title: Hypochlorous and peracetic acid induced oxidation of dairy proteins.
abstract: Hypochlorous and peracetic acids, both known disinfectants in the food industry, were compared for their oxidative capacity toward dairy proteins. Whey proteins and caseins were oxidized under well controlled conditions at pH 8 as a function of the sanitizing concentration. Different markers for protein oxidation were monitored. The results established that the protein carbonyl content was a rather unspecific marker for protein oxidation, which did not allow one to differentiate the oxidant used especially at the lower concentrations. Cysteine, tryptophan, and methionine were proven to be the most vulnerable amino acids for degradation upon hypochlorous and peracetic acid treatment, while tyrosine was only prone to degradation in the presence of hypochlorous acid. Hypochlorous acid induced oxidation gave rise to protein aggregation, while during peracetic acid induced oxidation, no high molecular weight aggregates were observed. Protein aggregation upon hypochlorous acid oxidation could primarily be linked to tryptophan and tyrosine degradation.
authors.affiliation: NutriFOODchem unit, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kerkaert
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mestdagh
authors.forename: Tatiana
authors.initials: T
authors.lastname: Cucu
authors.forename: Philip Roger
authors.initials: PR
authors.lastname: Aedo
authors.forename: Shen Yan
authors.initials: SY
authors.lastname: Ling
authors.forename: Bruno
authors.initials: B
authors.lastname: De Meulenaer
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D002364:Caseins / Q000737:chemistry*; D004202:Disinfectants / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006997:Hypochlorous Acid / Q000737:chemistry*; D008894:Milk Proteins / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D010463:Peracetic Acid / Q000737:chemistry*; D000067816:Whey Proteins
chemical_list: D000596:Amino Acids; D002364:Caseins; D004202:Disinfectants; D008894:Milk Proteins; D016877:Oxidants; D000067816:Whey Proteins; D006997:Hypochlorous Acid; D010463:Peracetic Acid