Treatment of must with glutathione

Status: In force

Treatment of must with glutathione

RESOLUTION OIV-OENO 445-2015

TREATMENT OF MUST WITH GLUTATHIONE

THE GENERAL ASSEMBLY,

In view of Article 2, paragraph 2 ii of the Agreement of 3 April 2001 establishing the International Organisation of Vine and Wine,

Considering the work of the “Technology” Expert Group, which showed that the addition of glutathione makes it possible to trap quinones, significantly limiting changes in the colour of the must towards yellow-brown shades, confirming the ability of glutathione to limit oxidation phenomena

Considering that the presence of glutathione in musts makes it possible to maintain the varietal aromatic potential (particularly of the thiol family) during the processing of grapes into wine,

Considering the favourable opinion given by the “Food Safety” Group,

DECIDES, following a proposal made by Commission II “Oenology”, to introduce the following oenological practices and treatments into part II, Chapter 2 of the International Code of Oenological Practices:

PART II

Chapter 2: Musts

GLUTATHIONE TREATMENT

Definition:

Addition of glutathione to musts.

Objective:

To limit the intensity of oxidation phenomena in musts, thanks to the ability of glutathione to trap quinones and reduce their oxidative activity.

Prescriptions:

  1. It is advised to add the glutathione while obtaining the musts or at the start of alcoholic fermentation, ensuring that, prior to and during alcoholic fermentation, the assimilable nitrogen level is sufficient to avoid the metabolism of glutathione by the yeast;
  2. the dose used should not exceed 20 mg/L;
  3. the glutathione must be in a reduced form and comply with the prescriptions of the International Oenological Codex.

OIV recommendation:

Accepted.