Newswise — When it comes to back-to-school safety, you cover the basics vigilantly, such as teaching kids to avoid strangers, buckling them in the car and providing appropriate safety gear when they play sports. But have you considered taking as much care when it comes to packing lunch boxes? An improperly packed school lunch can lead to spoiled food and a missed meal at best or food-borne illness at worst.

“When you’re packing a school lunch, it’s important to think about the perishability of the foods you’re making,” says Rutgers University professor Don Schaffner, an extension specialist in food science and spokesperson of the Institute of Food Technologists (IFT). “Perishable foods can remain at room temperature for no more than two hours – one in the summer due to the heat. Properly refrigerated foods can last a long time, but most school children won’t have access to a refrigerator where they can store their lunchbox.”

The Institute of Food Technologists, a nonprofit scientific organization focused on the science of food offers some guidance for parents as they pack lunches this school year:

* Start each day with a clean box or bag. Insulated, vinyl lunch bags are popular, and do better at keeping foods cool than paper bags or metal lunch boxes. When kids come home, clean out lunch bags using warm soapy water, and allow it to dry completely overnight before packing the next day. This helps deter the growth of bacteria in the bag.

* Choose secure packing materials, such as sealable, single-use sandwich bags that can be disposed of when used, or reusable plastic wear that is dish-washer safe. Always use clean packing materials.

* As much as possible, opt for foods that are not perishable, such as peanut butter and jelly sandwiches. “It’s a kid favorite and neither ingredient is quickly perishable,” Schaffner points out. “You don’t have to worry about refrigerating it, and it will last from the time you prepare it in the morning until kids consume it at lunchtime.” Single-serve fruits in pre-packaged containers, such as apple sauce or fruit cocktail, are also great options because they’re less perishable.

* Encourage older kids to assemble lunch on their own at school. Pack bread in one container and place fillings like meat or cheese separately with a cold pack. Having kids assemble the sandwich themselves ensures the freshest possible results – and no soggy bread!

* Cold packs are designed to keep food cold, not cool it down. If you make the sandwich in the morning with room-temperature ingredients, it’s unlikely the cold pack will be able to cool the food sufficiently. Instead, make the sandwich the night before and refrigerate the whole thing, or use refrigerated ingredients to ensure the sandwich starts out – and stays – cool.

* Always use a cold pack when you are packing anything perishable, like a sandwich with meat or fresh cut fruit with a yogurt-based dip. Place the perishable food right against the cold pack in the bag. Wash the cold pack in warm soapy water after every use before returning it to the freezer.

* For hot foods like chili, soup or stew, use an insulated container. Before storing the food, fill the container with boiling water, let it stand for a few minutes, empty it and then add the hot food. Keep the container closed tightly until lunchtime to help minimize the risk of bacterial contamination and growth.

Finally, says Schaffner, think ahead.

“Not planning adequately, not thinking about the amount of time it’s going to take, from the time that food is prepared until that food is eaten, is a common mistake,” he says. “At night, wash the cold pack and make sure it goes back in the freezer so it’s ready for the next day. Give yourself plenty of time in the morning to wash your hands thoroughly before handling food. And keep stressing to kids the importance of washing their own hands before they sit down to lunch each day.”