Boiling plastic tubing...

[AfternoonReview]

I had crud built up in my blow off tube so I decided to boil it in my brand new 20 qt ss pot.

I leave it boiling for 5 or 10 min and when I get back to it, the tube had gone from clear plastic to opaque white. Now I'm worried that I leached dangerous plastic chemicals into my steel pot, and I'm also concerned about the safety of using the tube again. I don't mind getting more tubing, but I don't want to think I just ruined a brand new pot.

Anybody know about stuff like this?

I searched the forums and only found a few somewhat related threads...

dang it
and
thanks

 

[Schnitzengiggle]

You're probably all right, but if you want peace of mind, scrub your pot well with some Bar Keeper's Friend (BKF).

I use the stuff about every 4-5 brews or so to get the mineral build up off the bottom of the inside of my pot, and when I first used my pot on my burner, all the paint (even though I cooked as much of it off, before using it) laquered the bottom of the outside of the pot. Some elbow grease and BKF solved that problem too!

BKF will also passivate the SS, so if you use it, let you pot air dry then make sure to polish your pot with a dry towl, to remove the oxidation. The stuff is truly awesome for SS.

FWIW, I give the outside of my corny kegs a really good scrubbing with the stuff when I get a new one, it is remarkable how much better they look afterwards.

 

[AfternoonReview]

Thanks for the quick reply. I'm pretty paranoid about stuff like this. I don't want to ingest any carcinogens if at all possible!!!
When you say that BKF will passivate the SS, what do you mean by "passivate"?
And, is it possible at all for stainless steel to absorb chemicals that could leach off of plastics? I'm not familiar with the science behind all of that.

Thanks again

 

[Schnitzengiggle]

Thanks for the quick reply. I'm pretty paranoid about stuff like this. I don't want to ingest any carcinogens if at all possible!!!
When you say that BKF will passivate the SS, what do you mean by "passivate"?
And, is it possible at all for stainless steel to absorb chemicals that could leach off of plastics? I'm not familiar with the science behind all of that.

Thanks again

I'm not too familiar with all the science either...however, "passivation is the spontaneous formation of a hard non-reactive surface film that inhibits further corrosion. This layer is usually an oxide or nitride that is a few nanometers thick" (wikipedia).

Stainless still can still rust, for example, one of my corny kegs has a decent scratch on it where it was more than likely dropped or dragged across the ground at one time in the past by some careless soda delivery bastard...bastards!

Anyhow, that scratch had rust in it, of course the corny keg is stainless steel, so how was it rusting? It was because the passive layer was removed where it was scratched, and it had never been repassivated at that site. I took some BKF, scrubbed the feric oxide off with BKF, and allowed it to dry, then polished it with a dry towel, no rust since, not even when it has formed condensation from the temperature change when the kegerator door has been opened for a keg swap, or when it was empty and removed.

If you are interested in learning about the passivation process specifically when it applies to stainless steel, google stainless steel passivation, you'll find a ton of info on it.

Long story short, it is a chemical layer that protects the steel. BKF strips the steel, and as it dries the passive layer is replaced when exposed to oxygen...I think that is how it works, I'm sure some Chemical engineer, or Metalurgist will chime in and correct any mistakes in my explanation, but I think that is the gist of it.

 

[theredben]

And, is it possible at all for stainless steel to absorb chemicals that could leach off of plastics? I'm not familiar with the science behind all of that.

Thanks again

Not in any real sense, maybe a few molecules are still stuck to the surface, but you and I will not find them.

 

[AfternoonReview]

Thanks again! I went out and got some BKF and cleaned it up real nice last night before I made my batch. From what I gathered on the internet, stainless steel doesn't generally absorb contaminants. As far as the tube is concerned, I'm using it for blow off right now, but I'll probably get a new one before I need to siphon any beer out.

 

[Sawdustguy]

If you are going to boil your tubing in the future make sure it is silicone tubing. You never know what sort of chemicals can leech from plastic tubing at boiling temperatures.

 

[AfternoonReview]

I hear ya. I'll definitely look into it. Thanks!

 

[AfternoonReview]

What the?

I went to check on my fermenting beer, and the blow off tube is clear again!?!?!?!?!

So weird.

 

[AfternoonReview]

I emailed Brooklyn Brew Shop about what happened and they sent me a new tube for free! Problem solved.

I think I will get silicone in the future though.