TY - JOUR
T1 - Immersion mode material pocket dynamic mechanical analysis (IMP-DMA): A novel tool to study gelatinisation of purified starches and starch-containing plant materials
AU - Warren, Frederick J.
AU - Royall, Paul
AU - Butterworth, Peter J.
AU - Ellis, Peter R.
PY - 2012/9/1
Y1 - 2012/9/1
N2 - There is a clear need for improved methods for the study of the physical changes that occur in slurries and sol-gel systems that have significant water content. In this paper a novel immersion mode material pocket form of dynamic mechanical analysis (IMP-DMA) has been designed, combining material pocket technology to provide physical support to a powdered sample within an immersion bath. IMP-DMA allows the mechanical response of a powder during heating to be monitored in excess water. IMP-DMA was evaluated using a range of starch samples loaded as a slurry into a solid steel pocket, the mechanical responses of these samples were monitored as a function of temperature, and values for modulus and tan delta peaks were found to correspond well with events occurring at both the onset and peak gelatinisation temperatures as measured by differential scanning calorimetry (DSC) (e.g. wheat starch has an onset and peak DSC temperature of 49.3 degrees C and 57.2 degrees C, respectively, and shows a peak in tan delta at 52.8 degrees C and a modulus peak at 57.7 degrees C). Some limitations were found in the ability of DMA to detect transitions in starches with low or high amylose contents. IMP-DMA was shown to be an effective tool for monitoring the changes in starch structure that occur during gelatinisation, both in purified starches and in more complex starch-containing food materials. Thus, a new hyphenated form of DMA is now available that permits the thermally induced transitions of particle water dispersions to be characterised. (C) 2012 Elsevier Ltd. All rights reserved.
AB - There is a clear need for improved methods for the study of the physical changes that occur in slurries and sol-gel systems that have significant water content. In this paper a novel immersion mode material pocket form of dynamic mechanical analysis (IMP-DMA) has been designed, combining material pocket technology to provide physical support to a powdered sample within an immersion bath. IMP-DMA allows the mechanical response of a powder during heating to be monitored in excess water. IMP-DMA was evaluated using a range of starch samples loaded as a slurry into a solid steel pocket, the mechanical responses of these samples were monitored as a function of temperature, and values for modulus and tan delta peaks were found to correspond well with events occurring at both the onset and peak gelatinisation temperatures as measured by differential scanning calorimetry (DSC) (e.g. wheat starch has an onset and peak DSC temperature of 49.3 degrees C and 57.2 degrees C, respectively, and shows a peak in tan delta at 52.8 degrees C and a modulus peak at 57.7 degrees C). Some limitations were found in the ability of DMA to detect transitions in starches with low or high amylose contents. IMP-DMA was shown to be an effective tool for monitoring the changes in starch structure that occur during gelatinisation, both in purified starches and in more complex starch-containing food materials. Thus, a new hyphenated form of DMA is now available that permits the thermally induced transitions of particle water dispersions to be characterised. (C) 2012 Elsevier Ltd. All rights reserved.
U2 - 10.1016/j.carbpol.2012.05.088
DO - 10.1016/j.carbpol.2012.05.088
M3 - Article
SN - 0144-8617
VL - 90
SP - 628
EP - 636
JO - CARBOHYDRATE POLYMERS
JF - CARBOHYDRATE POLYMERS
IS - 1
ER -