Vacuum impregnation (VI) is a unit operation in which a porous tissue is immersed in a solution. Vacuum is applied to the system provoking the flow out of the internal air trapped in the extracellular spaces of the tissue. Upon restoration of the atmospheric pressure, the external liquid flows into the pores replacing the air. In this paper, apple pieces were vacuum impregnated with isotonic sucrose solution (18 % w/v) for different times and reduced pressures (15, 30, 45 kPa (abs.)). Using GASMAS (Gas in Scattering Media Absorption Spectroscopy) it was possible to observe that apples, in which air has not been totally exhausted during the impregnation operation, keep an internal reduced pressure which rises slowly toward ambient over a time scale of hours. Both the residual vacuum and the timescale of pressure equilibration with ambient varied with applied vacuum level and apple variety. This phenomenon might be a direct consequence of the topology, geometry and hydrophobicity of the complex matrix of intercellular spaces in the tissue.
Urszula Tylewicz, Patrik Lundin, Lorenzo Cocola, Katarzyna Dymek, Pietro Rocculi, Marco Dalla Rosa, et al. (2012). Pressure Equilibration after Vacuum Impregnation of Apple Tissue Studied by Gas in Scattering Media Absorption Spectroscopy (GASMAS).
Pressure Equilibration after Vacuum Impregnation of Apple Tissue Studied by Gas in Scattering Media Absorption Spectroscopy (GASMAS)
TYLEWICZ, URSZULA;ROCCULI, PIETRO;DALLA ROSA, MARCO;
2012
Abstract
Vacuum impregnation (VI) is a unit operation in which a porous tissue is immersed in a solution. Vacuum is applied to the system provoking the flow out of the internal air trapped in the extracellular spaces of the tissue. Upon restoration of the atmospheric pressure, the external liquid flows into the pores replacing the air. In this paper, apple pieces were vacuum impregnated with isotonic sucrose solution (18 % w/v) for different times and reduced pressures (15, 30, 45 kPa (abs.)). Using GASMAS (Gas in Scattering Media Absorption Spectroscopy) it was possible to observe that apples, in which air has not been totally exhausted during the impregnation operation, keep an internal reduced pressure which rises slowly toward ambient over a time scale of hours. Both the residual vacuum and the timescale of pressure equilibration with ambient varied with applied vacuum level and apple variety. This phenomenon might be a direct consequence of the topology, geometry and hydrophobicity of the complex matrix of intercellular spaces in the tissue.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
