ISSN:
1365-2621
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
The apparent diffusion coefficients (D J for total solute loss from cylinders of Chantenay carrot cortex tissue were calculated after blanching under various conditions. Cell sap concentration was measured before and after blanching for times up to 1800 sec, in the temperature range 333-363°K. Values of D, were found to be in the range 3×10-10-8-10-′0m2/sec, and could be related to temperature by an Arrhenius type equation, having an activation energy of 28.2 kJ/mol. D, was independent of cylinder diameter between 0.005 and 0.007 m, but appeared to increase in blanch media concentrations that were higher than the initial carrot cell sap concentration. The formal numerical solutions for unsteady state diffusion mass transfer were recalculated in the relevant cell sap concentration range (7.8-10.4% as sucrose), and are given in tabular form for the shapes of slab of infinite extent, sphere, and cylinder of infinite length. In design, these results will allow the prediction of mean cell sap concentration, and hence the overall losses incurred, after a given blanch or wash treatment in this time and temperature range.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2621.1983.tb00285.x
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