Definition: Chemical processes (on wine)

On the contrary, other products such as colourings are prohibited. The logic behind this is to ban products that are dangerous to consumers. For example, glycerol can give a thin wine the body it lacks, with a mellow taste; it is therefore tempting in cold countries (e.g. the glycol scandal in Austria).

Safe but misleading for consumers, and therefore prohibited: producing a so-called vintage wine by blending wines from different years. The exception that proves the rule is that this practice is permitted for non-vintage champagne.