Ultrasonic monitoring of the gelatinisation of starch
Laurent Lehmann, Evgeny Kudryashov, Vitaly Buckin
Progr Colloid Polym Sci, Vol. 123, pp. 136–140 (2004)
High-resolution ultrasonic spectroscopy was applied to analysis of starch gelatinisation. Temperature profiles of ultrasonic attenuation and velocity were obtained in three different starch suspension samples (corn, rice and wheat) at 25% w/w starch-water ratio using the ascending temperature ramp regime (2ºC/min) in the range of 37ºC to 95ºC. Both ultrasonic velocity and attenuation decrease upon the gelatinisation process. Three regions in the temperature profile of the ultrasonic velocity and attenuation were distinguished during formation of starch gel and attributed to the successive steps involved in the gelatinisation process. The effects of concentration and chemical composition of starch on ultrasonic parameters were observed and interpreted in terms of microrheological parameters of the starch suspensions and gels. Temperature profiles of both ultrasonic velocity and attenuation were also found to be frequency dependent and this was related to the microstructure of starch.