BEIJING, April 3 -- Although the lunch rush is over, chefs at Quanjude Peking Roast Duck restaurant in central Beijing are still busy serving their famous poultry.

Roast duck, also called Peking duck, is famous for its crispy skin and tender meat. The duck is sliced in front of diners by the chef, and the meat is eaten wrapped in pancakes with scallion, cucumber and sweet bean sauce.

Established in 1864, Quanjude follows a tradition of using open wood-fired ovens to roast the duck until its skin is golden and crispy. The open oven roasting method was originally reserved for duck served in the imperial palaces.

Last year, Quanjude Group, founded in 1993, sold more than six million ducks and served nearly 20 million diners.

Wu Yubo, chief roast duck chef at Quanjude, said although many restaurants sell roast ducks, not all of them are high in quality.

"Quanjude has its own bases for raising ducks, and 30 processes are used in processing and cooking each duck. Also, franchise restaurants have the same standards for duck quality, slicing skills and attractive presentation on the plate," Wu said.

As a brand with more than 150 years of history, Quanjude is well aware of the challenges in the market, said Wu.

"The youth do not inherit their preferences from older generations but have their own taste," Wu added.

The chain has learned to adapt to changing tastes. In the 1970s, Peking duck was served as soon as the duck was taken out of the oven. However, in recent years, customers have preferred good presentation of duck slices on the plate.

When China was hit by bird flu a few years ago, Quanjude began to create new dishes, such as roast shellfish and lobster, to provide more choices for customers.

Before the reforms and opening-up of the 1970s, food was in short supply and people tended to have fatty meat, while today leaner meat is popular.

"We prolong the roasting time to let the duck fat melt to make it healthier," Wu said.

In order to take advantage of the e-commerce boom in China, Quanjude Group launched an online shop at tmall.com two years ago, and its sales have grown steadily.

The online shop sells roast ducks in gift sets as well as other duck products, cakes and snacks. Total online sales of roast ducks have reached 65,379 since the e-commerce site was launched.

"E-commerce is a trend in future sales, no matter if an enterprise is old or new," said a Quanjude marketing employee surnamed Liu.

Roast duck has become a symbol of Beijing and China.

Beshad Pajman from Iran eats at roast duck restaurants every time he visits Beijing. "The taste is special and watching the duck get sliced beside my table really makes me feel valued," he said.

In 2014, chefs from Quanjude served roast duck to nearly 700 guests at the national banquet in the Water Cube. The chefs also performed a live demonstration on cutting Peking duck.

Quanjude has five overseas franchise restaurants, including one in Melbourne, Australia that opened in 2008. They overseas branches use local ducks and ingredients as live poultry exports are forbidden.

"Next, we will inspect conditions in Italy and try to open more branch restaurants if possible," said Wu.

Zhou Huaishan, CEO of the China Time-honored Brand website, said that heritage brands like Quanjude inherit Chinese traditions and market local customs, which can boost tourism.

"They must be innovative and seize the opportunity of the Internet for greater development," he added.