Many people are still unaware of the reason why the bottom of bottles is concave.
Old-fashioned winemaking techniques lacked today’s advanced filtration methods. As a result, yeast deposits and residues would build up in the bottle, sometimes making the wine cloudy.
The hollow base offered a simple but effective solution. By creating an area where sediment could settle, it isolated it from the rest of the wine. Thus, when served, the poured wine remained clear, preserving its elegance and flavor, without any visual disturbance.
A question of manufacturing and… profitability
In the days of the first glass bottles, producing a perfectly smooth base was a technical challenge. Glassblowing often left irregularities, particularly at the base. Rather than combat this phenomenon, artisans made it a standard: by hollowing out this famous cavity, they reinforced the strength of the bottles while simplifying their manufacture.
And for the tavern owners, this detail had another advantage: a slight reduction in the actual volume of the wine, almost imperceptible , but very useful for serving a little less without it being too noticeable ! A trick that has undoubtedly survived through the ages…