Abstract
The crystallization behaviour of fats without and with application of ultrasonic power is investigated in-situ using a synchrotron radiation time resolved small angle X-ray scattering (SAXS) and wide angle X-ray scattering (WAXS). Without ultrasound application, both polymorhic forms β' and β crystallized in the melt of each substance. With ultrasound treatment of the melt the following effects were observed: (i) a marked decrease of induction times for crystallization with respect to those obtained without application of ultrasound, (ii) an increased nucleation rate compared to that without ultrasound treatment, and (iii) a crystallization of only β forms under conditions of initial crystallization temperature of 50℃ and 30℃, respectively, and applied ultrasound of 2 sec. The last finding demonstrates that ultrasound irradiation can be used as an efficient tool for controlling polymorphic crystallization of fats.
