Starch thermal analysis

Morita, H. (1956a). Characterization of starch and related polysaccharides by differential thermal analysis. Anal. Chem. 28, 64-67. 

Shiotsubo, T. and Takahashi, K. (1984). Differential thermal analysis of potato starch gelatinization. Agric. Biol. Chem. 48, 9-17. 

Wada, K., Takahashi, K., Shirai, K., and Kawamura, A. (1979). Differential thermal analysis (DTA) applied to examining gelatinization of starches in foods. Journal of Food Science. 44, 1366-1372. 

Liu, Q., Lu, X., Yada, R. (2005). The effect of various potato cultivars at different times during growth on starch content determined by differential scanning calorimetry. Journal of Thermal Analysis and Calorimetry, 79(1), 13-18. 

Tarvainen et al. (2002) studied the film-forming ability of starch acetate (DS 2.8) and the effect of commotfly used plasticizers on the physical properties of starch acetate films. The properties were compared with ethylcellulose films. Mechanical studies, water vapor and drug permeability tests, and thermal analysis by differential scarming calorimetry (DSC) were used to characterize the film-forming ability of starch acetate and efficiency of tested plasticizers. Starch acetate films were foimd to be tougher and stronger than ethylcellulose films at the same plasticizer concentration. Also, in most cases, the water vapor permeability of starch acetate... 

The compression of starch in the presence of some mineral salts (CoCl2 and FeCl3) and of elemental iodine leads to the formation of starch-additive inclusion complexes. Among many salts tested, some form only physical mixtures, as proved by thermal analysis.63,64 (See Appendix for additional text.)... 

Lelievre, J. (1992). Thermal analysis of carbohydrates as illustrated by aqueous starch systems. In Developments in Carbohydrate Chemistry, Alexander, R. J., and Zobel, H. F. (Eds.), pp. 137-161. Amer. Assoc. Cereal Chem., St. Paul, MN. 

Differential Thermal Analysis (DTA), Thermogravimetric Analysis (TGA), and Differential Thermogravimetric Analysis (DTG) of Potato Starch Dried by Three Methods (All Temperatures in °C)3SS... 

The addition of various salts to potato starch on its compression up to 1.2 X 109 Pa had only a small effect on the thermal properties of starch, as measured by thermogravimetry/differential thermogravimetry/differential thermal analysis (TG/DTG/DTA). Only FeCl3, CoCl2, and I2 caused significant effects.62... 

As with pyridine, N,N -dimethylformamide significantly affects the characteristics of gelation of potato starch. Based on thermal analysis, there is a suggestion that a reaction may occur between starch and that amide683,684 on 3 h of conditioning at 100 °C. 

Thermal analysis has also been used to characterize the structure of starch. A melting endotherm due to the crystalline portions of starch has been investigated, but it is not clearly resolved in all samples due to the small amount of crystalline material present in the samples. This transition is also dependent on the sample preparation and moisture content of the material. Melting points of 168-210°C have been reported. The glass transition temperature (Tg) in starch, measured using differential scanning calorimetry (DSC), was found to be dependent on the moisture content... 

Results of Differential Thermal Analysis of Starches of Varions Origins... 

New physicochemical techniques have now become available for studying thermal reactions these include differential thermal analysis and thermogravimetric analysis. These techniques have been applied in studying the pyrolysis of starch. 

In differential thermal analysis, the starch is intimately mixed with a thermally inert materiaP such as calcined kaolin or alumina the mixture is heated at a uniform rate, and the temperature of the mixture is compared with that of a sample of the pure, inert material heated in the identical manner. Any exothermic or endothermic reaction in the starch causes a positive or negative temperature-difference between the two samples this can be recorded, and appears as a positive or negative peak on the resultant thermogram. Differential thermal analysis can be conducted in different atmospheres, such as air, oxygen, or nitrogen, or under vacuum. 

The results of the work of various authors on the differential, thermal analysis of granular starch are shown in Table I. It may be seen that agreement between the results is poor, and that the temperatures at which exo- or endo-thermic reactions occur for starch are not yet known with any useful degree of certainty. Some results have been obtained with the... 

It appears that, in investigating the pyrolysis of starch, more careful and extensive use should be made of recent physical techniques for studying the thermal analysis of polymers. Under the well-controlled conditions necessary, these techniques should yield invaluable information concerning the characteristics of the thermal reactions involved in the degradation of starch. 

Previous articles in this Series dealt with etherifications of cellulose, and an atlas on infrared analysis includes spectral data for various cellulose ethers. The preparation and industrial importance of starch ethers have been reviewed. The degree of substitution of cellulose ethers may be determined by differential thermal analysis. Where an endothermic or exothermic peak that is characteristic of the cellulose derivative occurs in the analysis curve, the peak height and area have been shown to correlate with the degree of substitution. 

Differential thermal analysis has been applied to an examination of the thermal behaviour of starch and foodstuffs. Potato starch showed an endotherm at ca. 65 C which was not influenced by either the rate of heating, or the concentration and the initial amount of starch. Similar analyses, applied to intact potato, Indian lotus, taro, and sweet potato, were distinct from each other but were similar to the starch from each plant except that the isotherm was shifted by 3-7 °C to the higher temperature region. ... 

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