title: Amylose crystallization from concentrated aqueous solution.
abstract: Maize amylose, separated from granular starch by means of an aqueous leaching process, was used to investigate spherulite formation from concentrated mixtures of starch in water. Amylose (10-20%, w/w) was found to form a spherulitic semicrystalline morphology over a wide range of cooling rates (1-250 degrees C/min), provided it was first heated to >170 degrees C. This is explained through the effect of temperature on chain conformation. A maximum quench temperature of approximately 70 degrees C was required to produce spherulitic morphology. Quench temperatures between 70 and 110 degrees C produced a gel-like morphology. This is explained on the basis of the relative kinetics of liquid-liquid phase separation vis-à-vis crystallization. The possibility of the presence of a liquid crystalline phase affecting the process of spherulite formation is discussed.
authors.affiliation: The Pennsylvania State University, 116 Borland Lab, University Park, 16801, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Creek
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Ziegler
authors.forename: James
authors.initials: J
authors.lastname: Runt
mesh_terms: D000688:Amylose / Q000737:chemistry*; D003460:Crystallization; D007700:Kinetics; D046911:Macromolecular Substances; D009682:Magnetic Resonance Spectroscopy; D011108:Polymers / Q000737:chemistry; D013213:Starch / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction; D003313:Zea mays / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D011108:Polymers; D014867:Water; D013213:Starch; D000688:Amylose