Term (in Germany the form "Brüderschaft trinken" is more common) for the widespread custom in many countries of switching to the familiar form of address "Du", preferably with a glass of wine or sparkling wine (but also other alcoholic beverages such as beer or schnapps). This is usually proposed by the older person or, in the case of a mixed couple, by the lady. Today, people drink from one drinking vessel each. The arms holding the vessel go through the crook of the other person's arm. After taking a sip, they give each other a kiss, either on the cheek or on the mouth, depending on their confidence. Then one introduces oneself with the first name. It is possible that brotherhood drinking has its origins in the custom of toasting, which was widespread in the Middle Ages. The person who wanted to offer the brotherhood to someone would address him and drink to him. The cup was filled again and then the person addressed drank from it.
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)