摘要 |
<p>The invention relates to the use of a three-layer plastic film that is permeable to carbon dioxide but slightly impermeable to oxygen, as packing for liquid or semi-liquid products which produce gas. When the plastic film is reinforced with a uniformly perforated second plastic film, the resulting material is suitable for the manufacture of packaging for the storage of liquid or semi-liquid products containing yeasts, such as cream yeast.</p> |