Guys, it's a very simple idea. We know that it's possible for plastics to leech materials into liquid they come in contact with. The degree to which this occurs is open to speculation and experimentation. The effect on your beer, and on you after you drink it, is open to the same.
If a given material is rated food grade to a certain temperature, and you are using it above that temperature, it is no longer food grade. Refer to the first paragraph. If you want to trust it, go nuts. Don't smack other people about for finding, or even claiming, that it's causing problems, though. You can't be certain yourself unless you've applied the same tests the manufacturer would have to in order to label it food grade. Why would they only label it food grade to 65? Maybe it's a business decision to sell the same hose at two different ratings with a premium on the higher one. Maybe it's because the hose failed the food grade tests at temperatures above 65. Whatever the reasons, it's not food grade unless it's been demonstrated to be so by an approved testing house under the applicable standards. You're welcome to your opinion on whether that's a problem, and you're more than welcome to use it in your brewery anyway. It probably won't kill you. It probably won't harm you. It might not even introduce bad flavours to your beer. But don't smack the guy who thinks it might, finds anecdotal evidence - however unscientific his method may be - to support the theory, and decides to use hose that israted to the job, then recommends such practice to others.
If you want to be certain that the materials you use in your brewery are safe for contact with hot wort for human consumption, then use materials that are rated food grade at greater than boiling temperatures. Generally, that means stainless steel and silicone. I'm not going to start the galvanic corrosion argument again here, but it applies as much as my above arguments. You might have been using it for years and never noticed any ill effects. But let's face it, you were drinking at the time, and you didn't happen to have a chemical testing facility in your trousers.
h34r:
