3.4. Impact of HP and HPHT processing on chlorophylls in green
vegetables
Chlorophyll content of raw green vegetables is shown in Table 2.
Data are similar to those reported by other authors (Kaur &
Manjrekar, 1975). The ratio chlorophyll a: chlorophyll b was
2.8:1, 2.7:1 and 2:1 for broccoli, spinach and green pepper, respectively.
Similar ratios have been reported for these green vegetables
(Van Loey et al., 1998).
Fig. 3 shows the relative chlorophylls content (%) after HP and
HPHT treatments at different temperatures. No significant chlorophylls
degradation was found after the HP treatment at 20 C
(625 MPa, 5 min) whatever green vegetable tested. On the contrary,
a significant increase of chlorophyll b in broccoli and spinach
was observed. Similarly, a significant rise of chlorophyll a was also
pointed out for HP treated spinach. Absence of chlorophyll