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Composition of tomatoes and tomato products in antioxidants (WG1) page 60
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As an example of sensitivity to oxygen, Black (1998) has measured the decrease in
absorbance of a solution of carotenoid in hexane when bubbled with oxygen. In these
experimental conditions, lycopene is shown to be more sensitive to degradation than β-
carotene (figure 6).
Absorbance
1,1
1,0
0,9
0,8
0,7
0,6
0 10 20 30 40 50 60
Figure 6 : Decrease in absorbance of a solution of carotenoid in hexane
when bubbled with oxygen with ■ : β-carotene ; ○ : lycopene
Sharma and Le Maguer (1996a) have followed the time-dependent loss of lycopene in
tomato pulp when heated at 100°C ( figure 7)
Lycopene (mg/100g
total solids)
200
190
180
170
160
150
Time (min)
0 20 40 60 80 100 120 140
Time (min)
Figure 7 : Kinetics of lycopene degradation in tomato pulp heated at 100°C