Material and packaging for yeast storage

Method for the storage of a liquid or semi-liquid yeast or leaven, said method comprising a step of:

• storing the liquid or semi-liquid yeast or leaven in a packaging,
• wherein:
• the packaging comprises a container composed of two plastic films, wherein the first plastic film is a three-layer plastic film with a B-A-B′ structure and the second plastic film is uniformly perforated;
• the first plastic film defines the internal volume of the container;
• and
• the container is in the form of a pouch having a total internal volume of between 1 liter and 1000 liters;
• and wherein:
• layer A of the three-layer plastic film consists of an ethylene-vinyl acetate (EVA) with a high vinyl acetate content, as percentage by weight, of between 18% and 42%, and
• each of layers B and B′ of the three-layer plastic film consists of an ethylene-vinyl acetate (EVA) having a vinyl acetate content, as percentage by weight, which is lower than that of the ethylene-vinyl acetate of layer A,
• the permeability of the three-layer plastic film to carbon dioxide, measured according to ISO standard 15105-2:2003 annex B, is greater than or equal to 80 l/m2·24 h at delta P=1 bar,
• the three-layer plastic film has a total thickness of from 20 to 50 microns, and
• the permeability of the three-layer plastic film to oxygen (O2), measured according to ISO standard 1510-2:2003 annex B, is less than or equal to 30 l/m2·24 h at delta P=1 bar.