in the antique Rome, a very popular, syrupy grape syrup, which is obtained by boiling unfermented grape was made on a small fire. These were among other vessels from lead used, which gave the drink a sweet taste and juicy texture and also contributed to the preservation, but of course the health was very detrimental. According to reports of some authors like Pliny the Elder (23-79) was the grape must in half, after Varro (116-27 BC) and Columella (1st century AD) even thickened to one third of the original volume (probably there was different application). This thickened must was also fermented, resulting in heavy and sweet wines.
Defrutum was also used to improve the taste of thin wines. Similar products were Caroenum with a little less volume reduction and Sapa. After the ancient models, the popular until the 18th century Firewine, Traditionally, Italy is still considered today Vino cotto designated wines produced for private consumption. See also below must as concentrated grape must,