You can go online to Lunchboxes and purchase many lunch boxes of different materials and sizes. Alternatively, you can go online to PlanetBox to buy a better version of the standard metal lunch box.
To keep the food cold and from developing bacteria.
put them in cold water
To Keep food cold so it doesn't spoil. Also to keep things that are supposed to be cold cold. Also to keep foods that are supposed to be frozen frozen.
You generally place the containers of food on a bed of ice.
Keep hot foods hot, and keep cold foods cold.
To keep cold food cold or hot food hot. Styrofoam is very good insulation.
to keep food cold
To keep food from spoiling and keep it cold.
Because it keeps food cold.
To keep cold food cold or hot food hot. Styrofoam is very good insulation.
To keep food cold that needs to be kept cold.
Cave men likely burned wood, animal dung, and dried plant materials to cook food and keep warm. They would have used simple fires made from these materials to generate heat for cooking and to stay warm in their dwellings during cold weather.