What is meant by ‘extract’ when referring to wines?

The ‘extract’ consists of all the complex compounds that give the wine its flavour. Wine consists mostly of water, plus about 13 per cent of alcohol. Then there are the actual flavourants obtained from the grapes. In a light-bodied, thin-ish wine you would expect to find about 18 grams per litre of extract.

. A white wine with any more than about 22g/l would be quite a full-bodied, serious drink. A full-bodied, heavy red wine might contain up to 30g/l of extract. You could call the extract a measure of the concentration of flavour in a wine.