Definition: Seventy-five centilitres (75 cl)

Why are bottles 75 cl and not 60 cl or 1 litre?

This is a question that seems basic and obvious, yet few people know the answer.

The main reasons can be found in current European legislation. Since 1974, European legislation has harmonised the "nominal quantities" for bottling, i.e. the authorised volumes. The current directive dates from 2007. It authorises eight different volumes, ranging from 100 ml to 1.5 litres, including 0.75 litre and 1 litre bottles. But if 1 litre bottles are authorised, why do we insist on using a 0.75 litre standard? The reasons are no longer legal, but historical and practical.

Abbreviated to 75 cl, this is the standard capacity of a wine bottle.

This 0.75 litre standard facilitated exports to England, at the time one of the main markets for French winegrowers. Jean-Robert Pitte, geographer, former president of Paris IV Sorbonne and author of several books on wine, explains:

"0.75 litres is one twelfth of an English double gallon (symbol: gal GB or gal Imp) - an Anglo-Saxon unit of measurement corresponding to 4.5 litres. The 0.75 litre capacity seems to have been invented in Bordeaux for the purpose of trading wine with England in cases of twelve."

This also made it easier to transport wine, explains Jean-Marc Bahans:

"At the time, the capacity of ships was calculated in barrels. A Bordeaux barrel held 900 litres. If you divide 900 by 0.75 litres, you get 1,200, or one hundred cases of twelve bottles. As is often the case, the origin can be found in customs."

Legislation and historical reasons for exports from Bordeaux to England: there's your answer!

As for the names of the large containers, most of them are those of kings of Israel.

In other words:

A case of 12 bottles represents 2 imperial gallons and a 225-litre barrel represents 50 imperial gallons.

The imperial gallon (symbol gal GB or gal Imp) is equal to 160 fluid ounces in the imperial system of units, or exactly 4.54609 x 2 = 9.09 : 12 = 0.75 litres.

The jar shown in one of the photos has a capacity of one imperial gallon, or 4.54609 litres.