Hi, I been using these bags for years for the wastebasket, but with my new KA Professional 6000 HD 6qt mixer instead of dropping a dish over the bowl with a towel over the dish/bowl, I decided to try using the 10 gal bag. I liked using it because I could see the progress of the dough, the dough never touches the bag. (I now keep one in the bowl when not in use, so I can reuse the bag many times.)
With the new mixer, I am now preparing 4 loaves of sandwich bread at a time, (freezing 3), when ready for final proof in the pans, due to the summer temps I can proof on the counter, so I have been putting 2 9x5 loaf pans inside of the bags tucking the edges in. What is cool is it traps air inside and the bags poof up so the rising dough never touches the bag, and I can see through the plastic as to how far they have raised.
Do the pros here think it's ok to use these bags for this? There is no smell associated with the bag that I can detect. The bread is only for home use.
I am not a chemist, so my word is not authoritative, but I have been doing this for years.
The concern would be plasticizers and volatile organic compounds (VOC) emitted by the bag. If it makes no contact with your dough then I think the only real issue could be VOC's. Most of those are released at higher concentration when the plastic is heated. I seriously doubt any of this has any real-world negative impact on your dough.