Abstract
Thermal decomposition of cornstarches with different amylose/amylopectin ratios (waxy: 0/100, maize: 23/77, Gelose 50: 50/50, and Gelose 80: 80/20) under nitrogen condition was investigated by thermogravimetric analysis (TGA). Various decomposition models including Friedman, Kissinger, Flynn-Wall-Ozawa, and modified Coast-Redfern methods were used to determine the apparent activation energy of different starches. Fourier transform infrared spectrometry (FTIR) and TGA-FTIR were also used to study the mechanism of thermal decomposition process. The results show a multiple-step mechanism for the thermal decomposition of all cornstarches. The sequence of activation energy for the cornstarches is waxy>maize>G50>G80, which corresponds to amylopectin content. FTIR results confirm that the thermal decomposition of cornstarch is due to the long-chain scission. The higher activation energy for cornstarch with higher amylopectin content can be explained by its higher molecular weight and more α-1,6 bonds.
| Original language | English |
|---|---|
| Pages (from-to) | 139-146 |
| Number of pages | 8 |
| Journal | Starch/Staerke |
| Volume | 62 |
| Issue number | 3-4 |
| DOIs | |
| Publication status | Published - 7 Apr 2010 |
Bibliographical note
Funding informationThe authors from SCUT, China, would like to acknowl-edge the research funds NRDPHT (863) (2007AA10Z312,2007AA100407),GECXYF(2006D90404004),andETRFNK (2006GB2360044). X. Liu would like to knowl-edge the State Scholarship Fund provided by ChinaScholarship Council supports his study in Australia
Keywords
- Activation energy
- Kinetics
- Starch
- Thermal decomposition
ASJC Scopus subject areas
- Food Science
- Organic Chemistry