Food is a big part of summer camping, picnics and cook outs.
Plan the right amount of food to take and you will not have to worry about storage or safety of leftovers. Pack coolers right from the refrigerator. Put food in an insulated cooler or ice chest and cover with ice or commercial ice packets. Place the cooler in the shade and don't constantly open it. Keep drinks in a separate cooler instead of mixing with more perishable items, and that will slow frequent opening and closing the lid.