Experts are calling for more measures to prevent wastage in restaurants and at the family dining table, as Xu Wei reports.

As he sat in a seafood restaurant in Shanghai, Liu Yao was surprised to see more food going into garbage bags than was actually being consumed, but he was even more surprised that nobody seemed to care.

"They (the diners) were toasting each other, exchanging pleasantries and trying to charm each other. Eating was probably the last thing on their minds," said Liu, a researcher with the Institute of Geographic Sciences and Natural Resources Research at the Chinese Academy of Sciences. Liu took part in a research program into food wastage at restaurants in four cities - Beijing, Shanghai, Chengdu in Southwest China's Sichuan province, and Lhasa, the capital of the Tibet autonomous region.

He said the problem is especially severe in large restaurants because they are the usual venues for business discussions and networking events.

"The customers were only using dinner as a platform for negotiations. They didn't really care about the food itself," he added.

The research conducted by the institute found that diners at large restaurants wasted an average 130.19 grams of food, while those at fast food restaurants wasted 39.09 grams.

"The more high-priced or luxurious the restaurant, the more waste there is," he said.

By weighing the dishes before and after each meal, the researchers were able to identify a number of factors that could be responsible for wastage in restaurants, including age, gender, and the scale and the type of eatery. Based on research in the four cities, the researchers estimated that more than 25 million metric tons of food is wasted in the country's public catering sector every year.

Cheng Shengkui, the institute researcher who led the program, said wastage at official banquets has been curbed dramatically in the four years since the start of the official anti-corruption and frugality campaign. Meanwhile, the government-backed Operation Clean Plate, which encourages people not to order too much at restaurants and to eat everything provided, is also having an impact. However, that does not mean wasteful behavior and lavish dinners have been eradicated altogether.

A large number of business banquets at high-end restaurants have not been affected by the frugality campaign, and big restaurants are switching their focus from government-sponsored banquets to attract more trade from the general public, Cheng said.

He explained that Chinese etiquette requires hosts to provide large amounts of food for their guests. "If all the food on the table is finished after a banquet, it could be interpreted as the host not showing enough largesse," he said.

Cheng noted that food wastage was once prevalent among wealthy people, but the growth of average personal incomes has seen the problem spreading. "Now, it seems everybody is wasting food. People now take wastage for granted," he said.