G. Leach et al., EFFECTIVE DIFFUSIVITY OF TOTAL SOLIDS AND PECTIC SUBSTANCES FROM APPLE TISSUE, International journal of food science & technology, 29(6), 1994, pp. 687-697
The effective diffusivities of total solids and pectic substances from
apple tissue were determined at 40 and 60 degrees C in water and buff
er; the addition of pectolytic enzyme in buffer at 40 degrees C was al
so investigated. The Fickian model for unsteady-state diffusion was ap
plicable in all cases. Effective diffusivity values both for total sol
ids and soluble pectic substances in deionized water were temperature
dependent. The effective diffusivity values for total solids loss were
reduced by the presence of buffer at 40 degrees C but not at 60 degre
es C. The effective diffusivity values for soluble pectic substances w
ere not affected by buffer at 40 degrees C but were noticeably lower a
t 60 degrees C compared to deionized water at the same temperature. Th
e addition of a pectolytic enzyme preparation did not improve the mass
transfer of either total solids or soluble pectic substances.