After launching its first shipment of directly imported US wines into China, Amazon China, Amazon.com's branch there, said the wines have received a very good response in the country, especially in Shanghai.

"The direct-sales model gives our wines quality assurance and more cost-effectiveness," said Niu Yinghua, vice-president of Amazon China. "Consumers can easily have fine wines from thousands of miles away to by clicking Amazon.cn."

According to Amazon China, sales of its wines in Shanghai account for nearly half of its total sales, making Shanghai the hottest selling city in China.

Barbara Insel, president of Stonebridge Research Group, a leading research firm for the wine industry, said the news from Amazon China is good news for all California wines, as it shows that there is interest in and demand for fine wines from California's family producers.

"Several wine experts in China said that wine consumers in Shanghai were the most knowledgeable and confident and therefore would be the most open to trying new wines. Unlike perhaps less experienced consumers, they know better than to think wine had to be French to be good or admired," Insel said.

"Amazon's experience proves that advice to be true," she added.

Amazon China has partnered with seven US wineries, most in California, to sell wines on its website since September. All selections are made from grapes sourced from low-yielding, high-quality vineyards and priced between $20 and $65 a bottle.

"China is one of the markets we sell to who love Andretti Wines," said Joe Antonini, chairman and co-founderof Andretti Winery, one of the seven wineries whose products are sold on Amazon China.

Founded in 1996 by Formula-1 racing driver Mario Andretti, Napa Valley-based Andretti Winery sells cabernet sauvignon, merlot and chardonnay on Amazon China. "Those three are great sellers," Antonini said. "The Chinese love our wines."

For the first six months of 2013, California's wine exports to China totaled nearly $34 million, up 7 percent from the prior year.

The state's wine shipments to the Chinese mainland have been on a decade-long upswing, starting from a modest $3.4 million in sales in 2002 to $74 million in 2012.

Liz Thach, professor of wine business and management at Sonoma State University, said the high quality of California wines with bright fruit-forward flavors are very appealing in China and should continue to gain traction there.

"We are also starting to see some wineries in Napa being purchased by Chinese," Thach said. "I believe there is a positive relationship between China and California, and that an increasing number of California wines will most likely be exported to China in the future."

Thach believes that Amazon China is providing another channel for California winemakers who are trying to enter the China market.