Thermal Food Processing

464 Thermal Food Processing: New Technologies and Quality Issues
Voltage gradient (V)
β(εf) Fraction of heat transfer by conduction through the mixture in
the fluid phase (–)
εf Fluid volume fraction in the heater (–)
εp Volume fraction (–)
ρf Fluid density (kg·m –3 )
ρp Particle density (kg·m –3 )
σ0f Electrical conductivity of the fluid before the heating takes
place (S·m –1 )
σ0p Electrical conductivity of the particle before the heating takes
place (S·m –1 )
σeff Effective electrical conductivity (S·m –1 )
σref Electrical conductivity at a reference temperature (S·m –1 )
σT Electrical conductivity at temperature T (S·m –1 )
σx Electrical conductivity in the x direction (S·m –1 )
σy Electrical conductivity in the y direction (S·m –1 )
σ Electrical conductivity (S·m –1 ∇V
)
ALP Alkaline phosphatase
b-GAL β-Galactosidase
LOX Lipoxygenase
OH Ohmic heating
PEC Pectinase
PPO Polyphenoloxidase
REFERENCES
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