International Code of Oenological Practices

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II.3.2.2 Filtration


  • Diatomite: processing aid
  • Perlite: processing aid


Physical process consisting of passing the wine through appropriate filters that retain particles in suspension.


a)        Clarifying the wine, if necessary by successive stages (clarifying filtration).

b)       Obtaining biological stability of the wine by elimination of microorganisms (sterilising filtration).


Filtration can be undertaken:

a)        By continuous deposition, using appropriate additives such as diatomaceous earth, perlite, cellulose…,

b)       On pads of cellulose or other appropriate materials,

c)        On mineral or organic membranes of a porosity greater than or equal to 0.2 m (microfiltration).

The filter materials used shall comply with the prescriptions of the International Oenological Codex.

Recommendation of OIV:

Refer to the practices and treatments mentioned hereafter.