title: Acacia gum as modifier of thermal stability, solubility and emulsifying properties of α-lactalbumin.
abstract: Protein-polysaccharide conjugates often display improved techno-functional properties when compared to their individual involved biomolecules. α-Lactalbumin:acacia gum (α-la:AG) conjugates were prepared via Maillard reaction by the dry-heating method. Conjugate formation was confirmed using results of absorbance, o-phthalaldehyde test, sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography. Techno-functional properties (emulsifying characteristics, solubility, and thermal stability) were evaluated for α-la, α-la/AG mixtures and α-la:AG conjugates. Conjugate thermal stability was improved compared to pure α-la treated at the same conditions of conjugate formation. Response surface methodology was used to establish models to predict solubility and emulsifying activity as functions of the salt concentration, pH and reaction time. α-la:AG conjugate solubility is affected in a complex manner by the three factors analyzed. Emulsifying activity index (EAI) of α-la is significantly affected by pH, while the α-la:AG EAI is affected by the three analyzed factors. Both solubility and EAI are maximized with pH 8.0, NaCl concentration of 0.3 mol L(-1) and two days of Maillard reaction.
authors.affiliation: Departamento de Ciência e Tecnologia de Alimentos, Instituto Federal de Educação, Ciência e Tecnologia do Sudeste de Minas Gerais-Campus Rio Pomba, Av. Dr. José Sebastião da Paixão, s/n, 36180-000 Rio Pomba, MG, Brazil; Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil.
authors.forename: Fabíola Cristina
authors.initials: FC
authors.lastname: de Oliveira
authors.affiliation: Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil. Electronic address: jcoimbra@ufv.br.
authors.forename: Jane Sélia
authors.initials: JS
authors.lastname: Dos Reis Coimbra
authors.affiliation: Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil.
authors.forename: Eduardo Basílio
authors.initials: EB
authors.lastname: de Oliveira
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Minas Gerais (UFMG), Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: Marina Quadrio Raposo Branco
authors.initials: MQ
authors.lastname: Rodrigues
authors.affiliation: Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil.
authors.forename: Rachel Campos
authors.initials: RC
authors.lastname: Sabioni
authors.affiliation: Departamento de Engenharia de Pesca, Universidade Federal do Ceará, Fortaleza, CE, Brazil.
authors.forename: Bartolomeu Warlene Silva
authors.initials: BW
authors.lastname: de Souza
authors.affiliation: Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa (UFV), Av. P. H. Rolfs, s/n, 36570-000 Viçosa, MG, Brazil.
authors.forename: Igor José Boggione
authors.initials: IJ
authors.lastname: Santos
mesh_terms: D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004655:Emulsions / Q000737:chemistry*; D006170:Gum Arabic / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007768:Lactalbumin / Q000737:chemistry*; D015416:Maillard Reaction; D055550:Protein Stability; D012492:Salts / Q000737:chemistry; D012995:Solubility; D013696:Temperature; D013997:Time Factors
chemical_list: D004655:Emulsions; D012492:Salts; D006170:Gum Arabic; D007768:Lactalbumin
keywords: Emulsifying properties; Glycosylation; Solubility; Thermal stability; Whey protein