Format

Send to

Choose Destination
Food Chem. 2014 Jul 15;155:81-6. doi: 10.1016/j.foodchem.2014.01.034. Epub 2014 Jan 23.

Thermal degradation kinetics study of curcumin with nonlinear methods.

Author information

1
Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, China.
2
Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, China. Electronic address: liaosen@gxu.edu.cn.
3
Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, China; School of Materials Science and Engineering, Guangxi University, Nanning, Guangxi 530004, China.

Abstract

The results of TG/DTG when curcumin was used as the food colouring agent indicated that the processing temperature of the food should not exceed 190°C. The decomposition process of curcumin involved two stages. The results of Eα values, determined by an advanced isoconversional method, showed that the two stages were both single-step processes. The most probable mechanisms of the two stages were estimated by using comparative and nonlinear model-fitting methods. The mechanisms obtained from the two methods are the same, which are the assumed random nucleation and its subsequent growth for stage I and one-dimensional diffusion for stage II, respectively. The values of pre-exponential factor A for both stages were obtained on the basis of Ea and g(α). Besides, some thermodynamic functions (ΔS(≠), ΔH(≠) and ΔG(≠)) of the transition state complexes for the two stages were also calculated.

KEYWORDS:

Activation energy; Advanced isoconversional method; Curcumin; Kinetic analysis; Thermogravimetric analysis

PMID:
24594157
DOI:
10.1016/j.foodchem.2014.01.034
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center