Title |
HPLC INVESTIGATION OF THE DEGRADATION OF SOME ARTIFICIAL AZO FOOD COLORANTS IN THE PRESENCE OF ASCORBIC ACID |
Author/s |
Vesna Kostić, Trajče Stafilov, Kiro Stojanoski |
Citation |
V. Kostić, T. Stafilov and K. Stojanoski, "HPLC INVESTIGATION OF THE DEGRADATION OF SOME ARTIFICIAL AZO FOOD COLORANTS IN THE PRESENCE OF ASCORBIC ACID", Contributions, Sec. Math. Tech. Sci., MASA, ISSN 0351–3246, Vol. 29, no.1-2, 2008, pp.89-98. |
Abstract |
The influence of the concentration of ascorbic acid
on some azo food colorant (Brilliant Black BN, Brilliant Blue
FCF, Chinoline Yellow, Indigotine, Patent Blue V and Tartazine)
degradation in the solution has been studied. Rate constant (k),
time of colorant half-life (t1/2), as well as the type of the kinetic
reaction have been determined. The colorants and the ascorbic
acid have been determined by high performance liquid
chromatography (HPLC) with diode array detector (DAD) and
UV-VIS spectrometry. It was found that the higher concentration
of ascorbic acid leads to the higher rate constant and lower
colorants half-life. The values of the rate constants are 2.50–4.25
times higher when the colorant degradation was run in the
presence of 500 mg L–1 of ascorbic acid than in the case of the
presence of 100 mg L–1 ascorbic acid for Brilliant Blue FCF,
Chinoline Yellow, Patent Blue V and Tartazine. From the other
side, the degradation of Brilliant Black BN and Indigotine is very
fast with a total degradation for 6–9 days. Therefore, the rate
constants for those two food colorants are much higher than for
the other investigated colorants. According to the linearity of the
kinetics curves (ln(c/co) v.s. time) it appeared to be first order
kinetics for the interval up to 4 days.
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Keywords |
Food Colorants; Brilliant Black BN; Brilliant Blue
FCF; Chinoline Yellow; Indigotine; Patent Blue V; Tartazine;
ascorbic acid; degradation; kinetics rate constant; HPLC; UV-VIS spectrometry |