title: Interactions of buttermilk with curcuminoids.
abstract: The ability of buttermilk to carry and stabilise a preparation of curcuminoids was examined. The quenching of intrinsic protein fluorescence confirmed that the curcuminoids interacted with proteins in buttermilk. The Stern-Volmer quenching constant was ≥ 9.4 × 10³ M⁻¹. The apparent binding constant of curcuminoids to whole buttermilk was ≥ 2.2 × 10⁴ M⁻¹. Centrifugation of buttermilk (5% total solids, TS)--curcuminoid mixtures demonstrated that curcuminoids were partitioned into the cream (18.0%w/w, 0.64% TS), milk serum (73.3%w/w, 2.86% TS) and the casein-rich precipitate (6.76% w/w, 1.87% TS) fractions in the ratio of 1:3.7:3.5. The interaction of curcuminoids with components in the buttermilk improved its stability, as evidenced by the faster degradation of curcuminoids in phosphate buffer (pH=6.8) than in buttermilk. The ability of buttermilk to carry and stabilise curcuminoids has the potential to enable the delivery of these components into functional foods.
authors.affiliation: Department of Agriculture & Food Systems, Melbourne School of Land & Environment, University of Melbourne, Victoria 3010, Australia; CSIRO Preventative Health National Research Flagship, CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, Victoria 3030, Australia.
authors.forename: Shishan
authors.initials: S
authors.lastname: Fu
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Shen
authors.forename: Said
authors.initials: S
authors.lastname: Ajlouni
authors.forename: Ken
authors.initials: K
authors.lastname: Ng
authors.forename: Luz
authors.initials: L
authors.lastname: Sanguansri
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Augustin
mesh_terms: D000818:Animals; D002417:Cattle; D043302:Cultured Milk Products / Q000737:chemistry*; D030024:Curcuma / Q000737:chemistry*; D003474:Curcumin / Q000031:analogs & derivatives* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008894:Milk Proteins / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*
chemical_list: D008894:Milk Proteins; D010936:Plant Extracts; D003474:Curcumin
keywords: Binding; Buttermilk; Carrier; Curcuminoids; Functional food; Stability