ok so sill me bought some carrots a few day ago and left them in the bag.
There are some patches of mold on them and I am wondering if it is safe to cut off /peel the moldy parts and still use them. Any experience?
When it comes to veggies and fruits, if you can cut the mold off I think you're fine. I'd probably salvage what I could and freeze them to use in making stock.
I wouldn't. Mold has roots, and while they don't penetrate as deeply or spread as widely in hard items like carrots as they do in, say, cheese... still, if I see mold the item (and all surrounding items) are trash. No exceptions.
And I am one who would have zero issue eating yogurt and cheese that had been left out overnight.
But mold is different.
It depends on how big the moldy parts are. If there are only small mold patches, I would (and have) cut off the moldy parts plus a bit extra, wash the "mold free" carrots and store them in a fresh bag, NOT the one that may have mold on the inside. I'd also use those carrots for cooking, not for eating raw.