who found a 32.2% reduction of phenols in thermally-treated apple
juice, while PEF processing (35 kV/cm, 4 ls, 1200 Hz) caused a
14.5% decrease. The total phenolics content of apple and cranberry
juice in the present study did not significantly change after the
application of any of the non-thermal treatments compared to
the untreated control (Table 2). Similarly, the relative TEAC of apple
and cranberry juice, shown in Table 2, was not affected by the
non-thermal processes, whether applied as stand-alone hurdles or
in combination, since the antioxidant activity in apples can be
mostly attributed to their polyphenolic compounds (Eberhardt,
Lee, & Liu, 2000). In a study by Noci et al. (2008) a significant loss
of polyphenolics was observed in fresh apple juice processed by a
batch UV treatment, PEF at 40 kV/cm (n = 100) or a combination
thereof. Although the antioxidant activity of this product decreased
significantly compared to the untreated control, no difference was
found between any of the non-thermally treated samples, with
their mean values being significantly higher (p > 0.05) than the
heat treated sample (94 C for 26 s).