What indicates that food has been held at unsafe temperatures?

Using a temperature measurement is the most reliable method for determining whether food has been held at unsafe temperatures. Temperature is a critical factor in food safety; food must be maintained within specific temperature ranges to prevent the growth of harmful pathogens. The USDA and other food safety guidelines typically indicate that food should be kept at temperatures below 41°F (5°C) for cold foods and above 135°F (57°C) for hot foods.

By measuring the food's temperature with a thermometer, food handlers can accurately assess whether the food has been kept at temperatures that are safe for consumption. If the temperature falls outside of the recommended range, it indicates that the food has been held at unsafe temperatures, putting it at risk for spoilage and foodborne illness.

In contrast, inspecting the color of the food, finding a strange smell, or feeling the chill of the food can provide some clues about food safety but are not definitive measurements. Color changes and odors may indicate spoilage but are not always reliable indicators, as some foods can be spoiled without noticeable changes. Similarly, merely feeling if food is cold does not provide an accurate assessment of its temperature, which is necessary to ensure safety.