title: Development and validation of a near infrared spectrophotometric method to determine total antioxidant activity of milk.
abstract: In the present study a spectrophotometric method for the determination of total antioxidant activity (TAA) based on ABTS assay was developed and validated on raw milk (RM), whole UHT milk (WUM), partially skimmed UHT milk (SUM), whole pasteurised milk (WM) and partially skimmed pasteurised milk (SM). The most suitable solvent for antioxidant extraction was 80% acetone. Regardless of the type of milk, the coefficient of determination from the linearity test was greater than 0.95. The limit of detection ranged from 0.74 to 6.07μmoll-1Trolox equivalents. Repeatability, calculated as relative standard deviation of twenty measurements within a day, and reproducibility, calculated as relative standard deviation of sixty measurements across three days, ranged from 1.24 to 4.04% and from 2.18 to 3.52%, respectively. Preservative added to RM had negligible effects on the TAA of milk. The greatest TAA was measured for SM followed by SUM, RM, WM and WUM.
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy. Electronic address: giovanni.niero@phd.unipd.it.
authors.forename: G
authors.initials: G
authors.lastname: Niero
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Penasa
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Currò
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Masi
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: A R
authors.initials: AR
authors.lastname: Trentin
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Cassandro
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
authors.forename: M
authors.initials: M
authors.lastname: De Marchi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D008892:Milk / Q000378:metabolism*; D015203:Reproducibility of Results; D013053:Spectrophotometry / Q000379:methods*
chemical_list: D000975:Antioxidants
keywords: Free radical; Milk; Nutraceutical; Repeatability; Reproducibility; Spectrophotometer