Many beer makers sell or give grain leftover from the brewing process to farmers, who use it as feed for dairy cows and other animals.
The grain would be affected by new food safety rules being developed under the 2011 Food Safety Modernization Act.
U.S. Food and Drug Administration spokesman Dr. Dan McChesney says livestock feed is generally safe, but the agency wants to ensure brewers' grain is handled properly during the transfer from breweries to farms.
Brewers have worried the rule would add costs for testing, training and paperwork.
McChesney says the agency will take another look at the rule and clarify it.