Detection and quantification of lysozyme in champagne wines

We describe here techniques to detect and quantify lysozyme in Pinot noir a nd Chardonnay Champagne wines. Using a dot-blot technique, lysozyme antibod ies were able to recognize their antigens even when the concentration of ly sozyme in wine was 75 mg/L. SDS-PAGE was the second technique used. After C oomassie Brilliant Blue (CBB) staining-or antibody immunostaining was perfo rmed, the wine originating from the lysozyme-treated must gave only one ban d corresponding to the lysozyme, It is then possible to precisely determine the concentration of lysozyme in a must or a wine by densitometric measure ment of this band. The control wine gave no band with the CBB staining, suc h as with the immunostaining. The quantification, of lysozyme with HPLC is another useable technique because the lysozyme elution time is largely supe rior to that of all of the wine compounds. In wines, losses of lysozyme wer e higher when the enzyme was added at one time to the must (-34% for the Pi not noir and -37% for the Chardonnay) than when lysozyme is added in a-fold both in the must and in the wine (around -26% for the two wines). The lowe st diminution is observed when lysozyme was added to the wine only (-18%) i n comparison to the addition to the must at 300 mg/L (-43%).