Focus on Biofuels: Quality control contributes to boost U.S. DDGS exports

The popularity of using U.S. dried distiller’s grain with solubles (DDGS) as a feed ingredient in dairy, beef, swine and poultry feeds has been increasing across markets worldwide. From Morocco to Indonesia to Saudi Arabia, many feed users are noticing the benefits of this economical, yet nutritional ingredient, a co-product of the ethanol- and alcohol-making process.

China is leading the way in imports, and received its second-ever bulk shipment of U.S. DDGS in early December 2009. According to the U.S. Grains Council, China imported 8,000 tons of U.S. DDGS in 2008. By the end of calendar year 2009, DDGS imports into China reached around 500,000 tons, reflecting more than a 6,000% increase.

There are many reasons why Chinese dairy, livestock and poultry producers find the product appealing, ranging from its color and appearance to its affordability and nutritional value.

Many DDGS purchasers buy based on moisture content and nutritional makeup, including starch, fat, fiber and protein levels. Spec sheets are often required to ensure the customer receives what they expect. Proper testing and instrumentation methods help ensure that ethanol producers deliver the quality and value their customers demand.

Testing for other parameters, such as the presence of toxins, is another main priority for ethanol producers. There is a variety of methods and instruments available to ethanol producers to reveal the makeup of their DDGS.

Nutrition testing
Most DDGS contracts specify the desired level of protein, fat, fiber and moisture, components that are collectively referred to as a nutritional profile.

Some importers do their own testing upon arrival of shipment to make sure they receive what’s stated in the contract; however, the shipper generally tests product before it ever leaves the plant to ensure it will meet those specs.

Perten Instruments, a supplier of analytical equipment, offers an instrument called the DA 7200 that can simultaneously analyze multiple nutritional components, including protein, fat, fiber, moisture, starch, sugars, ethanol, sulfur and others, using a near-infrared (NIR) spectrometer.

“The instrument tests for a complete nutritional profile,” says Wes Shadow, business development manager, Perten Instruments. “The purchaser needs more than one piece of information because the protein or fiber level alone won’t give them enough information to properly use it in their formulations.”

The DA 7200 can provide fast results by reducing the need for sample grinding or filtration of slurries, so the levels can be measured in about six seconds.

Moisture level plays an integral role in the value and profitability of DDGS.

“Though a simple measurement, moisture levels are critical,” says Shadow. “The plant must balance the energy costs of removing moisture with quality. High moisture levels can promote microbial growth and affect flowability. Overdrying or drying at too high a temperature costs the plant money and can damage the protein. Timely and constant monitoring is critical.”

The nutritional makeup is only one aspect of testing that’s done at an ethanol facility. As with any grain processing plant, the risk of toxins is ever-present and something facilities monitor closely.

Toxin testing
The presence of high toxin levels in U.S. DDGS is currently not an issue for Chinese importers, so there isn’t much U.S. DDGS testing conducted after it arrives in China.

“At the moment, China’s customs officials do not test imported DDGS for aflatoxin or other mycotoxins,” says Cary B. Sifferath, China senior director, U.S. Grains Council. “But they could change this in the future. If they do start to check for various mycotoxins, some believe they would use U.S. FDA acceptable levels for various mycotoxins.”

Generally, U.S. DDGS has fewer occurrences of toxins than domestic Chinese DDGS, due in part to the accurate and reliable testing methods employed by ethanol facilities in the United States.