So I'm winterizing my RV a while back, and the potable water antifreeze label reads 99% propylene Glycol, 1% water and dye. It is list by the USDA as GRAS (Generally Regarded As Safe). Since it goes into the drinking water supply of the RV, I am wondering if it would be the same as the PG used in juice? The only difference that I can see is the dye which makes it pink colored so that you can see it in you lines and know that they are filled and protected from freezing. If it is the same, it sure is a lot cheaper than what is available on line. At Lowes, it ran about $4.50 per gal. I had to use 3 and a half gallons, so have a considerable amount left. What do you think?