My dog used to do the same thing. he once ate poo. I don't see any point of punishing Tess as she was exploring, tasting a lot of things. Who hasn't anyways had the thought of touching human poop? (Gross!) My dog ate poo once and then he never ever ate again. Just when you see her eating poop tell her a big loud NO! And stay away from her. This will get Tess to socialize that eating poo means punishment and you staying away from her. Don't worry, it's a dogs nature.