TY - JOUR
T1 - Moisture profiles in a model food gel during drying
T2 - Measurement using magnetic resonance imaging and evaluation of the fickian model
AU - Schrader, Greg Warren
AU - Litchfield, J. Bruce
PY - 1992/3/1
Y1 - 1992/3/1
N2 - Magnetic resonance imaging (MRI) was used to obtain moisture profiles of a model food gel during drying. A cylinder of gel, 1 cm in diameter, with an initial moisture content of 76% was imaged while drying at room temperature. Moisture profiles were obtained from the imaging data by imaging calibration samples of known moisture content. Signal intensity of the images was found to be highly proportional to solids content. The moisture profiles were compared to profiles predicted by a finite difference solution of Fickian radial diffusion in a cylinder. Actual moisture profiles obtained by MRI were much flatter near the center of the cylinder, with a steeper moisture profile near the edge, compared to the typical parabolic shape of the Fickian model. The Fickian model was found to be an inaccurate predictor of the interior moisture profile of the model food gel, since effective diffusivity was found to not be solely a function of moisture content. The moisture profiles obtained provide for a method to evaluate other mass transfer models, and the methods outlined provide a technique to explore mass transfer within actual food materials during processing.
AB - Magnetic resonance imaging (MRI) was used to obtain moisture profiles of a model food gel during drying. A cylinder of gel, 1 cm in diameter, with an initial moisture content of 76% was imaged while drying at room temperature. Moisture profiles were obtained from the imaging data by imaging calibration samples of known moisture content. Signal intensity of the images was found to be highly proportional to solids content. The moisture profiles were compared to profiles predicted by a finite difference solution of Fickian radial diffusion in a cylinder. Actual moisture profiles obtained by MRI were much flatter near the center of the cylinder, with a steeper moisture profile near the edge, compared to the typical parabolic shape of the Fickian model. The Fickian model was found to be an inaccurate predictor of the interior moisture profile of the model food gel, since effective diffusivity was found to not be solely a function of moisture content. The moisture profiles obtained provide for a method to evaluate other mass transfer models, and the methods outlined provide a technique to explore mass transfer within actual food materials during processing.
KW - Finite difference
KW - Mass transfer
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U2 - 10.1080/07373939208916440
DO - 10.1080/07373939208916440
M3 - Article
AN - SCOPUS:0026834821
SN - 0737-3937
VL - 10
SP - 295
EP - 332
JO - Drying Technology
JF - Drying Technology
IS - 2
ER -