According to official figures, the average wholesale price of live pigs in October was HK$10.40 per catty, more than 23 percent less than HK$13.6 per catty in January.

However, the retail price of pork in October was 2.2 percent more than in January, reports The Standard.

Questioned in the Legislative Council, Chow said the policy objective of the administration was to maintain a stable food supply and ensure food safety.

"Food prices should be determined by the free market. What the administration can do is to improve market transparency and enhance market efficiency so as to help consumers make a wise decision," Chow said.

Chow said there had been no unusual fluctuations in the auction price of live pigs since mid-January when the government made auction prices public.

However, the Consumer Council noted in August that there had been aggressive bidding by a few live pig buyers in a very small market.

"The report found that as a whole, the live pig bidding process was open with improved transparency in the live pig trade," Chow said.

But legislator Fredrick Fung Kin-kee said Chow's response was unacceptable and accused the official of not probing the problem sufficiently.

"Retailers always have their excuses. Chow has not further investigated or proved what is the main cause of the volatile pork retail price. I think the government is not sincere in trying to solve the problem," Fung said.

He also questioned whether the monitoring process was insufficient since some pig buyers were involved in aggressive bidding. Pork Traders General Association of Hong Kong deputy chairman Hui Wai-kin said comments by legislators were "unreasonable".

"There have been price adjustments since the wholesale price has stabilized, but a spontaneous cut or increase in retail prices is not possible. The legislators and officers have not studied clearly how the sector works. I am disappointed as their calls are totally unreasonable," Hui said, adding that the retail price of pork has dropped 30 percent from HK$50 to around HK$36 per catty since July.

However, as mainland pigs are to be tested for melamine in November, supply has been reduced and wholesale prices have shot up to around HK$1,400 to HK$1,500. Despite this the retail price has remained at around HK$36 per catty.