| Abstract
| - The antioxidant activities of anthocyanins and anthocyanin fractions isolated from blackcurrants,raspberries, and lingonberries were investigated in whey protein-stabilized emulsion. The extent ofprotein oxidation was measured by determining the loss of tryptophan fluorescence and formation ofprotein carbonyl compounds and that of lipid oxidation by conjugated diene hydroperoxides andhexanal analyses. The antioxidant activity of berry anthocyanins increased with an increase inconcentration. Blackcurrant anthocyanins were the most potent antioxidants toward both protein andlipid oxidation at all concentrations due to the beneficial combination of delphinidin and cyanidinglycosides. Most berry anthocyanins (69.4−72.8%) partitioned into the aqueous phase of the emulsion,thus being located favorably for antioxidant action toward protein oxidation. The presence of the lipiddecreased the share of anthocyanin in the aqueous phase. Thus, the structure of food affects theantioxidant activity by influencing the partitioning of the antioxidant. Keywords: Protein oxidation; anthocyanins; antioxidants; partition; emulsion; berries
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