A picture shows Georgia's traditional vessel known as quervi in winemaking. [Photo provided to China Daily]

Georgia's winemaking is rooted in a traditional vessel known as quervi, an immense clay or cement jar more than 2 meters tall and stored underground. While modern winemakers here also produce wines aged and fermented in stainless steel and wood, quervi wines are a source of great pride and many of the country's hippest wine bars offer them exclusively.

The process gives all of the wines－both reds and whites－a lot of tannic structure, notes Debra Meiburg, the Hong Kong-based master of wines who has organized our tour.

"That has really made me reconsider the way we think about wines," she says. "Who decided, for example, that red wines should be tannic and white wines should not be?"

Tannic whites are alien to most wine drinkers, especially in the West, and take some getting used to. Our group embraces the reds very readily, though we're fascinated by the unusual whites and eagerly sample them.

No wine tour in Georgia is complete without a visit to a quervi maker. We meet one in a little village in the Khaketi winemaking region. Zaza Kbilashvili walks us through the process as he shows us his kiln and his curing house, where the finished egg-shaped urns are stored for several months to harden. The inside surface is sometimes lined with beeswax, while the exterior is traditionally covered with a lime-based mortar before burying.

One of the best parts of that visit: Watching an adult man climb down into a 3-meter-tall quervi to clean it. That must be done each year before the grape harvest, using sulfur vapors, herbal cleansers, water and a brush made of cherry bark.