II.3.5.15 Treatment with silver chloride

Definition:

Addition of silver chloride to wine

Objective:

To reduce odour defects due to hydrogen sulphide and some mercaptans.

Prescriptions

a)        The dose used must not be over 1 g/hl

b)       The silver chloride must be previously applied to an inert support, like kieselguhr (diatomaceous earth) or kaolin

c)        The main operation must be preceded by trials to determine the amount of product to add.

d)       The precipitate must be eliminated by any appropriate physical procedure

e)       Residues must be treated by specialised sector

f)         Treated wine must be analysed to insure that the maximal residue level do not exceed 0.1 mg/L in silver

g)        The treatment must  be carried out under the responsibility of an oenologist or a specialised technician

h)       Silver chloride must comply with the provisions of the International Oenological Codex

Recommendation of the OIV:

Admitted