Homemade Frosting - Walkerville,MI

Refrigerate!!!! Refrigerate!! Refrigerate!!!!

I'd keep it in the fridge

I do cake decorating. I prefer to refrigerate everything. It just makes me feel better and safer about things. Generally the rule of thumb is a 6 hour limit (or 3 days for butte cream made without milk) out of the fridge. Dairy products nowadays are pasteurized, so that slows down bacteria growth. And believe it or not,the sugar drastically slows down the rate of spoilage too. So although it will probably be ok being left out (especially if the sour cream was heated either by melted chocolate or cooking), it's better to be safe than sorry and stick it in the fridge.

fridge, with it having sour cream in it I would definitely keep cold even after the cake is frosted

Throw it in the frig mostly because of humidity. Once you frost whatever you're frosting it'll be fine in or out of the frig.

I'd keep it refrigerated.

I think I'd always err on the side of safety...don't want to make anyone sick. You can always set it out to come up to room temperature before spreading.