Withering, a technique used in the production of sweet and passito (raisin) wines
An ancient method (older than the Greeks), which every wine lover has heard of at least once. But how does the withering technique used to produce sweet and passito wines work?
Exactly what is the withering technique? It is a very widespread practice, of extremely ancient origin (some archaeological evidence dates it back to before the Ancient Greeks). This method originated with the aim of storing grapes for longer. The over-ripening of the grapes generates higher quantities of sugar, making it possible to eat them for a very long time after harvesting. By extension, wines made from these grapes have a much higher sugar content and much more pronounced aromas, as well as a greater resistance to ageing.
The withering technique
When we talk about the withering technique, we actually make a little mistake, or perhaps it would be better to say that we are slightly inaccurate. There are actually three techniques: on the vine, natural and forced.
What these variants have in common is the effect they produce: the withering process causes the grapes to lose part of their initial mass (particularly water), while simultaneously increasing their sugar concentration. The effect is a greater concentration of scents, colours and aromas, in the grapes first and then in the wine.
On the vine
Withering on the vine involves leaving the grapes to over-ripen directly on the vine: the grapes aren’t harvested at the usual time, but up to a month later. The period can also vary depending on the geographical location of the vineyards.
Withering on the vine is quite common in Apulia. The grape harvest in the case of over-ripening is known as a “late harvest”. This definition may appear on the label.
Under certain circumstances, Botrytis cinerea, or noble rot, can develop on the grapes, conveying intense scents and nuances to the wines.
Natural withering involves the normal harvesting of the grapes, which are placed on various types of racks (wooden crates, reed mats, metal netting or pergolas) and left to over-ripen naturally.
The bunches of grapes remain exposed to the air, and this activates the process that leads to the elimination of water and the concentration of sugars in the grapes.
Depending on where this process takes place, the exposure of the grapes can vary. In Southern Italy, for example, a mild climate and more sunlight allow the fruit to be left outdoors, whereas in northern regions, attics or lofts are preferred.
Unlike the natural method and the on-the-vine method, forced withering requires over-ripening to take place in environmental conditions regulated by man using conditioning systems that adjust the temperature, humidity and ventilation of the rooms.
The technology makes it possible to create the best environment for the over-ripening of the bunches in these rooms. The process of dehydration and concentration of the sugars is begun with a little help, hence the technique being known as “forced”.
Forced withering is very often used when environmental conditions make it impossible to obtain appreciable results in a natural way, whether due to climatic problems, harvesting problems or the organisation of the work of the winemakers.
Wine withering in the world
Wines made using withering techniques are currently generating considerable interest at European level. The markets that have shown greatest interest are undoubtedly those in Scandinavia (in terms of growth trend), particularly Sweden.
Germany holds the record in terms of consumption for passito or raisin wines. What seems to win wine-lovers’ hearts is the originality of these wines, which present unique aromatic characteristics and an intensity of fragrances and aromas of immense richness.
Dacastello presents Nero d’Avola Sicilia DOC Appassimento, from a native Sicilian grape which is one of those that best represents the island. Deeply Mediterranean in tradition, inspiration and suggestion, it draws a unique character, a rare aromatic harmony and a charm from the withering technique that wine lovers find it hard to resist.
Would you like more information about the withering technique or about our wines? Contact us and we will be delighted to answer all your questions!