enzyme-inactivation of orange juice and gazpacho. Min,
Jin, Min, et al. (2003a) reported no differences between
fresh orange juice and HIPEF-treated orange juice when
they processed orange juice at 40 kV/cm for 97 ls at
2000 Hz with bipolar pulses of 2.6 ls and a maximum
temperature of 45 C. On the other hand, after processing
orange juice by HIPEF with bipolar pulses of 4 ls
at 800 Hz and 35 kV/cm during 750 ls (maximum temperature
of 50 C), a vitamin C retention of 93% was
observed (Sa´nchez-Moreno et al., 2005). Evrendilek
et al. (2000) reported that HIPEF-processing of apple
juice did not alter the natural vitamin C of the juice
(35 kV/cm, 94 ls, 952 Hz, monopolar pulses of 1.92 ls,
maximum temperature 38 C). Min et al. (2003b) did
not observed differences in vitamin C retention between
fresh and HIPEF-processed tomato juice at 40 kV/cm
for 57 ls with bipolar pulses of 2 ls and a maximum
temperature of 45 C. All of these studies were performed
by keeping constant the HIPEF treatment conditions.
However, no information about the effect of
HIPEF-processing parameters on vitamin C content in
foods was found in the literature.