Containers made of this material are used as an alternative to oak wood, stainless steel or natural stone (granite) for fermenting and storing wines. The conventional concrete containers are mostly lined on the inside with glass tiles or stainless steel sheets, more rarely with plastic or coated with varnish. The advantages are optimal use of space, flexible volumes and low shrinkage. Since the mid-1990s, experiments with egg-shaped concrete containers have been carried out, starting in France and then in Spain and now also in Germany. In the German wine-growing region of Franconia, some winegrowers are using such "concrete eggs" with a volume of 900 litres.
As with wooden barrels, there is little contact with oxygen, which can be roughly compared to micro-oxygenation. To prevent the acidic wine from reacting with the cement surface, the containers are treated inside several times with tartar paste before filling. Compared to wood, a possibly undesirable wood tone (toast aroma) is avoided. Due to the unusual shape, the wine is constantly in circulation; there is no blind spot. The wines aged in them are said to have more intense aromas. Similar results are achieved with containers made of granite. Such containers are often used for Orange Wines. See also under fermentation tanks as well as lists of relevant keywords under barrel and barrel types.
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Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)