Final answer:
When displaying food in ice, it must be 41°F or colder to ensure safety and to prevent bacterial growth. Food should not sit on top of the ice or be at room temperature, as these conditions do not maintain a safe temperature.
Step-by-step explanation:
When displaying food in ice, it is crucial to ensure that the food is maintained at a safe temperature to prevent bacterial growth. Based on the temperature guidelines provided, the food must be 41°F or colder. This ensures the food remains in a safe zone which inhibits bacterial growth that can happen in warmer temperatures. Foods preserved on ice should not sit on top of the ice as they may not stay adequately cold; they shouldn't be room temperature because they can enter the danger zone for microbe activity quickly; and they need to be colder than 45°F to stay within safe consumption ranges.
It is important to remember that perishable foods left at a temperature between 40°F and 140°F for more than two hours should be discarded. Therefore, ensuring that food temperature is kept adequately cold while displayed on ice is critical for food safety.