Losing as much as Rmb800 ($116) on every tonne of soybeans crushed, 430 plants went bankrupt and the government opened the longprotected sector to foreign investors.

Noble rushed in, snapping up crushers in the city of Chongqing, Shandong and Guangxi provinces, and Nantong in Jiangsu province.

"We bought [the Nantong crusher] in [the] bankruptcy court," Mr Elman said, noting that in doing so Noble had to fend off the likes of Cargill of the US.

"You can't have better credentials [with the local government] than that. It was a very transparent process, very simple."

So-called "crush margins" recovered almost as quickly as they had collapsed and the door was again shut to foreign investors.

But Noble was safely in and today accounts for 10 per cent of soybeans crushed in China.

Only Wilmar, controlled by the family of Robert Kuok, the Chinese-Malaysian tycoon, and state-owned group Cofco have a bigger presence in the market.

Between 2005 and 2007, the market share of China's leading seven soybean processors increased from 56 per cent to 65 per cent.

The economics of Noble's soybean pipeline are compelling.

It sources in Brazil and Argentina, where production costs are 25 per cent cheaper than the US.

Brazilian farmers can also produce as many as three crops a year, compared to just one in North America.

At the other end of the pipeline, operating costs at Chinese crushers are 40-50 per cent cheaper than in Brazil and the US.

According to the investment bank JPMorgan, soybean prices in China are about 40 per cent higher than international market prices, reflecting keen demand for the bean and its derivatives in a country where imports account for three-quarters of domestic demand.

As China's population grows richer and incorporates more meat into its diet, so too does the demand for soybean meal as an animal feed.

"One of the world's big problems is turning carbohydrates into protein," said Mr Elman.

"One used to grow grains to feed people. Now we grow grains to feed animals."

Unfortunately for Noble, it is not quite as easy as buying low and selling high into the world's biggest soybean market.

Diego Barbero, in Singapore, the head of Noble's grain and oilseeds division, notes that crop purchasers must frequently play cat and mouse with farmers, who naturally want to hoard their soybeans until prices are surging.

Volatile markets also mean prices can fluctuate widely during shipping and processing.

Noble seeks to manage these risks through hedging and leasing agreements with farmers.

"It's all about managing the trade flows," said Mr Elman.

"Volatility is good if you are a speculator, but it makes it extremely difficult to manage a business."

Copyright The Financial Times Limited 2008