Chinese bubble tea chain Nayuki's shares tumbled on their Hong Kong debut Wednesday after the firm's IPO raised more than $650 million and made billionaires of its co-owners, who founded the company on a blind date.

The company joins a handful of bubble tea outlets to go public in recent years as the beverage -- which comes loaded with milk, sugar and tapioca pearls -- storms out from its Asian fanbase to gain a global following.

It also makes it the latest Chinese business to list in Hong Kong, even as a series of tepid performances by new companies spark concerns about the city's IPO market.

Targeting well-heeled young consumers, the 560-store chain opened its first outlet in the southern metropolis of Shenzhen in 2015.

Entrepreneur Peng Xin, 33, reportedly pitched her business idea to 42-year-old Zhao Lin -- a professional in the food industry -- over a blind date two years earlier.

Within months, the pair married and became business partners and now, with the firm valued at $4.38 billion, they are now each worth about $1.2 billion, according to Bloomberg News.

"It wasn't a reckless decision," Peng said in an interview with Bloomberg. "We spent almost two years testing our drinks on the street before opening our first store."

"Our family and friends were worried about us at the time," she said, having used their home as collateral for a loan. "But we and our team believed in our choice."

Nayuki said it will use cash from the share sale to embark on a massive expansion drive
Nayuki said it will use cash from the share sale to embark on a massive expansion drive AFP / Noel celis

The brand prides itself on innovative drinks, fresh ingredients and a cool cafe decor to set it apart in China's crowded bubble tea environment.

But the firm's first day on the trading floor did not go according to plan, plunging more than 15 percent at one point in one of the worst debuts in the city this year.

Shares in the firm recovered slightly but still finished at HK$17.12, more than 13 percent down from the listing price of HK$19.80.

Reports said the losses were fuelled by concerns about its high valuation and earnings outlook -- it clocked up losses of 203 million yuan ($31.4 million) last year as it embarked on an aggressive expansion drive, though revenue grew nearly a quarter.

The company plans to use the $656 billion raked in from the IPO to open 650 more stores this year and the next.

The rapid scale-up has drawn comparisons to embattled chain Luckin Coffee -- which burned through millions of dollars to challenge dominant US titan Starbucks before facing a raft of scandals.

However, research firm China Insights Industry Consultancy estimates the country's appetite for freshly made tea drinks will rocket threefold to US$53.2 billion by 2025, said Nayuki in its prospectus.

"I drink bubble tea a lot if I'm especially stressed, consuming eight to 10 cups a week," said one student at a Beijing store.

Another consumer in her 20s surnamed Li told AFP: "I try to control myself, but I end up coming about once or twice a week."