When it comes to food safety, I try very hard to follow the two-hour rule. If you don’t know what that is, “perishable food should never be left in the Danger Zone (41 to 135 degrees) for more than two hours.” This includes both hot food and cold food. If it’s been more than two hours, the food should be pitched.
Why? At the two-hour mark, there has been enough time for any bacteria in or on the food to have multiplied to a level that could make someone sick.