cheeses which have been treated or cured by biological agents such as moulds, yeast or other organisms which have caused a visible crust to form on the surface of the cheese. The effects of the treatment or curing must extend visibly from the surface towards the centre of the cheese. The fat content by weight of the dry matter shall not be less than 50 %. The moisture content by weight of the non-fatty matter shall not be less than 65 %.