Nylon (and other plastics) leaching off flavours into wort

[mattd2]

HI all, just want to get some other peoples experience with using nylon in contact with boiling wort. Background is I now have a flowmeter hooked up to my pump, the housing is made from nylon. So far what I am reading is nylon should be physically able to handle 100°C / 212°F wort but not 100% sure on if any flavours will come out. I have seen people using "nylon" mesh bags for hops / grains but I have never been 100% sure these are nylon or some other plastic.
So anyone want to ease my concerns with their experience?

For the record I am planning on testing it by pumping boiling water round for 1-2 hours and then checking to see if I can taste anything.

Cheers

 

[wilserbrewer]

I don't think the nylon will change the flavor at all, it is my understanding that it is inert well beyond boiling temps.

Your experiment could change the flavors slightly for other reasons so be careful how you interpret, the placebo effect is possible as well.

 

[Hello]

I've done a small batch BIAB with a large nylon hop bag and I do not detect off flavors. If there are off flavors in my batch of beer I would suspect that I would not immediately think it was the nylon.

As nylon hop bags are often described as bags to be used when adding hops during boiling and dry hopping, I suspect there is little to no data on them causing off flavors. If you are in serious doubt then do not use it.

 

[mpcluever]

What flowmeter are you using?

 

[mattd2]

Thanks guys! Not really in serious doubt but would hate to have to dump 5 gallons of what could have been good beer. Sounds alright though
If I do pick up anything in the test Wilson, I'll remove the flowmeter and redo the etat to check it was actually the meter and not something else.
mp - it is just a cheap paddle wheel type, was only about $6 or so. Some people have said that they can get stuck with grain particles, another thing for me to look out for!

 

[rico567]

I have used the following plastics in every batch of beer I've made:

1. Plastic in Rubbermaid "Big Orange" cooler for mashing.

2. Plastic in paddle I use to stir the mash.

3. Vinyl tubing used for siphoning, bottling.

4. Plastic (HDPE) used in fermentation bucket.

5. Plastic liners in bottle caps.

6. A big pitcher (looks like nylon, but ???) that I use to vorlauf.

7. Plastic in Better Bottles I (rarely) use to do a secondary.

So far, no off-flavors to report. My beer is fine. The plastics listed here are such standard parts of many homebrewing rigs that I can't help but think that some sort of systematic reports would have come in by now if anything was in fact getting into the beer.

 

[mattd2]

Thanks guys! Not really in serious doubt but would hate to have to dump 5 gallons of what could have been good beer. Sounds alright though
If I do pick up anything in the test Wilson, I'll remove the flowmeter and redo the etat to check it was actually the meter and not something else.
mp - it is just a cheap paddle wheel type, was only about $6 or so. Some people have said that they can get stuck with grain particles, another thing for me to look out for!

So I tested it the other day - about 75 mins of constant pumping at just under bioling temp (the pot was boiling). There was some "flavour" but as Wilson said I don't think I would be confindant saying it was 100% definately the flowmeter. I also tried to get the flow meter to "stick" and ended up having to have bout a handful of whole grains being pumped through to cause any problem.
Ended up brewing a beer with it the other night, 7.5% Strong Scottish Ale. We'll see what that ends up like in a couple of weeks!