"We are committed to changing the information asymmetry of produce on the market. People have a mania for crabs from Yangcheng Lake, and are unaware of crabs from other areas that are equally tasty and nutritional," said Lelfie's Vice-President Jiang Zhengwen at a news briefing on Aug 24.

Some experts have also urged consumers to buy crabs from other areas - especially breeding grounds in Jiangsu province such as Hongze Lake and Tai Lake, and Poyang Lake in Jiangxi province - and not to become fixated on produce from Yangcheng Lake, partly because some retailers sell hairy crabs that are purported to be from Yangcheng Lake, but aren't.

In 2013, the trading volume of e-commerce in fresh produce and seafood in China totaled 13 billion yuan, a year-on-year increase of 221 percent. This year, the figure is projected to reach 26 billion yuan, a rise of 100 percent, the Economic Daily reported in August.

Wang Xiaoxing, an e-commence analyst with the Beijing-based consultancy Analysys International, says the e-commerce system for fresh produce and seafood in China is still at the stage of investing, financing, and creating new markets.

"Few of the e-commerce companies in the fresh food sector have made a profit as yet. Many online grocers are pondering their next move by conducting promotions and advertising," he says.

According to Wang, a major challenge facing e-commerce outfits in the sector is the high cost of cold-chain logistics. "In Beijing and Shanghai, some online food firms have their own cold warehouses to achieve fast delivery. But to reach smaller cities and the central and western parts of China, most online food firms and suppliers have to choose third-party cold-storage logistics, which is usually Shunfeng Express."

Wang says that despite the large amount of advertising being undertaken, the actual transaction volume of fresh items is still very limited, and that the demand for fresh produce and seafood online is low.