This process, also known as acidification or acidification, is the enrichment with different acids. This is useful when the grape must has too little acidity in hot years or in climatically warm wine-growing regions. This is a frequently practised procedure in many countries of the New World. According to EU law, this is generally permitted for fresh grapes, grape must, partially fermented grape must, young wine and wine. However, this depends on the wine-growing zone.
For wine-growing zones A (Germany, except Baden) and B (Germany-Baden and Austria), however, acidification is not permitted or is only permitted in exceptional cases after an appropriate application (however, deacidification is very much permitted). Malic acid, metatartaric acid, tartaric acid or citric acid may be used. A common form, especially in southern countries, is to blend low-acid wines with high-acid wines.