Adsorbant copolymer treatment pvi/pvp (musts chapter)
RESOLUTION OENO 1/2007
ADSORBANT COPOLYMER TREATMENT PVI/PVP (MUSTS CHAPTER)
THE GENERAL ASSEMBLY,
CONSIDERING the works of the experts group “International Code of Oenological Practices”,
DECIDES:
Upon the proposal by Commission II “Oenology”, to introduce in the “International Code of Oenological Practices” the following oenological practice:
PART II
Chapter 2 (Musts)
Adsorbant Copolymer treatment PVI/PVP
Definition:
The addition of polyvinylimidazole – polyvinylpyrrolidone copolymers (PVI/PVP) in order to reduce copper, iron and heavy metal contents.
Objectives:
- To prevent defects caused by too high metal contents (for example ferric casse).
- To reduce undesirable high concentration of metals due to:
- Must contaminated by metal cations (for example by residues from phytosanitary products containing copper),
- Metal cation contamination during must treatment from winemaking equipment.
Prescriptions:
- The amount used should be less than 500 mg/l.
- When musts and wine are treated with PVI/PVP copolymers, the accumulated dosage should be less than 500 mg/l.
- The copolymers should be eliminated by filtration no later than two days after the addition taking into account the precautionary principle. In the case of cloudy musts, the copolymer must be added no earlier than a maximum of two days before filtration.
- The adsorbant copolymers used should comply with the prescriptions of the International Oenological Codex and in particular monomers limits.
- The implementation of the procedure shall be placed under the responsibility of an oenologist or a specialised technician pending the adoption of the monograph.
Recommendation of the OIV:
Admitted *[1]
[1] *Note : this practice shall enter into force only following the adoption of the PVI/PVP polymer monograph integrating particularly purity and stability criteria in addition to method of analytical determination of monomers