Effect of ultrasonically induced nucleation on ice crystals' size and shape during freezing in vials

Abstract This work aimed at determining empirical correlations between the final frozen product ice crystals’ characteristics (mean size and shape) and ultrasound assisted freezing operating conditions (supercooling and acoustic power). For this purpose 10% w/w mannitol aqueous solution samples contained in vials were frozen by means of a refrigerated shelf coupled with an ultrasonic device able to induce ice nucleation. Ice crystals’ were observed using reflected light optical microscopy over samples’ transversal and longitudinal sections in a cold chamber. A response surface analysis based on a five levels composite experimental design had been carried out. It was found that increasing supercooling and acoustic power resulted in decreasing ice crystals’ mean size and increasing their mean circularity.

[1]  B. Chalmers Principles of Solidification , 1964 .

[2]  D. Kashchiev,et al.  Review: Nucleation in solutions revisited , 2003 .

[3]  Birgit Glasmacher,et al.  Reduction of primary freeze-drying time by electric field induced ice nucleus formation , 2006 .

[4]  R. Peczalski,et al.  A theoretical model for ice primary nucleation induced by acoustic cavitation. , 2010, Ultrasonics sonochemistry.

[5]  Akira Yabe,et al.  Active control of phase change from supercooled water to ice by ultrasonic vibration 1. Control of freezing temperature , 2001 .

[6]  Sangyoub Lee,et al.  Freezing transition of interfacial water at room temperature under electric fields. , 2005, Physical review letters.

[7]  P. W. Cains,et al.  Sonocrystallization: The Use of Ultrasound for Improved Industrial Crystallization , 2005 .

[8]  R. Hickling,et al.  Nucleation of Freezing by Cavity Collapse and its Relation to Cavitation Damage , 1965, Nature.

[9]  Julien Andrieu,et al.  Influence of controlled nucleation by ultrasounds on ice morphology of frozen formulations for pharmaceutical proteins freeze-drying , 2006 .

[10]  J. Carpenter,et al.  The ice nucleation temperature determines the primary drying rate of lyophilization for samples frozen on a temperature-controlled shelf. , 2001, Journal of pharmaceutical sciences.

[11]  R. Chivers,et al.  A study on the primary and secondary nucleation of ice by power ultrasound. , 2005, Ultrasonics.

[12]  H. Kramer,et al.  Primary nucleation induced by ultrasonic cavitation , 2006 .

[13]  M. A. Margulis,et al.  Sonochemistry and cavitation , 1995 .

[14]  Julien Andrieu,et al.  Effect of ultrasound-controlled nucleation on structural and morphological properties of freeze-dried mannitol solutions , 2008 .

[15]  R. Chivers,et al.  The microscopic visualisation of the sonocrystallisation of ice using a novel ultrasonic cold stage. , 2004, Ultrasonics sonochemistry.

[16]  Michael J. Pikal,et al.  Heat and mass transfer scale-up issues during freeze drying: II. Control and characterization of the degree of supercooling , 2004, AAPS PharmSciTech.

[17]  L. Otero,et al.  High‐Pressure Shift Freezing. Part 1. Amount of Ice Instantaneously Formed in the Process , 2000, Biotechnology progress.

[18]  Malcolm Povey,et al.  The sonocrystallisation of ice in sucrose solutions: primary and secondary nucleation. , 2003, Ultrasonics.