Determination of Residual Egg White Proteins in Red Wines during and after Fining

Abstract

Methods are needed for detecting allergenic proteins in wine after fining processes, both for legal requirements and to estimate any risk for allergic individuals. One of the critical allergens in this case is the protein fraction from egg white. The efficacy of use of a commercial egg protein detection kit was evaluated using wines spiked with egg protein. For calibration, a whole egg powder reference material was used. There were no matrix effects and the detection limit was 0.27 mg whole egg powder/L. The intra- and interassay coefficients of variation were 7.3% and 11.9%, respectively. Recoveries of different egg preparations in spiked red wine were between 80 and 110%. A field study showed different concentrations of egg during fining, but no detectable or low values of ≤1 mg/L in the bottled wine.