title: Effects of high hydrostatic pressure and chemical reduction on the emulsification properties of gum arabic.
abstract: Gum arabic is widely used in the food industry as an additive, both as a thickener and an emulsifier. This study has compared the emulsification properties of two types of gums, KLTA (Acacia senegal) and GCA (Acacia seyal), both in their native/untreated forms and after exposure to high pressure (800 MPa). Further studies were undertaken to chemically modify the disulphide linkages present and to investigate the effects of their reduction on the diffusion of the carbohydrate materials. The emulsification properties of the gum samples were examined by determining the droplet size distribution in a "model" oil-in-water system. Results showed that high pressure treatment and chemical reduction of gums changed the emulsification properties of both gums. The high molecular weight component in arabinogalactan-proteins (AGP/GP), and more "branched" carbohydrates present in gum arabic, may be responsible for the emulsification properties of GCA gum, indicating that the emulsification mechanisms for KLTA and GCA were different.
authors.affiliation: Department of Food and Nutrition Science, University of Reading, Whiteknights, Reading RG6 6AP, UK.
authors.forename: Fanyi
authors.initials: F
authors.lastname: Ma
authors.affiliation: Department of Food and Nutrition Science, University of Reading, Whiteknights, Reading RG6 6AP, UK.
authors.forename: Alan E
authors.initials: AE
authors.lastname: Bell
authors.affiliation: Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AP, UK.
authors.forename: Fred J
authors.initials: FJ
authors.lastname: Davis
authors.affiliation: Department of Food and Nutrition Science, University of Reading, Whiteknights, Reading RG6 6AP, UK.
authors.forename: Yunxi
authors.initials: Y
authors.lastname: Chai
mesh_terms: D000045:Acacia / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D045703:Emulsifying Agents / Q000737:chemistry*; D006170:Gum Arabic / Q000737:chemistry*; D006874:Hydrostatic Pressure; D008970:Molecular Weight; D009088:Mucoproteins / Q000737:chemistry; D010940:Plant Proteins / Q000737:chemistry
chemical_list: D004220:Disulfides; D045703:Emulsifying Agents; D009088:Mucoproteins; D010940:Plant Proteins; C006619:arabinogalactan proteins; D006170:Gum Arabic
keywords: Arabinogalactan protein (AGP); Emulsification properties; Gum arabic; High pressure treatment; Reduction of carbohydrate side chain