The PEF apparatus consisted of a pu

The PEF apparatus consisted of a pulsed high voltage power
supply (Tomsk Polytechnic University, Tomsk, Russia) and a batch
one-liter treatment chamber with stainless electrodes (Fig. 1a). The
electrodes of the treatment chamber were two parallel disks. The
electrode area was 95 cm2. The circuit configuration and the electrodes
shape generated exponential decay pulses. The PEF pulse
length was about ti ¼ 10 ms.
Grape seeds (50.0  0.1 g) were introduced between the electrodes.
Extraction solvent at 20
C or 50
C was then added to the
solid. The liquid-to-solid ratio (w/w) was 5. The liquid was either
distilled water or an aqueous mixture with up to 50 g EtOH/100 g S.
The initial electrical conductivity of the suspension ranged from 300
to 500 mS/cm. A positive pulse voltage was applied to the needle
electrode. The high voltage pulse generator provided 40 kVe10 kA
pulses. The distance between electrodes was fixed at 2, 3, 4 and 5 cm.