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Thefunctions of three starches (potato, corn, and rice) on the formation of starch andpork ham batter composite during heating were investigated. Thermal properties were measured by differential scanning calorimetry (DSC) and rheological characteristics were determined by small amplitude oscillatory shearing. DSC thermograms did not show any chemical interactions between starch and meat protein during heating. The dramatic increase in G' and G" of starch/meat composite appeared to be associated with the gelatinization of starch. The microstructures of pork ham batter, starch, and starch/meat composites were revealed by both scanning electron microscopy and light microscopy.

Kinetics of the phase transition of native and chemically modified rice starches have been investigated by using differential scanning calorimetry (DSC) after isothermal treatment. At the experimental conditions, the phase transition of these starches followed pseudo-first order kinetics. The kinetic order was not affected by the two chemical modifications used, hydroxypropylation and cross-linking, while the rate constants were altered. From the Arrhenius plot, peak temperature (T,) from DSC thermogram appeared to be the turning point for the two steps, swelling and disruption/dissolution, associated in the phase transition of starch granules. When the temperature was below T,, high activation energy was obtained and fell in the range of 61 to 75kcal/mol. Once the temperature was above T,, the activation energy dropped to be in the range of 10 to 30kcal/mol and the starch became less temperature sensitive. Kinetik des Phasenuberganges von nativen, vernetzten und hydroxypropylierten Reissurken. Die Kinetik des Phaseniiberganges von nativen und chemisch modifizierten Reisstarken wurde untersucht unter Anwendung der Differential-Raster-Calorimetrie (DSC) nach isothermischer Behandlung. Unter den experimentellen Bedingungen folgte der Phaseniibergang dieser Starken einer Pseudo-1. Ordnung-Kinetik. Die Kinetik-Ordnung wurde nicht durch die beiden chemischen Modifizierungen, Hydroxypropylierung und Vernetzung, beeinflunt, wahrend sich die Geschwindigkeitskonstanten veranderten. Aus der Arrhenius-Darstellung schien die Spitzentemperatur (T,) des DSC-Thermogrammes der Wendepunkt fur die beiden Stufen, Quellung und ZerreiBung/Auflosung, mit dem Phaseniibergang der Starkekorner assoziiert. Wenn die Temperatur unterhalb T, wurde eine hohe Aktivierungsenergie erreicht und fiel in den Bereich von 61 bis 75kcal/mol. Wenn die Temperatur iiber T, war, so fiel die Aktivierungsenergie in den Bereich von 10 bis 30kcal/mol, und die Starke wurde weniger temperaturempfindlich.