|ALAMRI, M - King Saud University|
|AL-RUQUIE, I - King Abdullah University Of Science And Technology|
|HUSSAIN, S - King Saud University|
|MOHAMED, A - King Saud University|
|Xu, Jingyuan - James|
Submitted to: Quality Assurance and Safety of Crops & Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/12/2014
Publication Date: 1/1/2015
Citation: Alamri, M.S., Al-Ruquie, I.M., Hussain, S., Mohamed, A.A., Xu, J. 2015. Gelatinisation kinetics of corn and chickpea starches using DSC, RVA, and dynamic rheometry. Quality Assurance and Safety of Crops & Foods. 7(4):459-468.
Interpretive Summary: Starch is a polymeric carbohydrate consisting of glucose units. When starch is heated in excess of water, it loses its ordered state. This process is known as gelatinization. It is responsible for the thickening of food systems. This work used three different methods to study the kinetics of the corn and chickpea starch gelatinization in order to find advantages and disadvantages for different methods. In addition, the chickpea starch gelatinization kinetics was not studied and reported before. We discovered that the activation energy estimated by DSC (Differential Scanning Calorimetry) and RVA (Rapid Visco Analyzer) methods was comparable; and gelatinization kinetic orders could be well estimated by rheometry. The results of this work can be used to effectively direct and control different food process procedures with starch. Another outcome of this study is providing a better understanding of chickpea starch gelatinization kinetics for the first time, which could lead to expansion of chickpea starch usages.
Technical Abstract: The gelatinisation kinetics (non-isothermal) of corn and chickpea starches at different heating rates were calculated using differential scanning calorimetry (DSC), rapid visco analyser (RVA), and oscillatory dynamic rheometry. The data obtained from the DSC thermogram and the RVA profiles were fitted to Kissinger's and Ozawa's methods. Starch gelatinisation was characterised by two phases, where the first correspondeded to the unfolding of amorphous region of the starch granule and the other represented the melting crystalline part. The temperature that separates the unfolding and melting of the granule parts, the breaking temperature, was recorded. Higher activation energy (Ea) was calculated for the DSC data versus the RVA. The Ea values calculated by Kissinger's method indicated that one can use either DSC or RVA to get a comparable Ea for both starches, whereas Ozawa's method showed comparable results for chickpea starch and less comparable for corn starch. The Ea of corn starch as calculated by dynamic rheometry (549 kJ/mol) was comparable.