Trace amounts of antibiotics in distillers’ dried grains with solubles (DDGs), a co-product from ethanol production, should not present any scientific concerns for the Food and Drug Administration (FDA), according to a recent study. To examine potential problems of antibiotic residues in DDGs in swine diets, Dr. Jerry Shurson, professor of animal nutrition at the University of Minnesota, tested 159 DDGs samples collected by independent nutritional consultants. Shurson said the ethanol production process renders the antibiotic biologically inactive. “Based on research information published in the scientific literature, the antibiotics being used in ethanol production appear to be inactivated due to the high temperatures and/or low pH that they are exposed to during ethanol and DDGs production,” Shurson reported.
Shurson’s research found very small levels of certain antibiotic residues in DDGs, but they generally had no biological activity when extracts were tested with sentinel strains of E. coli and Listeria monocytogenes. “The amounts of antibiotics used in ethanol production are well below the amounts that are approved by FDA for use in feeds,” he noted. Commenting on the issue, the American Feed Industries Association (AFIA) noted that the most recent study is the second survey showing very low level antibiotic residues in DDGs. Antibiotics are used by a segment of ethanol producers to protect bacteria from destroying the ethanol-producing yeast cells. FDA is reviewing some of these antibiotics for safety for use in ethanol production, AFIA added.
In discussion with AFIA, FDA has not asked these antibiotics to be removed but the agency is reviewing certain petitions for these products. This includes a review of any potential human toxicology impacts of such use. AFIA believes FDA has adequate authority to require removal from the marketplace any products that are not safe, including authority to ban the use of antibiotics in DDGs if there is an imminent hazard.