Beer line tests & solution to the "plastic" taste

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kal

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Hi!

Note: This info was in multiple posts in Forced to use 1/4" (not 3/16") for 15' beer line? thread but it's lost in there so I'm reposting here for easy reference as the subject seems to come up a lot.

My setup:

4 taps with 12-15 feet of beer line on each to a freezer set to 40F. 5-6 feet of line is outside the freezer. Shanks and beer line are chilled to 40F using a cooper loop circulating a coolant fluid. More info & pictures here and here.

Definitions:

Poly vinyl chloride (PVC), or 'vinyl hose' - Flexible, easy to work with, wall is usually very thick when using for beer:
547C.jpg


Polyethylene, or 'poly tubing' - Hard and unflexible, wall is usually much thinner than vinyl:
548BT6000.jpg


Problem:

All vinyl line seems to cause some 'plastic' taint if the beer sits in it long enough. In my setup when vinyl line is used the first 2-3 oz has a plastic taste if I go more than 3-4 hours between pours. Happens with light lagers to heavy IPA's. All lines and taps have been cleaned, sanitized, etc.

Makes no difference if the line is 'food grade' or not. Food grade does not mean that it won't impart a flavour to the substance passing through it, it just means that it meets certain FDA standards. None of the NSF standards guarantee either that a taint won't occur. The two that are the most brought up in reference to beverage use are:

NSF 61: Certification applies to materials for use in the conditioning, filtration and transport of drinking water.
NSF 51: Certification applies to materials used in the production or delivery of food and beverage products.

More information: www.NSF.org

Speaking to the engineers who manufacture industrial beverage line at Kuritec/Kuriyama and Arrowhose, it seems that the only way to get rid of this taint is to use what's called 'barrier tubing'. Barrier tubing is poly tubing with a glass-like barrier in it made out of PET (Polyethylene terephthalate) material, the same stuff that plastic pop bottles are made from. Barrier tubing is usually used for setups where the lines aren't 100% dedicated to a certain beverage. You can actually go from pop -> milk -> cranberry juice without any cross-taints as long as you flush the lines properly in-between.

Tests:

I tested multiple types of vinyl hose and poly tubing. Testing was done by leaving water in each hose/tubing (not connected to anything) for 24-48 hours. The water was then tasted and compared to regular tap water.

Vinyl hose:

(1) Defective morebeer.com 3/16" generic clear vinyl hose: This line was the reason I started on this quest. As it turns out, I had received a defective batch of their 3/16" vinyl hose that wasn't made to spec and caused more of a plastic taste than usual. Horrible plastic taste, even after beer or water has sat in it for only 2 hours. There's no way anyone would find this acceptable. The hose in unmarked so I do not know who's hose they use (morebeer.com would not make it themselves of course). Instead of getting it replaced they simply refunded me so I could not compare it to non-defective hose.

(2) Arrowhose.com 3/16" type 14 clear vinyl hose: Some taint. Less than (1) which is expected as (1) is defective. (2) is probably what most people use or are used to. This hose type is used and sold at many places. NSF-51 and FDA (food grade) compliant. A local draft installer in town has done 700 installs with this stuff.

(3) Arrowhose.com 3/16" type 14 clear vinyl hose: Second sample of the same hose as (2), bought at a different location, different batch. Still some taint just like (2) above. I wanted to try a second piece just to be sure.

(4) Generic clear vinyl hose from Home Depot: Worse than (2).

(5) Simgo.com generic 3/16" clear vinyl hose: Same taint as (2).

(6)Kuritek Bevlex Series 200 Clear vinyl hose: Same taint as (2) more or less. May be just slightly less. This is the best vinyl hose according to the Kuritek engineer I talked to. He uses it in his own own home bar.


Poly tubing:

(7) Arrowhose.com 1/4" type 58 poly tubing with "flo-guard" barrier: Very subtle plastic taint. Much less than all above. This tubing uses a PET inner lining. NSF-51, NSF-61, FDA food grade. Not available in 3/16" size. Here's an online brochure about their "flo-guard" type tubing.

(8) Arrowhose "type 5C" grey poly tubing: Very subtle taint. Less than (7), much less than any of the vinyl hose. This is an odd tubing, one that I basically purchased by accident: One supplier told me that he could get 3/16" Arrow type 58 but I was sent this stuff instead. It's a custom order type tubing made once in 2001 without any barrier at all. I only include it here for reference purposes.

(9) Generic Home Depot 3/16" white poly tubing: Very suble taint. Less than (7), much less than any of the vinyl hose. Very similar to (8). This is similar to what most people would use to do a water line for a fridge with water in the door and/or a built-in ice maker.

(10) Kuritek.com 1/4" Bev-seal Ultra Series 235 poly tubing with barrier: NO plastic taint at all! This tubing uses a PET inner lining. 2013 UPDATE: While Bev-seal Ultra series 235 was not available in 3/16" sizing at the time I wrote this, it appears to be available now.


Conclusions / Comments

1. Most vinyl line is not that bad, most people will either not care or simply pour off the first 2 oz or so as it likely won't be cold anyway unless your entire system is chilled.

2. Poly tubing is better than vinyl in all cases.

3. Number (10) (Kuritek.com 1/4" Bev-seal Ultra Series 235 poly tubing with barrier) is by far the best and the only one that didn't leave any taint at all, even after extended periods. It's what I use now. Beer can sit in the line for 2 weeks and the first 4 ounces that sat in the line tastes the same as beer from the keg.

Not everyone can use 1/4" line and still have a balanced system due to the lengths required at the regular pressure of around 12 PSI as 1/4" has considerably less restriction than 3/16" line. To make matters worse, the glass-like PET coating on barrier poly tubing reduces restriction even further. I however like my draft beer served like in the pubs: A bit less carb'ed than bottled beer. I keep my Ales at around 3-6PSI and pump through about 8'-10' of the 1/4" poly tubing, and my lagers and wheat beers at around 5-8PSI and push through 12-15' of 1/4" poly tubing. This works great for me with 1/4" poly line and keeps the whole system balanced. (No need to adjust the regulators, ever).

I bought the Kuritek.com 1/4" Bev-seal Ultra Series 235 poly tubing from Simgo.com in Mississauga Ontario Canada for $0.21/foot CDN (US/CDN exchange rate is more or less on par). No idea if they ship to the US. Simgo.com is reseller distributor but they do also sell to enthusiasts directly if you ask. You have to call, there's no ordering online. In Canada shipping is dirt cheap even for large orders (I've never paid more than $7 for a large box) and it always arrives the next day via courier for me as I'm in the same province. Their prices are typically 1/2 of what you'd pay at resellers of beer equipment. If they won't sell to the US, call up Kuritek and find out who their distributors are and then bug them for places that sell their Bev-Seal tubing.

4. A word of warning when using poly tubing. The stuff's a lot stiffer than vinyl so it's harder to work with and leaks are easy to create. You need to make sure that the barbed ends you work with are good and sharp so that you can get a good fit and USE HOSE CLAMPS! 1/4" poly fits directly on to 1/4" barbed disconnects and shank nipples. Poly doesn't have the same stretch as 3/16" vinyl, but you can make 3/16" poly fit over a 1/4" barb if you hold it in boiling water first for 30 seconds and then push it on very carefully to not crink it.

5. Some people have told me that this 'taint' is all in my head and that they use the same type of vinyl that I've tested and do not notice any off-tastes. It could be that the amount of taint that vinyl line produces is reduced over time. I did not however notice any difference over the 3-4 months that I used the (2) vinyl hose. As for it being in my head, I had a few other people (brewers and non-brewers) taste water samples without telling them which hose they came from, nor did I mention what the off-taste tasted like. I had them rate them and most people rated the order the same as me, and noticed what they called a 'plastic' or 'rubber band' or 'rubber boot' taste. If you don't notice it yourself, good for you! Enough others have posted recent threads on the subject that I don't think I'm alone.
 
Glad you carried this information forward from your other thread. Good information... I definitely get a little plastic taste in my first 2oz. poured after letting a tap un-tapped for a few days. I don't plan to change to the 1/4 tube at this point as I don't mind pouring out 2oz. each time I plan to tap it, but some this may help a lot of people out!

Prost-ed!
 
Yes, most people won't bother and won't be bothered by it. I figured it would be good for people to know the issue up front so that they can either look at alternatives or just says "it's not worth the hassle" and go vinyl anyway. I always hate surprises myself!

Kal
 
Are your lines at a warmer temp? Do you think this affects it more or less? If you have all of your lines up to the tap at serving temp I wonder if you would notice the flavor as much..just a thought.

J
 
I have 8' of line on each keg, only the last 6" are not refrigerated (the lines in the tower)... Not sure if this effects it or not. Could contribute I suppose. Either way I'm please with my beer after tapping off the first 3oz. I keep two sampling cups from brewfests on top with my pint glasses, goblets, etc. and just fill one each time before we start to drink from a tap. Works fine...

Either way, I reiterate, kal has done a lot of research and posted some great info here!
 
I can taste the "off flavor" if I pull a taster but if I pour an entire pint, the taste is so well diluted with fresh beer that I don't mind it. I just hate it when someone wants to try one of them that hasn't been poured in a while. I have to dump the first 2oz because I'll be damned if that's what they think my beer tastes like.
 
Bobby_M said:
I can taste the "off flavor" if I pull a taster but if I pour an entire pint, the taste is so well diluted with fresh beer that I don't mind it.
This is one reason why I like the barrier tubing solution: Everyone always wants to try all 4 taps that I have on the go. I'll often want to try myself as well just to see how a beer is aging. I hate always pouring off 2-3 oz and then only taking 2-3 oz to taste. :)

Kal
 
I've been looking into this and Kal's information and research has been very helpful. Since I plan to do beer and soda I may end up using the Home Depot Poly for the soda so I can have very little taint as well as lines that are not 50' long (Soda is usually kept at 30 PSI I read). I then may still get some Bev-Seal 1/4" for beer, but not positive yet where I can get it in the US
 
I found Poly tubing at Farm and Fleet for .17 cents each. It's a local store so no shipping. I bought some .170 ID tubing (.07 cents each) and that is just too darn small to get over any of the 1/4" fittings. So I'll have to go back and pick up the actual 3/16 (.185) tubing from there to give it a try. This would be a cheap and almost plastic-taste free way to work my system.
 
mr x said:
I do use some ss for my 3 gallon keg I haul around,

Interesting. I'm new to kegging and I'm just starting to get my set up together. I have a chest freezer now and I've got four 5gal cornies on the way but I've get to pick up anything else. I'm wondering if SS lines would make sense. I know that they would be harder to route and that they wouldn't offer up much in the way of flexibility in the long run in terms of changing the set up, but I'm wondering what your experience has been like using SS.

Off flavors? Maintaining them? Others?
 
I use plastic in my kegerator at the moment, and it works well for me at the moment, so I haven't had much cause to change it out. I use ss for my portable setup wrapped around the corny in a small igloo cooler for heat transfer purposes only. But there is no off flavour issue, and maintenance is just BLC if necessary.
 
I just purchased some generic home-center 3/16 vinyl tubing for my soon-to be running kegging operation.

I am glad I ran across this, because I am a bit sensitive to plastic aromas, and also a bit concerned about the chemical ingestion (if it smells and tastes bad, is it good to ingest??)

Anyway, I did a bit of searching, and came across Tygon tubing, sold a US plastics, and other places. Has anyone used it? It is available in 3/16 ID, and promises to be taste- and odor-free.
 
From speaking to the engineers who make this stuff, one thing they all said was: If you truly don't want any flavour leeching you need to use 'barrier tubing'. Nothing else will give you that level of flavour isolation.

Barrier tubing is lined with PET material.

Kal
 
Better Bottle has the PET barrier Bev-Seal tubing on there website. They show a handful of distributors in the US and a ton in Canada.

They also show a bucnh of vendors (HBS) that carry there products.

I've been meaning to replace the majority of my tubing and this seems like a good idea
 
I really wish I could find 3/16" bev-seal tubing, but they don't make it.

Nope. Only 1/4" ID and bigger. Which is why I didn't consider it for the longest time. I was told that you should always carbéserve at around 12PSI and that as it turns out is WAAAY to carbonated for me. So I went 1/4" ID on my 12 foot hoses and my PSI is set to only 4-5 PSI and the beer is PERFECT.

Kal
 
I had a similar issue with the normal beer line that was sold in my LHBS. For the first keg, it was very noticable especially in the first few ounces of the pour. If I discarded whatever was in the beer line, the taste was quite a bit less noticable. After running the same lines for a couple weeks this flavor disappeared, and since then I haven't tasted it. I've put maybe 4-5 kegs through since I build my kegerator and except for that first one, I've had no problems. Maybe it's just a manufacturing thing, or there is some sort of residual on the lines that doesn't easily clean off. I still don't know why I got that flavor, but it's gone now and I'm happy :D!
 
Not sure why some people have issues and some don't. Maybe super sensitive taste buds. I use that cheap-a$$ Home Depot beverage tubing and have for months. Never noticed a plastic taste in any beer.
 
This is what I've got. Its what the LHBS gave me when I asked for beer line. I'm not sure what the difference is though.
 
Not sure why some people have issues and some don't. Maybe super sensitive taste buds. I use that cheap-a$$ Home Depot beverage tubing and have for months. Never noticed a plastic taste in any beer.

Let it sit unpoured for more than an hour for a change! :ban:

No, seriously, after letting it sit overnight, pour only a 2oz taster, then pour off another few ounces into a pint glass, then pour another 2oz taster. Do an A/B blind taste test. The last 2oz pour will taste much better than the first.
 
Interesting, maybe I'll have to try that. I always pour out 1-2 oz every time I pull the tap, so that might be why I don't see much of an issue.

Let it sit unpoured for more than an hour for a change! :ban:

No, seriously, after letting it sit overnight, pour only a 2oz taster, then pour off another few ounces into a pint glass, then pour another 2oz taster. Do an A/B blind taste test. The last 2oz pour will taste much better than the first.
 
If not because of the off flavor, why do you pour off the first 1-2 ounces? Temp? Jus curious. Putting final (for now) touches on keezer and putting a keg of apfelwein in tomorrow for New Years. I've drank two kegs (mild and Scottish 60) from it but with just a collar and picnick tap. NowI have the tap box all set I'll post pics after the holidays in the kegerator forum. Been waiting a long time to do that!!
 
Hmm. Glad I came across this thread, as I recently (2-3 weeks ago) got a shipment of some 3/16" tubing from morebeer and replaced the line on two of my three taps and I can definately taste a plastic flavour in the first few ounces. Even worse is that on my lightly hopped lager the chemical smell is really overpowering. It has no name or label on it and I am now wondering if they really got a "bad batch" or if all of the stuff is bad. Does anyone else use the morebeer 3/16 line and have taste/smell issues?

The unchanged tap has the arrow brand of tubing and I can not notice any off flavours from it and I have even tried swapping the kegs around. I can without a doubt say that the morebeer tubing I just bought is giving severe off flavours and smells to my beer compared to my existing line (arrow brand)
 
Well I am getting off flavors from my keg of apfelwein if I don't pour off the first few ounces. I never noticed it in the 2 kegs of beer I went through before adding the tap box (picnick taps that stayed inside the fridge) I'm wondering if it is just from the line heating up inside the box. I'm on my way out to the garage to start messing with a PC fan I found laying around. Going to push air from the bottom of the fridge up to the box around the lines. Hopefully this fixes everything. Once cold, the apfelwein tastes fine.
 
Update: I e-mailed morebeer a couple nights ago and let them know I was getting some severe chemical smells and tastes from my beer line that I just got from them and this is what they had to say "I am very sorry for the inconvenience. We did get a recent run of tubing that was defective. We have been assured by the supplier that the tubing is not dangerous, it's just causing whatever goes through it to taste bad. " I am currently in the process of tracking down a supplier for the line I am using on the rest of my taps. It's made by ARROW hose and its TYPE 14 PVC with NSF-51 stamped right on it. The morebeer stuff doesn't have anything written on the tubing. I will report back with my findings.
 
Update: I e-mailed morebeer a couple nights ago and let them know I was getting some severe chemical smells and tastes from my beer line that I just got from them and this is what they had to say "I am very sorry for the inconvenience. We did get a recent run of tubing that was defective. We have been assured by the supplier that the tubing is not dangerous, it's just causing whatever goes through it to taste bad. "

I started this thread so see my first post for my Arrow vs B3 no-marking tubing findings.

They email they sent you is word for word the same email they sent me when I complained about their tubing a year and a half ago. Right down to the "we have been assured by the supplier that the tubing is not dangerous".

I'm tempted to call bull-sh** on this.

I'm starting to think that they just have some tubing they buy really cheap and simply refund those who complain (maybe 10%?).

Weird since B3 is a good known reputable company but this tubing issue is odd.

Kal
 
Just heard back from morebeer - They are sending me some replacement beer line. It is apparently from a different batch but I have my doubts.
 
Yes, please let us know how it works out. I just had them refund me for my line and bought stuff elsewhere.

If you want the Arrow stuff since you're in Ontario call up Simgo.com. You have to call to order (can't order online but you can look up stuff online). Horrible website so you need to know what you want. Their prices are incredibly low. If you're in Canada always look there first and nobody will beat their prices.

Kal
 
Hi Kal,

Too bad I didn't read your message before I went shopping today.. Just bought 40' of the Arrow 14 3/16" line for about $0.49 / foot at brewtime in hamilton. Oh well, at least I wont have stuff that smells and tastes like the morebeer stuff, and for me that is worth the extra price. Also I didn't have to pay shipping for the brewtime stuff as well.
 
So I got in the PET barrier Bev-Seal tubing 1/4" Id stuff in from Better Bottle and I've kegged my 1st batch.

I'm not picking up any plastic taint whatsoever

Although I'm having to really fiddle with the system to get it to balance. Being my 1st time I'm sure there's some learning curves but I'm currently @ 12-14 PSI (have played with it a bit) with 15+ feet of tubing and I'm getting a pretty foamy result with what I thought was a minimal amount of carbination...little over a week in the fridge.

I'm assuming it's my line length becasue since the Foam is present but the desired amounts of bubbles are not.

I wonder if it's partly in fact that i have coiled my serving lin up fairly compact like with bread ties and just reach in and pull oft he picnic tap? This stuff is pretty stiff so it seems like the best way to control the serpent
 

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