Originally Posted by HauserHooch
190 isnt going to be enough to melt them.
For what it's worth, pasteurising in standard PET bottles is not recommended.
From the point of of view of safety, there are some plastic bottles that will leech the chemicals in to the product when they are subjected to heat. From the point of view of just usability while heat may not melt them they may become slightly maleable. Combined with the pressure of the carbonation and you could find that the bottles bulge, or most likely that the bottom of the bottle pops out which is kind of interesting!
Bottles designed for pasteurisation in plastic are called 'hot fill', and they're what the fresh juices are bottled in to as the juice is heated to 85-90 centigrade and bottled at that temperature to pasteurise. Here in the UK they're impossible to buy for a small guy, but in the States where they're manufactured you may have more luck.
Lastly, unless you're buying very specific niche plastic with a special oxygen barrier layer inbuilt in to the bottle then believe it or not the plastic is actually porous. If you look at a bottle of coke etc you'll find that it actually has a pretty short shelf-life of only a few months. That's not because it'll go off (the contents are almost all man-made) but because the fizz will disappear pretty quickly! If you're bottling something that's oxygen sensitive like beer etc then the reverse is true that ultimately it will allow some air in.
Now, this is all the theory. I have very little experience in bottling in to plastic, but I thought I'd share. It's entirely possible that all will be OK, but at least if you know what the potential pitfalls are then you know what to look out for.