SHANGHAI (AFP) - Starbucks opened its largest cafe in the world in Shanghai on Wednesday (Dec 6) as the US-based beverage giant bets big on the burgeoning coffee culture of a country traditionally known for tea-drinking.

The opening of the sprawling, two-storey outlet in a busy central shopping district was thronged by hundreds of customers, some waiting more than an hour in long lines stretching outside for a block in scenes reminiscent of a hyped-up new iPhone release.

The cafe spans 2,700 square metres - nearly half the area of a soccer field - and is the company's second Starbucks Reserve Roastery, a larger type of store featuring premium coffees, teas, and coffee-infused beer along with a personalised barista service.

The first roastery outlet opened in Starbucks' hometown of Seattle in 2014.

Starbucks already has more than 3,000 of its standard cafes in 136 Chinese cities, including more than 600 in Shanghai alone, the largest number of stores in any city in the world.

A new Starbucks opens every 15 hours in China, the company says.

Chairman Howard Schultz told Bloomberg News on Tuesday ahead of the store's opening that China was on course to become the company's largest market in less than a decade.

"It's obvious to us that the holding power of China for Starbucks is going to be much more significant than the holding power of the US," he said.

The store has a "Willy Wonka" feel, with a giant two-storey cask holding tons of freshly roasted beans that are sent out to the cafe's various bars via tubing that snakes along the ceiling, while packaged beans wander around on conveyor belts.

Zhao Fei, a paper trader, said drink prices running up to 78 yuan (S$16) for some coffees would scare off many Chinese customers.

"But many people in China are really starting to appreciate expensive coffees, especially young people in big cities," said Zhao, who nonetheless opted for a nitrogen-infused fruit tea.

"And it looks so wonderful here, many people will come just to look."