When using ice to keep foods cold the food container must be surrounded by ice to the level of the food which is the best way to tell if the food is staying cold enough?
Food must be colder than 41 ° F when you put it in the ice. Hold cold foods at 41 ° F or less. Cold food is held at 41 ° F or lower to keep germs from growing. It should be measured for temperature using a probe thermometer at least every four hours.