Perfectly ripe, clean bunches of grapes are harvested and placed in former tobacco kilns to partially dry the berries leaving us with concentrated fruit. Using this process it can take days or even weeks to decrease moisture in the berries. When the desired dehydration levels are achieved, the fruit is taken from the kilns, destemmed and crushed to reduce the extraction of green tannin during fermentation to a minimum.
Grapes are allowed to dry in a process called rasinate (to dry and shrivel) in Italian which concentrates the sugars and flavors and is similar to the production of French Vin de Paille.
The quality of the grape skin is a primary concern as that component brings the tannins, color and intensity of flavor to the wine. The process of desiccation not only concentrates the juices within the grape but also increases the skin contact of the grapes. At the end of the drying period, a number of complex transformations will have taken place. The grapes lose around half of their original weight through evaporation, increasing the concentration of sugar to around 25%-30%. There is a reduction in the level of acidity and change in the ratio of fructose to glucose which favours the concentration of polyphenols and a significant increase in the amounts of glycerine and other components which make Appassimento completely different to wines made in the normal way with freshly-picked grapes.
The most evident consequence of the drying process is the loss of weight: 35 to 50%. Following drying, the grapes are crushed and go through a dry low temperature fermentation process which can last up to 50 days. The drying process also leads to an increase in the amounts of a substance called resveratrol, to which authoritative international research has attributed the beneficial effects of moderate wine drinking.
"Drink wine, and you will sleep well. Sleep, and you will not sin. Avoid sin, and you will be saved. Ergo, drink wine and be saved."
- Medieval German saying