title: Aggregate and emulsion properties of enzymatically-modified octenylsuccinylated waxy starches.
abstract: Sorghum and maize waxy starches were hydrophobically modified with octenylsuccinic anhydride (OSA) and treated with enzymes before being used to emulsify β-carotene (beta,beta-carotene) and oil in water. Enzyme treatment with β-amylase resulted in emulsions that were broken (separated) earlier and suffered increased degradation of β-carotene, whereas treatment with pullulanase had little effect on emulsions. Combinations of surfactants with high and low hydrodynamic volume (V(h)) indicated that there is a relationship between V(h) and emulsion stability. Degree of branching (DB) had little direct influence on emulsions, though surfactants with the highest DB were poor emulsifiers due to their reduced molecular size. Results indicate that V(h) and branch length (including linear components) are the primary influences on octenylsuccinylated starches forming stable emulsions, due to the increased steric hindrance from short amphiphilic branches, consistent with current understanding of electrosteric stabilization. The success of OSA-modified sorghum starch points to possible new products of interest in arid climates.
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China; The University of Queensland, Centre for Nutrition and Food Sciences, Queensland Alliance for Agricultural and Food Innovation, Brisbane, QLD 4072, Australia.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Sweedman
authors.affiliation: DSM Nutritional Products Ltd., R&D Center Formulation & Application, P.O. Box 2676, 4002 Basel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Schäfer
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China; The University of Queensland, Centre for Nutrition and Food Sciences, Queensland Alliance for Agricultural and Food Innovation, Brisbane, QLD 4072, Australia. Electronic address: b.gilbert@uq.edu.au.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Gilbert
mesh_terms: D045703:Emulsifying Agents / Q000737:chemistry* / Q000378:metabolism; D004655:Emulsions / Q000737:chemistry / Q000378:metabolism; D045868:Sorghum / Q000737:chemistry*; D013213:Starch / Q000737:chemistry* / Q000378:metabolism; D013305:Streptomyces griseus / Q000201:enzymology; D013386:Succinates / Q000737:chemistry* / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry*; D019207:beta Carotene / Q000737:chemistry; D001614:beta-Amylase / Q000378:metabolism
chemical_list: D045703:Emulsifying Agents; D004655:Emulsions; D013386:Succinates; D019207:beta Carotene; D013213:Starch; D001614:beta-Amylase
keywords: Chemical degradation; Critical aggregation concentration; Emulsion stability; Octenylsuccinic anhydride starch; Structural modification