Carrots effective diffusivity

Fig. 8.10 Influence of drying temperature on the identified effective diffusivity for carrot drying carried out with and without uitrasound application. From Carci a-Perez et at. p006b).

Fig. 8.11 Identified effective difFusivities of atmospheric freeze drying —14°C, 2ms of carrot, eggplant and apple, with (AIR+ US) and without (AIR) ultrasound application (19.5 kW m , ...

Fig. 8.12 Influence of applied ultrasonic power density on the identified effective diffusivity for the drying of (a) carrot and (b) lemon peel. The bars indicate intervals with a confidence level of 95% (Garcia-Perez et al., 2009).

In order to detect the effect of conditioning on growth, the stimulation of multiplication on carrot cell low-density cultures was utilized as bioassay. Our initial approach has been simply to repeat, with minor modification, the experiments of Street (5) and we confirmed that a CF is a molecule of low molecular weight that can diffuse through a dialysis membrane. 

High-intensity electric field pulses accelerated osmotic dehydration of carrot [18], A Fickian diffusion coefficient for water and solute increased exponentially with electric field strength. This effect was attributed to increased cell wall permeability, which was also manifested by the softening of product. 

The final form of the carrot-like protrusion is shown in Fig. 2.6e. It can be concluded from the parabolic shape that such protrusions grow as moving paraboloids in accordance with the Barton-Bockris theory [5], the tip radius remaining constant because of the surface energy effect. It can be concluded from Fig. 2.6f that thickening of such a protrusion is under mixed activation-diffusion control because the deposit is seen to be of the same quality as that on the surrounding macroelectrode surface. It can be seen from the Fig. 2.6d that activation control takes place only at the very tip of the protrusion. 

M.A. Ruiz - Cabrera, M.A. Salgado-Cervantes, K.N. Waliszewski-Kubiak and M.A. Garcia-Alvarado, The Effect of Path Diffusion on the Effective Moisture Diffusivity in Carrot Slabs, Drying Techn., 15, 1 (1997) 169-181. 

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