title: Comparative Emulsifying Properties of Octenyl Succinic Anhydride (OSA)-Modified Starch: Granular Form vs Dissolved State.
abstract: The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable.
authors.affiliation: Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden.|Department of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain.
authors.forename: María
authors.identifier: http://orcid.org/0000-0002-6980-0554
authors.initials: M
authors.lastname: Matos
authors.affiliation: Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden.
authors.forename: Ali
authors.initials: A
authors.lastname: Marefati
authors.affiliation: Department of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Gutiérrez
authors.affiliation: Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Wahlgren
authors.affiliation: Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Rayner
mesh_terms: D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D007700:Kinetics; D008853:Microscopy; D009821:Oils / Q000737:chemistry; D010316:Particle Size; D013213:Starch / Q000031:analogs & derivatives* / Q000737:chemistry; D013387:Succinic Anhydrides / Q000737:chemistry*
chemical_list: D045703:Emulsifying Agents; D004655:Emulsions; D009821:Oils; D013387:Succinic Anhydrides; C551966:octenyl succinic anhydride-modified starch; D013213:Starch