Asti is a unique Italian sparkling wine produced in the south-eastern area of Piedmont. With a particular focus around the two towns of Asti and Alba. Since 1993 the wine has been classified as D.O.C.G. and is one of Italy's largest producing wine appellation. Asti is very important to the Piedmont region, producing on average around 5-6 times the volume of the more well-known Barolo red wine.
Asti is crafted from the Moscato Bianco grape varietal, and is typically a sweet sparkling wine, low in alcohol and often served as an aperitif or with fresh desserts. Asti sparkling wine is not made through the use of secondary fermentation inside the bottle - but from a delicate 'single' tank fermentation method.

 

Another sparkling wine called Moscato d'Asti is made in the region from the same varietal, but only slightly sparkling (frizzante) and is also low in alcohol 5.5%. The fermentation process is stopped earlier than Asti, retaining sugars and resulting in a lower level of alcohol.
The Moscato Bianco grape varietal has a long history in Piedmont along with Nebbiolo, being one of the oldest grape varietals in the region. However, the production of sparkling Asti is relatively recent, with the first sparkling Asti believed to have been produced around 1850 by Carlo Gancia who studied the Champagne method.  
Asti can be made in the same traditional method used for Champagne - where the wines undergo a secondary fermentation in the bottle. Though today, typically they are made in a larger, more commercial method, in which the wine is allowed to go through fermentation in a large stainless tank. Since the 1950’s the increasing demand made many producers turn to bulk wine production using the 'Tank Method' which makes the wine sparkling through a closed fermentation in a tank versus a secondary fermentation inside the bottle. When the wine was promoted to DOCG status in 1993, producers decided to distinguish themselves and improve their reputation and dropped the use of 'Spumante' in favour of the name Asti. Along with the change in name, a change in style; with several producers creating more modern styles of Asti that are less sweet, retaining natural fruit acidity and having more ripe fruit flavours. Recently some Asti winemakers have again taken to producing their wines in the Method Traditionnelle or Champagne method with secondary fermentation in the bottle.

Under Italian wine laws, Asti D.O.C.G. must be made from 100% Moscato Bianco, with grapes harvested at yields not greater than 10 tonnes / hectare. The finished wine must be fermented to a minimum alcohol that varies depending on the vintage, between 7% - 9.5% Alc/vol.
After the grapes are harvested, they are crushed and pressed, with the must transferred to large tanks where the temperature is lowered to near freezing in order to prevent fermentation starting. The tanks are sealed, pressurized and then the temperature is increased to allow fermentation to begin. The cooled grape juice is brought to temperatures around 20°C, which triggers the alcoholic fermentation with specific yeasts selected for special characteristics. Within the tanks the carbon dioxide by-product of fermentation is trapped, dissolving into the wine and creating the steady stream of bubbles.
Fermentation is allowed to continue until the wine has reached between 7% - 9.5% Alc and between 3-5% residual sugar and a pressure of 5-6 bars (about 80psi). The wine is then chilled to stop fermentation before being sent to a centrifuge that filters and removes all yeast from the wine to prevent fermentation from resuming inside the bottle. The wine is then bottled, labelled and shipped. The patron saint of Asti is the ‘San Secondo’ horse that can be found on labels as a seal of quality. Most Asti is not vintage-dated, however the large consumption and quick turnover of the wine suggests that the current wines on the market are from the most recent vintage. Asti is typically a sweet style of sparkling wine, with over 50g/L of residual sugar. So serve it well chilled, and look to pair it with fresh fruits and desserts - enjoy.