BEIJING - China's Ministry of Commerce has decided to impose anti-dumping duties on distiller's dried grains (DDGs) from the United States by requiring importers to pay a cash deposit on purchase.

The domestic industry has been "substantially" harmed by the dumping of DDGs, the ministry said in its preliminary ruling following an investigation launched earlier this year.

Starting on Friday, importers of the product must place deposits with Chinese customs at 33.8 percent of the import value.

DDGS are the nutrient rich byproduct of dry-milled ethanol production, which are used in animal feed. China is the world's biggest buyer of DDGS, with most imports coming from the United States.