3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
standard of β-carotene that was dissolved in ethanol. Fig. 2.
shows calibration curve of a standard β-carotene.
The regression equation was obtained from the calibration
curve of β-carotene, y = 0.3026 x + 10.353 (R 2 = 0.9904).
This studied range was appropriate to calculate concentration
of β-carotene in tomatoes.
The small peak showing the β-carotene on Fig. 3. (very
closely at 2.912 min) has not been identified, because it is an
admissive peak area that matches β-carotene’s peak in chromatograms.
Fig. 3. Chromatograms from tomato extract
However, this does not pose any problem; usually tomatoes
do not contain high concentration of β-carotene. Result
of this chromatogram suggests the presence of other organic
compounds in tomato. Many study indicated that lycopene
and/or other common cartenoids’s levels are higher than βcarotene
in tomatoes.
Table I shows the results obtained from the analysis of
β-carotene in different samples. The first sample was immediately
extracted with extraction solution after purchased
from supermarket. The second sample was stored 2 weeks in
a refrigerator before extraction.
The higher value of β-carotene (1.197 mg 100 g –1 ) was
obtained with the first sample. The values obtained in this
s578
Table I
Tomato concentration of β-carotene
Sample Weight Peak area Amount of β-carotene
[g] [mV s –1 ] [mg 100 g –1 of fresh mass]
1 10.0707 14.0 1.197
2 10.1726 1.6 0.024
study are very close to those reported by Olives Barba et al. 3 ,
who reported a range of 0.6–1.2 mg per 100 g for β-carotene
in 4 tomato varieties.
Bender (1993) has summarised the contradictory results
of published studies designed to estimate the magnitude of
vitamin loss during frozen storage of vegetables and fruits.
Thus, we presumed that the content of β-carotene was reduced
in second sample during storage period.
Conclusions
The present study shows that the measured levels of
β-carotene (1.197 mg 100 g –1 ) were low compared to the
recommended intake. European epidemiological studies
revealed 6–10 mg β-carotene as the recommended daily
intake to provide good health and a reduction in risk of diseases
(Lachance, 1998; national Research Council, 1989).
Accordingly, one serving 100 g tested tomato contributes
11.97–19.95 % of the recommended daily intake of β-carotene.
REFEREnCES
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3. Olives Barba. A. I., Camara Hurtado M., Sanchez Mata
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