How to Keep Hot and Cold Foods at the Correct Temperatures at Your Next Cookout

As the weather heats up, there's a good chance you have cookouts on the mind. The summer after all, is prime time for hosting outdoor parties complete with fresh salads, grilled corn, and juicy homemade burgers. But before you start brainstorming that perfect summer menu, it's important to brush up on your food safety skills. This includes knowing how to store food at the right temperatures, which will keep illness-causing bacteria off the guest list.

"Protect your delicious meals by keeping food out of the temperature 'danger zone,' [which is] between 40°F to 140°F," says Jessica Green, MPH, RDN, CSOWM, CP-FS, registered dietitian and certified food safety professional. This temperature range creates a welcoming environment for bacterial growth, essentially letting microbes like E.coli and Salmonella throw a party of their own. In fact, according to the U.S. Department of Agriculture Food Safety and Inspection Service (USDA FSIS), the number of bacteria can double in just 20 minutes when food is held in the danger zone. Talk about a party foul.

Luckily, it's possible to minimize the risk of foodborne illness by holding food at safe temps. Ahead, learn how to keep hot food hot and cold food cold, according to food experts.

How to Keep Hot Food Hot

According to the USDA FSIS, hot foods should be kept at above the temperature danger zone, aka 140°F or higher. The easiest way to do this is to use chafing dishes. These are essential for safely serving hot food at cookouts. A chafing dish involves a large serving dish that's placed in a water pan, which is then set on a wire rack. A fuel can is positioned beneath the water pan to keep the dish hot. To use a chafing dish, "add about two to three inches of water to the water pan" about 30 minutes before serving food, says Kimberly Baker, director of the food systems and safety program team at Clemson University Extension Service. Cover the dish with aluminum foil and light the fuel can under the wire rack. When it's time to eat, "place the serving [dish] with food in the water pan so that the bottom of the food pan is resting just above the water," explains Baker. For best temperature control, make sure the food is heated to at least 140°F before you add it to the pan.

As the day (and night) goes on, use a digital instant read thermometer to check the food's temperature every one or two hours to make sure it's at 140°F or higher, suggests Green. While you're at it, regularly check the pan's water level, adding more water as necessary. Cover the food with a lid or aluminum foil to keep heat in, adds Baker.

You can also make a portable hot box using a cooler. "Wrap clean bricks with aluminum foil, [then place them] in an oven at 350 to 400°F until hot," says Baker. Next, line a large cooler with clean towels. Using hot pads or gloves, carefully lay the hot bricks along the bottom of the cooler, but on top of the towels. Place the hot food—which, again, should already be at 140°F or higher—on top of the bricks. Fold the towels around the food to provide insulation. During your cookout, keep the cooler closed as much as possible to maintain the right temperature, says Baker.

How to Keep Cold Food Cold

Cold food should be kept below the temperature danger zone, or at 40°F or lower. Compared to hot food, cold food is slightly easier to keep out of the zone. A cookout simply isn't complete without at least one cooler, so use one to keep your food cold. Fill your coolers with ice cubes or blocks, then add food that has been properly wrapped in plastic wrap or Ziploc bags, says Frank Proto, chef and director of culinary operations at the Institute of Culinary Education. "Always keep the cooler in the shade, [and] keep a thermometer in the cooler [to] monitor the temperature throughout the cookout," he adds. As with the cooler-turned-hotbox, try to keep your cooler closed as much as possible. Continuously opening and closing the cooler will let cool air escape, causing the temperature inside the cooler to rise, explains Green. If needed, have a separate cooler for food and/or drinks that will be accessed more often, suggests Baker.

Also, depending on the menu, consider having "one [cooler] for raw meats and another for ready-to-eat foods," says Green. This will help minimize cross-contamination, further preventing the risk of foodborne illnesses.

Another option is to serve food on top of ice. First, you'll need a serving container for each dish. Baker recommends using one with tall sides so you can set it deep into the ice, helping maintain the cold temperatures longer. You'll also need a bowl or pan that's larger than the food container. Fill the bowl or pan with ice, then nestle the serving container on top, she says. Check the food's temperature at least once an hour and keep it covered when it's not being served. And if the food is at 40°F for more than two hours? Toss it out, says Baker.

Other Tips for Serving Food Safely During a Cookout

Food safety doesn't stop at safe temperature zones. Follow these additional tips to prevent harmful bacteria from crashing your cookout. Start by cleaning your equipment. To avoid derailing your temperature monitoring efforts, keep your equipment clean. Wash your coolers and containers with hot, soapy water after every use.

You should also separate raw and cooked foods. "Watch out for cross contamination and separate raw and cooked foods," says Proto. This will prevent the juices of raw foods contaminating ready-to-eat dishes. Along the same lines, cook your food in batches. When you're ready to toss burgers or vegetables on the grill, cook in batches instead of heating everything at once. Smaller batches are likely to be eaten quickly and won't sit out for long, notes Proto.

And should you have any leftovers, be sure to refrigerate them quickly. If you know a dish is ready to retire for the night, bring it inside. No access to a refrigerator? Add plenty of ice to make sure it stays below 40°F.