Effects of Blanching on the Antioxidant Content
of Cabbage
A number of studies have investigated the effect of
blanching on the polyphenolic content of cabbage (Table
5.1). Different effects have been reported depending on
differences in process conditions and systems applied in the blanching process. A detailed study was carried out
by Jaiswal et al. (2012c) to evaluate the effect of conventional
water blanching on the polyphenols of York cabbage.
A range of blanching temperatures (80, 85, 90, 95,
and 100°C) for 0–14min with a 2min interval was studied
with the aim of including both low and high blanching
temperatures (Figure 5.1). Reductions in the total phenolic
content up to 45% were reported at the lower blanching
temperatures (80–90°C) within 2min of blanching
and reached up to 50% at high blanching temperatures
(95–100°C) for the same blanching period of 2min. Degradation
in total phenolic content continued up to 76%
within 6min at high blanching temperatures; however,
no significant reductions in total phenolic content were
reported after this for up to 14min, a stage at which the
cabbage was considered to be completely processed.
(Figure 5.1a). Jaiswal et al. (2012c) also reported similar
observations for the effects of blanching time on the
degradation of total flavonoid content of York cabbage
(Figure 5.1b). These findings highlight the deleterious
effects of blanching in compromising the significance of
cabbage in being one of the richest vegetable sources of
antioxidants.