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Author Topic: Draught Line Freshness  (Read 2539 times)

Offline flbrewer

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Draught Line Freshness
« on: June 06, 2015, 05:11:38 pm »
I'm curious if it's a best practice to flush a pint (maybe less) of beer before serving before drinking kegged beer. My thought is that if I wait a week (hypothetically) between beers, there is beer just sitting in the beer line (most of which is chilled).

I'm just curious if it's unsanitary or at risk of spoiling when it's between the keg and my glass.


Offline Black Sands Brewery & Supply

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Re: Draught Line Freshness
« Reply #1 on: June 06, 2015, 06:28:05 pm »
i'd say there isn't a risk but i'd flush the line if it were a week.... but not if its only 1 day.

depends tho... if they line is new or clean then less risk of spoil or infection in the line... keep em' clean and you shouldn't have any issues.

all the bars i've worked at flush a few oz of each line at the start of each day just to get what was in the line over night out of a customers glass.
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Offline AmandaK

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Re: Draught Line Freshness
« Reply #2 on: June 07, 2015, 10:03:34 am »
If your beer lines and connections are clean and sanitary, it is sanitary in the lines over time.

That being said, when I had vinyl lines I would usually dump out the first 1/4 glass since I could taste the beer line (Micromatic 1/4" vinyl line, 12' length, through chilled remote tap box). Most visitors did not notice the taste, so it was probably just me being particular. I have since switched to barrier lines and have no beer line taste and do not dump any beer.
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Online tommymorris

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Draught Line Freshness
« Reply #3 on: June 07, 2015, 10:46:19 am »
If you fill a glass just enough to get only what was sitting in the line, you can taste that the beer sitting in the line is less carbonated.  Otherwise, I don't think beer sitting in the line spoils (just based on taste).

I serve and drink the beer from the line. It mixes with the rest of the pint and I can't detect any negative taste effects once mixed.

Offline HoosierBrew

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Re: Draught Line Freshness
« Reply #4 on: June 07, 2015, 11:27:59 am »
If you fill a glass just enough to get only what was sitting in the line, you can taste that the beer sitting in the line is less carbonated.  Otherwise, I don't think beer sitting in the line spoils (just based on taste).

I serve and drink the beer from the line. It mixes with the rest of the pint and I can't detect any negative taste effects once mixed.

+1.  Clean your lines thoroughly after the keg runs out each time and the beer won't taste spoiled IME. Just a little less carbed in the line. Not noticeably so if you fill a pint + glass.
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Offline a10t2

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Re: Draught Line Freshness
« Reply #5 on: June 07, 2015, 11:40:52 am »
I'd flush 2-3x the volume of any line length that sits warm, just to cool the line down for a proper pour. Starting with foam in the glass is going to waste more beer than pouring off that foam.

Fortunately, 3/16" line holds 0.2 fl oz per foot, so we're talking about a truly trivial amount of beer.
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Offline narcout

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Re: Draught Line Freshness
« Reply #6 on: June 07, 2015, 12:27:42 pm »
I'm curious if it's a best practice to flush a pint (maybe less) of beer before serving before drinking kegged beer.

It shouldn't be necessary.

That being said, when I had vinyl lines I would usually dump out the first 1/4 glass since I could taste the beer line (Micromatic 1/4" vinyl line, 12' length, through chilled remote tap box).

I used to have this issue as well, and it kind of drove me nuts.  I don't know if it was defective tubing or what, but after I changed it for the second time it went away.  I've changed my lines a few times since then (I try to do it once a year), and it has not reoccurred.
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Offline kramerog

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Re: Draught Line Freshness
« Reply #7 on: June 07, 2015, 03:28:26 pm »
I think that hoppy styles can go "stale" in the lines.  Perhaps the line itself ad- or absorbs some of the hop components.  Perhaps oxygen can permeate into the lines.  Since the volume of beer in a line is small, I found that dumping 2-4 oz of beer was sufficient to get the stale beer out.

Offline majorvices

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Re: Draught Line Freshness
« Reply #8 on: June 08, 2015, 08:02:36 am »
I think that hoppy styles can go "stale" in the lines.  Perhaps the line itself ad- or absorbs some of the hop components.  Perhaps oxygen can permeate into the lines.  Since the volume of beer in a line is small, I found that dumping 2-4 oz of beer was sufficient to get the stale beer out.

Yes, it is most noticeable to me on hoppy styles, but I can notice it on other styles as well. For me the little bit in the line can ruin the entire pint.

Offline maurer1933

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Re: Draught Line Freshness
« Reply #9 on: June 18, 2015, 05:11:41 pm »
I think that hoppy styles can go "stale" in the lines.  Perhaps the line itself ad- or absorbs some of the hop components.  Perhaps oxygen can permeate into the lines.  Since the volume of beer in a line is small, I found that dumping 2-4 oz of beer was sufficient to get the stale beer out.

Yes, it is most noticeable to me on hoppy styles, but I can notice it on other styles as well. For me the little bit in the line can ruin the entire pint.

Another thing to keep in mind is that even with regular alkaline cleaning of your beer lines, you can still get beer stone build-up. This can add a "stale" taste to beer as it sits in the line. It's recommended by the Brewers Association to clean your lines once every 2 weeks with alkaline/caustic and once every 3 months for an Acid cleaning. The acid cleaning can get rid of those pesky beer stones. As long as your line stays chilled, and you clean regularly, you shouldn't have to worry about stale beer. Oxygen permeation is very real though, and if your line is old it can get worse, if it is a major issue, try using barrier line instead of vinyl. Less flexible, but WAY better for preventing oxygen from getting in and also is fantastic for flushing lines. Next to no flavor transfer between beers when you switch kegs!


td;dr - Do an acid cleaning approx. every 3 months as well as alkaline/caustic every 2 weeks for freshest tasting beer. For persisting issues, change your lines, and consider barrier tubing.
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Offline flbrewer

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Re: Draught Line Freshness
« Reply #10 on: June 18, 2015, 06:17:42 pm »
I believe I'm using barrier tubing. E&J silver tubing.

Offline majorvices

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Re: Draught Line Freshness
« Reply #11 on: June 19, 2015, 04:06:05 am »
I don't find the need to clean every 2 weeks but 4-6 weeks is closer to my schedule.

Offline JT

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Re: Draught Line Freshness
« Reply #12 on: June 19, 2015, 05:13:30 am »
I clean em when the keg hits E and not before. 

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Offline maurer1933

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Re: Draught Line Freshness
« Reply #13 on: June 19, 2015, 01:31:24 pm »
If you're using barrier tubing you're already ahead of the game vs. ~70% of bars and restaurants. (Unless they have a glycol chilled long-draw system) So I'd say you're doing great! Unless you have a chilled beer line, you might want to flush it, simply due to the taste issue, otherwise you /should/ be okay.

For most at-home systems, if you're able to finish a keg in a few weeks then cleaning on E is fine, like Keith said, 4-6 weeks is appropriate. I was just stating the recommendations by the Brewers Association. You start getting intro trouble when you wait MONTHS before cleanings.
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