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A series of dicarboxylic-amylose inclusion complexes (AIC) were prepared by excess steam jet-cooking high amylose corn starch with linear C10, C12, C14, and C16 dicarboxylic acids to examine the influence of two polar head groups on complex formation. The C12, C14, and C16 dicarboxylic acid AIC were prepared in 48-63 % yields and contained 8.9-11.8 % diacid while the C10 AIC gave 30 % and contained 2.6 % diacid. These AIC had V6 helical amylose structures by XRD and complexation was further confirmed by DSC, FTIR, and TGA. SEM of the C12-C16 AIC revealed micron-sized toroidal spherulites while the C10 AIC was predominantly amorphous. DSC showed two AIC related transitions. This work provides a better understanding of the formation and physicochemical properties of these diacid AIC. Preparation by excess steam jet cooking demonstrates practical and commercial utility to prepare AIC as off-the-shelf materials for food and nonfood applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

The use of starch in polymer composites for film production has been studied for increasing biodegradability, improving film properties and reducing cost. In this study, submicron particles were prepared from amylose-sodium palmitate complexes both by rapidly cooling jet-cooked starch-palmitic acid mixtures and by acidifying solutions of starch-sodium palmitate complexes. Films were cast containing poly(vinyl alcohol) (PVOH) with up to 50% starch particles. Tensile strength decreased and Young's modulus increased with starch concentration, but percent elongations remained similar to controls regardless of preparation method or starch content. Microscopy showed particulate starch distribution in films made with rapidly cooled starch-palmitic acid particles but smooth, diffuse starch staining with acidified sodium palmitate complexes. The mild effects on tensile properties suggest that submicron starch particles prepared from amylose-palmitic acid complexes provide a useful, commercially viable approach for PVOH film modification., (Published by Elsevier Ltd.)

Amylose inclusion complexes were prepared from jet-cooked aqueous mixtures of high amylose corn starch and 1-hexadecylamine (HDA). Slow-cooling produced torus/disc-shaped spherulites, whereas aggregates of smaller spherulites were obtained by rapid-cooling in ice. The morphologies and 61V X-ray diffraction patterns of these spherulites were similar to those of spherulites obtained previously with palmitic acid, indicating that spherulite morphology is influenced largely by the hydrophobic structure of the carbon chain of the complex-forming ligand and to a lesser extent by the nature of the more polar head group. Water soluble, cationic amylose inclusion complexes were prepared by adding an aqueous solution of the HCl salt of HDA to a jet-cooked dispersion of high amylose starch. The cationic nature of these HDA·HCl complexes suggests possible applications as flocculating agents for water purification and as retention aids in papermaking., (Published by Elsevier Ltd.)