"Puttony" is a wooden cask originally used to collect harvested grapes with an estimated capacity of 22-23 kgs. Practically it was also used to measure the aszú berries added to the base wine, resulting in the traditional categorisation of Aszú wines. Before the Tokaj wine laws changed in 2013, Aszú wines were categorized from three to six puttonyos: the same number of puttonys of botrytised grapes would have been added to each Gönci cask of base wine (136 litres), resulting in the 6 puttonyos being the highest category with a 1:1 ratio. The sweetness and the depth of golden colour and aromas together with the acidity increase in line with the increase of puttony numbers.
The categorisation before 2013: a 3 puttonyos Aszú had from 60 to 90 grams of residual sugar per litre, a 4 puttonyos had from 90 to 120, a 5 puttonyos from 120 to 150, a 6 puttonyos from 150 to 180, an Aszú Eszencia from 180 to 450, and an Eszencia from 450 to even more than 800 grams of residual sugar per litre.
However, in an effort to simplify the wine labels, since 2013 Tokaji Aszú is no longer required to be labelled in “puttonyos”. Today all aszú wines from 120 grams of residual sugar up to 450 grams are simply called “Aszú”. Despite this, many wineries continue to use the 5 and 6 puttonyos categories to name their wines, helping customers figuring out the concentration level they should expect.