How long can American cheese slices go unrefrigerated?

Here's why:

* Bacteria growth: Unrefrigerated cheese is a breeding ground for bacteria, especially in warm temperatures. This can lead to foodborne illness.

* Spoilage: The fat and moisture in cheese can go rancid and develop an off-flavor and odor when left out for too long.

* Safety guidelines: The USDA recommends keeping all perishable foods, including cheese, refrigerated at 40°F (4°C) or below.

Exceptions:

* Processed cheese spreads: Some processed cheese spreads, like those in tubs or jars, may have a slightly longer shelf life at room temperature due to their low moisture content and added preservatives. However, it's always best to check the product label for specific guidelines.

Always err on the side of caution and refrigerate your American cheese slices as soon as possible.