How does food in a supermarket freezer stay frozen?

Food in a supermarket freezer stays frozen through a combination of low temperatures and efficient insulation. Freezers are maintained at temperatures typically below 0°F (-18°C), which prevents the growth of bacteria and preserves the food's quality. Additionally, the freezer's insulated walls minimize heat exchange with the outside environment, ensuring that the cold air remains contained. Regular monitoring and replenishing of the freezer's cold air also help maintain consistent temperatures.