I'm leaving to go on vacation early in the morning and wanted to pack the car tonight. I'm making 2 cakes while we are gone and I was wondering if the fondant I made (MMF) and things like baking powder, PS, etc. would be ok in the trunk of the car overnight? I live in GA and the low tonight is only 77, plus I'm counting on at least 5 degrees radiant heat from the car. Will these things go rancid in that temp/ amt. of time?

I wouldn't trust it, but that's just me.
Right now it must be about 1,000 degrees humidity outside. That alone would stop me from putting food in the car overnight.

I think the powdered sugar and dry ingredients would be fine. I wouldn't pack the MMF or anything like that yet though.

It'll be fine in the sense that it's not going to go rancid, or anything, but sometimes textures change when something is exposed to warmth in a closed container. Sometimes, those changes can effect the product when you go to use it.

Personally, I'd keep it in the house and travel with it in the body of the car, NOT the trunk.

JMHO
Rae

Thanks everybody. I was sort of thinking so, but I was hoping it would be alright since it would be one less thing to do in the morning.