The year 1443 was a catastrophic year for Viennese viticulture. The wine was so extremely sour that allegedly even the iron tyres of the barrels were attacked. In the Viennese vernacular, the term "Reifbeißer" was therefore created (this name for sour wine is still valid today). The wine could not be drunk and was therefore poured onto the streets. Emperor Frederick III (1415-1493) then forbade the "throwing away of God's gifts" under the threat of severe punishment and ordered the undrinkable wine to be used for slaking the lime and making the mortar for the extension of St. Stephen's Cathedral in Vienna. However, this was more than just an embarrassing solution, because the addition of wine causes the formation of the almost insoluble calcium tartrate (which of course was not known at the time). This greatly increases the mortar's resistance to damaging chemical influences. Many sources report that the use of wine in the production of mortar was quite a common practice in Wien and the surrounding area at that time. In the wine-growing community of Falkenstein in the Weinviertel (Lower Austria) there is an educational wine trail. One of the exhibits is a wine barrel on which the tyres are cracked. A plaque mentions the term "Reifenbeißer" and the year 1456. The Falkensteiner of this vintage was also extremely acid, that it may also have been used for a mortar. See also under wine-growing customs.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)