Gas in Scattering Media Absorption Spectroscopy (GASMAS) Detected Persistent Vacuum in Apple Tissue After Vacuum Impregnation
Food Biophysics - 2011
Tóm tắt
The microstructure and the capillary pressure of the pore space are important variables for better understanding of the complex phenomena occurring during vacuum impregnation (VI) of plant tissues. In this study, we used GASMAS (Gas in Scattering Media Absorption Spectroscopy) of oxygen to, non-destructively, measure the dynamics of the internal pressure in apple pieces after restoration of the atmospheric pressure. Apple pieces were impregnated with isotonic sucrose solution (18% w/v) at different reduced pressures (15, 30, 45 kPa (abs.)). After restoration of the atmospheric pressure, the pressure of the remaining pore space gas could remain as low as 50 kPa (abs) and rise 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. It is proposed that at least a part of the pore space of apples may be hydrophobic, giving rise to a negative Laplace pressure, and thus the convective flow of impregnating solution is arrested at a mechanical equilibrium where internal pressure is lower than external pressure. Further pressure equilibration can then only be achieved either by gas diffusion in gas phase, or by gradual wetting of the pores.
Từ khóa
Tài liệu tham khảo
M.L. Gras, D. Vidal, N. Betoret, A. Chiralt, P. Fito, Calcium fortification of vegetables by vacuum impregnation. Interactions with cellular matrix. J. Food Eng. 56, 279–284 (2003)
P. Fito, A. Chiralt, N. Betoret, M. Gras, M. Cháfer, J. Martínez-Monzóeering, Application in functional fresh food development. J. Food Eng. 49(2–3), 175–183 (2001)
P.Y. Phoon, F. Gómez Galindo, A. Vicente, P. Dejmek, Pulsed electric field in combination with vacuum impregnation with trehalose improves the freezing tolerance of spinach leaves. J. Food Eng. 88, 144–148 (2008)
E. Velickova, U. Tylewicz, M. Dalla Rosa, E. Winkelhausen, S. Kuzmanova, F. Gómez Galindo, Effect of vacuum infused cryoprotectants on the freezing tolerance of strawberry tissues. LWT Food Science and Technology. In press
P. Fito, Modelling of vacuum osmotic dehydration of food. J. Food Eng. 22, 313–328 (1994)
P. Fito, R. Pastor, Non-diffusional mechanisms occurring during vacuum osmotic dehydration. J. Food Eng. 21, 513–519 (1994)
P. Fito, A. Andrés, A. Chiralt, P. Pardo, Coupling of hydrodynamic mechanism and deformation-relaxation phenomena during vacuum treatments in solid porous food-liquid systems. J. Food Eng. 27, 229–240 (1996)
D. Salvatori, A. Andrés, A. Chiralt, P. Fito, The response of some properties of fruit to vacuum impregnation. J. Food Process Eng. 21, 59–73 (1998)
M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, S. Svanberg, Analysis of gas dispersed in scattering media. Opt. Lett. 26, 16–18 (2001)
G. Somesfalean, M. Sjöholm, J. Alnis, C. af Klinteberg, S. Andersson-Engels, S. Svanberg, Concentration measurement of gas embedded in scattering media by employing absorption and time-resolved laser spectroscopy. Appl. Opt. 41, 3538–3544 (2002)
S. Svanberg, Analysis of trapped gas—gas in scattering media absorption spectroscopy. Laser Phys. 20, 68–77 (2010)
M. Andersson, L. Persson, M. Sjöholm, S. Svanberg, Spectroscopic studies of wood-drying processes. Opt. Express 14, 3641–3653 (2006)
L. Persson, M. Andersson, T. Svensson, M. Cassel-Engquist, K. Svanberg, S. Svanberg, Non-intrusive optical study of gas and its exchange in human maxillary sinuses, in Proceeding of SPIE-OSA Biomedical Optics 6628, Art. ID: 662804 (2007)
T. Svensson, L. Persson, M. Andersson, S. Svanberg, S. Andersson-Engels, J. Johansson, S. Folestad, Noninvasive characterization of pharmaceutical solids by diode laser oxygen spectroscopy. Appl. Spectrosc. 61, 784–786 (2007)
M. Lewander, Z.G. Guan, L. Persson, A. Olsson, S. Svanberg, Food monitoring based on diode laser gas spectroscopy. Appl. Phys. B 93, 619–625 (2008)
M. Lewander, P. Lundin, T. Svensson, S. Svanberg, A. Olsson, Non-intrusive measurements of headspace gas composition in liquid food packages made of translucent materials. Packag. Technol. Sci. 24(5), 271–280 (2011)
L. Persson, B. Anderson, M. Andersson, M. Sjöholm, S. Svanberg, Studies of Gas Exchange in Fruits Using Laser Spectroscopic Techniques. Information and Technology for Sustainable Fruit and Vegetable Production FRUTIC 05, 12–16 September, Montpellier France (2005)
L. Persson, H. Gao, M. Sjöholm, S. Svanberg, Diode laser absorption spectroscopy for studies of gas exchange in fruits. Opt. Lasers Eng. 44, 687–698 (2006)
M. Gras, D. Vidal-Brotόns, N. Betoret, A. Chiralt, P. Fito, The response of some vegetables to vacuum impregnation. Innov. Food Sci. Emerg. Technol. 3, 263–269 (2002)
R.A. Baker, L. Wicker, Current and potential applications of enzyme infusion in the food industry. Trends Food Sci. Technol. 7, 279–284 (1996)
K. Esau, Anatomy of seed plants (Wiley, New York, 1977)
F. Mendoza, P. Verboven, H.K. Mebatsion, G. Kerckhofs, M. Wevers, B. Nicolai, Three-dimensional pore space quantification of apple tissue using X-ray computed microtomography. Planta 226, 559–570 (2007)
P. Fito, A. Chiralt, in Vacuum impregnation of plant tissues in minimally processed fruits and vegetables: fundamental aspects and applications, ed, by S.M. Alzamora, M.S. Tapia, A. López-Malo (Springer, 2000), pp. 189–202
A.A. Khan, J.F.V. Vincent, Anisotropy of apple parenchyma. J. Sci. Food Agric. 52, 455–466 (1990)