CIDCA   05380
CENTRO DE INVESTIGACION Y DESARROLLO EN CRIOTECNOLOGIA DE ALIMENTOS
Unidad Ejecutora - UE
artículos
Título:
Mathematical modeling and simulation of microwave thawing of large solid foods under different operating conditions
Autor/es:
CAMPAÑONE L; ZARITZKY N
Revista:
FOOD AND BIOPROCESS TECHNOLOGY
Editorial:
SPRINGER
Referencias:
Año: 2009 p. 1 - 33
ISSN:
1935-5130
Resumen:
Microwaves require shorter times to increase foodstuffs
temperature when compared to conventional heating
methods. However, there are some problems associated to
temperature distribution within the products, owing to the
preferential absorption of electromagnetic energy by liquid
water, caused by differences between its dielectric properties
and those of ice (runaway). To analyze the behavior of food
microwave thawing, a mathematical three-dimensional (3D)
model was developed by solving the unsteady-state heat and
mass transfer differential equations; this model can be applied
to large systems for which Lamberts law is valid. Thermal,
mass transport, and electromagnetic properties varying with
temperature were used. The numerical solution was developed
using an implicit CrankNicolson finite difference method
using the classical formulation for one-dimensional (1D)
systems and the alternating direction method in two and three
dimensions. The model was validated using experimental data
from the literature for 1D and two-dimensional conditions and
with experiments performed in our laboratory for 3D heat
transfer using frozen meat. It was applied to predict temperature
and water concentration profiles under different thawing
conditions in meat products and to simulate the effect of a fat
layer located at the surface of the meat piece on temperature
profiles. For different product sizes in rectangular geometry,
numerical simulations demonstrated that microwave thawing
times were significantly lower in comparison to conventional
thawing methods. To prevent overheating during thawing, the
combination of continuous microwave power with simultaneous
application of air convection and the application of
microwave power cycles, using refrigerated air convection
with controlled surface temperature, were analyzed.runaway). To analyze the behavior of food
microwave thawing, a mathematical three-dimensional (3D)
model was developed by solving the unsteady-state heat and
mass transfer differential equations; this model can be applied
to large systems for which Lamberts law is valid. Thermal,
mass transport, and electromagnetic properties varying with
temperature were used. The numerical solution was developed
using an implicit CrankNicolson finite difference method
using the classical formulation for one-dimensional (1D)
systems and the alternating direction method in two and three
dimensions. The model was validated using experimental data
from the literature for 1D and two-dimensional conditions and
with experiments performed in our laboratory for 3D heat
transfer using frozen meat. It was applied to predict temperature
and water concentration profiles under different thawing
conditions in meat products and to simulate the effect of a fat
layer located at the surface of the meat piece on temperature
profiles. For different product sizes in rectangular geometry,
numerical simulations demonstrated that microwave thawing
times were significantly lower in comparison to conventional
thawing methods. To prevent overheating during thawing, the
combination of continuous microwave power with simultaneous
application of air convection and the application of
microwave power cycles, using refrigerated air convection
with controlled surface temperature, were analyzed.s law is valid. Thermal,
mass transport, and electromagnetic properties varying with
temperature were used. The numerical solution was developed
using an implicit CrankNicolson finite difference method
using the classical formulation for one-dimensional (1D)
systems and the alternating direction method in two and three
dimensions. The model was validated using experimental data
from the literature for 1D and two-dimensional conditions and
with experiments performed in our laboratory for 3D heat
transfer using frozen meat. It was applied to predict temperature
and water concentration profiles under different thawing
conditions in meat products and to simulate the effect of a fat
layer located at the surface of the meat piece on temperature
profiles. For different product sizes in rectangular geometry,
numerical simulations demonstrated that microwave thawing
times were significantly lower in comparison to conventional
thawing methods. To prevent overheating during thawing, the
combination of continuous microwave power with simultaneous
application of air convection and the application of
microwave power cycles, using refrigerated air convection
with controlled surface temperature, were analyzed.Nicolson finite difference method
using the classical formulation for one-dimensional (1D)
systems and the alternating direction method in two and three
dimensions. The model was validated using experimental data
from the literature for 1D and two-dimensional conditions and
with experiments performed in our laboratory for 3D heat
transfer using frozen meat. It was applied to predict temperature
and water concentration profiles under different thawing
conditions in meat products and to simulate the effect of a fat
layer located at the surface of the meat piece on temperature
profiles. For different product sizes in rectangular geometry,
numerical simulations demonstrated that microwave thawing
times were significantly lower in comparison to conventional
thawing methods. To prevent overheating during thawing, the
combination of continuous microwave power with simultaneous
application of air convection and the application of
microwave power cycles, using refrigerated air convection
with controlled surface temperature, were analyzed.