- Food and Bioprocess Technology Springer-Verlag 6/2(2013-02-01), 542-552 1935-5130 6:2<542 2013 6 11947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer