New test to judge the quality of corn DDGS
DDGS are the co-product of dry-milled ethanol production and are used as a feed ingredient to provide supplementary energy and protein.
To date, the industry had lacked reliable tests to judge the quality of corn DDGS during the process of raw material reception, said Evonik. It developed this tool to close that gap in the market.
The testing process is very easy as it is based on NIR-technology, an Evonik spokesperson told us.
“Locally the user grinds a sample of DDGS and takes a NIR scan. The spectra files are uploaded via Evonik’s AMINONIR Advanced Application for central evaluation. The results will be available within three to five minutes.”
The analytical tool distinguishes over-processed batches and reveals the degree of over-processing, which is a major concern in corn DDGS, said the company.
Over-processing has a negative impact on the nutritional value of DDGS as the amino acids are destroyed and amino acid digestibility is lowered, it added.
Over-processing of DDGS can occur during drying, the critical step in the production of DDGS, said the Evonik representative. In most cases, rotary drums are used for drying and applied drying temperatures vary a lot between different plants, he explained. Such variation has a direct impact on the nutritional value of the feed ingredient. Up to 20 percentage points difference had been reported in digestibility levels.
“Drying temperatures between 127 to 593°C (260 and 1100°F) have been reported. For example, Stein et al. (2006) had a closer look on the nutritional quality of DDGS samples from 10 different plants. They reported that the Lys digestibility for pigs ranged from 43.9 to 63%.”
This factor usually results in nutritionists applying high safety margins to corn DDGS and using low digestibility coefficients, to minimize risk, said Evonik.
It said its analytical service allows separate calibrations for ground and unground material. This includes calibrations for unground material when immediate results are requested, for example for incoming material on a weigh-bridge. When producers require a more precise analysis, such as for feed formulation, calibrations for ground material can be chosen, it added.
The new calibrations are up-to-date regarding sample quality and variability on global basis, said the supplier.
US tops corn DDGS producing countries
DDGS is a by-product of grain-based production of ethanol. In 2017, global ethanol production reached 27.05 billion gallons (102.5 billion liters), according to data from the US Grains Council (UGC).
The US is the dominate producer of ethanol with a market share of about 58%. Brazil is the second largest producer of ethanol (26%) but the production is based on sugar cane and not on corn like in the US, noted the RFA Ethanol Industry Outlook, 2018.
The UGC data shows that, combined, US ethanol plants possess the capacity to produce more than 15 billion gallons of ethanol and 44 million metric tons of DDGS. About 70% of the American DDGS is used within the US.
DDGS exports from the US reached more than 11m tons in more than 49 countries in 2017/2018. Mexico purchased the bulk of DDGS exports, consisting of 18% of the export market, while South Korea (10%) was the second largest importer. Turkey (10%), Vietnam (9%) and Thailand (8%) round out the top five importers for 2017/2018, found the UGC report.
Ruminant feed takes up 78% of the DDGS produced. About 14% of it is used in swine feed and 7% in poultry feed, as per the RFA Ethanol Industry Outlook, 2018.
