How do you know if cookie dough has gone bad?

* Smell: If the cookie dough has a sour, rancid, or anything other than a sweet aroma, it's likely gone bad.

* Texture: Good cookie dough should be smooth and pliable, but if it's crumbly, or feels wet and sticky, it may have spoiled.

* Color: Fresh cookie dough is typically a light brown color, but if it has darkened significantly or has spots of mold, it's time to toss it.

* Taste: If you're unsure about the dough's freshness, take a small taste. If it tastes bitter, sour, or off in any way, it's best to discard it.