Officials at the U.S. Food and Drug Administration said to remember the 2-Hour Rule: Discard any perishables left out at room temperature for more than 2 hours, unless hot food is kept at an internal temperature of 140 degrees F or warmer and cold food is kept at 40 degrees F or colder.
"If planning a buffet at home and you are not sure how quickly the food will be eaten, keep buffet serving portions small. Prepare a number of small platters and dishes ahead of time, and replace the serving dish with the fresh ones throughout the party," a statement by the FDA said.
"Don't add new food to an already-filled serving dish. Instead, replace nearly-empty serving dishes with clean freshly-filled ones. Be aware that during the course of the party, bacteria from people's hands can contaminate the food. Plus, bacteria can multiply at room temperature."
Do what restaurants and grocery stores do, use a food thermometer often to check the temperature of food, the FDA advised.
"Be aware that some warmers only hold food at 110 degrees F to 120 degrees F, so check the product label to make sure your warmer has the capability to hold foods at 140 degrees F or warmer," the FDA said. "This is the temperature that's required to keep bacteria at bay."