Tsui Hang Village restaurant chain, which celebrates its 40th anniversary this year, hopes to cash in on the nostalgia for the next few months by reintroducing dishes from its original dim sum menu, including barbecue pork and pork lard rice, steamed pork dumplings with quail egg and pork liver, and black sesame rolls, nicknamed because they look like a roll of film.

"Going out for dim sum used to be a big deal," head dim sum chef Lee Kam says, reminiscing about the restaurant's early days. "People were not as wealthy then so it was a big treat. And people didn't usually order dessert, either; if they ordered one, in particular the black sesame rolls, they savoured every bite. That's why people would unroll it into a long strip and then eat it slowly in sections."

Lee, 65, was lured out of retirement to help oversee dim sum operations at Miramar Group, which owns Tsui Hang Village.

The jovial Lee has been in the business since he was 13 years old, and his career has included stints in Japan, Toronto and Shanghai. He has seen many changes in tastes and the way the food is prepared over the years.

"When I started working in the kitchen, we had to make everything from scratch by hand, but nowadays a lot of it is made with machines so chefs these days have it easier. But for dishes like the black sesame rolls, we still make that by hand otherwise it doesn't have the right texture," he explains.

The steamed pork dumplings with quail egg and pork liver was a popular dish more than 20 years ago.

"Back then, quail eggs weren't expensive, although the dish was labour-intensive as it required cleaning the liver thoroughly before steaming it."

Now that quail eggs cost more, restaurants are less inclined to put the dish on the menu, Lee says. But by bringing back these classic dishes for the anniversary promotion, parents and grandparents can share favourites they ate when they were younger with their children.

Betty Leong Sin-ling, head of investment property at the MTR Corporation, says they have found that diners prefer more authentic tastes and this has influenced which restaurants they will rent units to in the company's shopping malls.

At Elements, Tim's Kitchen and Pak Loh Chiu Chow Restaurant were chosen for their traditional dishes.

While Tsui Hang Village has evolved with the times and come back full circle, albeit temporarily, traditional restaurants like Yung Kee strive to keep things pretty much the same.

Last year, the venerable establishment on Wellington Street marked its 70th anniversary, and Yvonne Kam Kiu-yan, granddaughter of founder Kam Shui-fai, brought back some classic dishes that hadn't appeared on the menu for decades.

Many of her friends were surprised to discover the restaurant had plenty of other old-school dishes on the menu other than roast goose, making her realise she needed to do more to promote Yung Kee's other signature dishes.

One is called Jinhua ham with steamed tofu. The presentation of the dish is novel - a large piece of cured pork has several golf ball-sized holes scooped out and filled with round pieces of tofu before being steamed.

"It is based on a dish that author Jin Yong wrote about in his novel ," Kam explains. "A few years ago he wanted to host a banquet in Taiwan and asked us to help make some of the dishes in the story. We did lots of research and had to use our imagination and a lot of trial and error because some of the dishes didn't exist, including this one," she says.

"Previously, we would introduce new dishes periodically, but these past few years we have been going back to basics."

Dishes such as stir-fried mullet stomach with preserved olives, and sautéed prawns with fruit can be labour-intensive, which results in slimmer profit margins, Kam admits.

"Not many people are cooking these dishes any more, but they are part of Hong Kong history. We need to pass on these dishes to the next generation."

As Lee and those of his generation retire in the next few years, however, the skills and experience needed to prepare these traditional dishes could be lost. Asked what will happen when Yung Kee's chefs leave, Kam says they will deal with it when the time comes.

Lee says the younger generation are not be as knowledgeable about preparing these dishes because they learn in vocational schools not by completing an apprenticeship with a master chef.

"We'd wake up at two or three in the morning and then start making dim sum for the early customers," he recalls. "For , you need to make the first thing because you can tell if it's not fresh. Once it's made, then you can start stuffing the buns.

"There are some younger chefs who can cook, but not as well as us. The younger ones haven't been through the same training. They may know how to make the dim sum, because we have trained them, but how it tastes is another story," he says with a chuckle.

Another reason is that not all master chefs pass down their culinary secrets; when this happens things will inevitably be lost, Chan says.

"With Western dishes, you can easily find recipes for them. For traditional Chinese food it's harder. Vocational schools should teach students how to make dishes from scratch and make the recipes available because they are a part of our culture," he says.

He also believes fast-paced lifestyles have affected food quality as people resort to more processed food and do not have the time and know-how to cook home-style dishes.

"When I was young, my mother cooked out of necessity because we were poor. She used to go to the traditional Chinese grocery store and buy preserved vegetables to make steamed minced pork. But these kinds of shops don't really exist any more - and would a young person do that these days anyway?

"It's a pity to lose these dishes, but in the past 10 to 15 years we have come to know more about different cuisines. We didn't know about Spanish food or tiramisu back then. Now, cooking has become a hobby not a necessity. People take cooking classes or buy cookbooks to learn how to cook. They might prepare a steak or bake a cake more to impress their loved ones."

Nevertheless, Chan appreciates how some Chinese restaurants are trying to preserve these memories with old recipes.

"You can't do one without the other. Food is a very emotional thing. You like certain things because they bring back good memories and vice versa. Some people hate sweet potato so much because they ate it every day for several years during [the second world war] because they couldn't afford anything else. Some people like certain dim sum because they ate it with their parents. When we are young, we keep going forward, but when we get old, our lives are based on memories. When you get older, you miss your worry-free childhood."