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  • Garden Hose Type Off Flavor

    I am getting an off flavor in my beers that I could use help diagnosing. I brew on a 3bbl system and we serve from 10 3bbl brite tanks directly to the bar (brewpub). The easiest way to describe it is a garden hose flavor (Chlorophenol?) The flavor is not at all present when the beers are in the fermenters but appears after the beer has been in the bright tank for about a week. I am using Birko cleaning products and PAA to sanitize.

    The trouble I am having is that it only appears in some of our beers. Oddly enough it has not really appeared in lagers or the Cream ale we always have on tap. It is consistently in our pale ale and I am starting to get it in our IPA and noticing it in a porter on tap. The pale and IPAs are dryhopped but still the flavor is not apparent in the fermenters and takes some time to appear in the brite's.

    Possible explanations:
    1) I am using a regular garden type hose to rinse out the CellRMastr cleaning solution. However after this step we run the PAA and do not do a rinse after this step. Also it does not appear in every beer so I am a bit skeptical this is the issue. (Plan to get a proper washdown hose for this anyway)
    2) Infection: This must be happening on the way to the brites but skeptical of this because once again its not every beer.
    3) Gravities have been finishing 1 or 2pts higher then I want and finished beer PH is usually a touch higher then I would like. 4.4-4.7. I dont think either of these would be the source of the flavor.
    4) Water. In NYC the water is very soft like Pilsen. I am adding Gypsum and CaCl to the mash to get my calcium, sulfate and Chloride into appropriate ranges. I suppose I am using more of these salts in these hoppier american beers and that could be whats causing it? But I would think I would detect it earlier then it going into the brites.
    5) I am using clear PVC tubing to transfer from Fermenter to Brites using CO2 pressure. But its rated for Food and Beverage. If this was the issue once again I think it would be in all beers. Specific tubing here: http://www.mcmaster.com/#catalog/120/124/=v3bnby

    ANY OTHER IDEAS?

  • #2
    A few other areas to look at:

    -Are you taking steps to remove chlorine from your water source? The presence of chlorine carried into the ferment can certainly create chlorophenols in the finished product. This could be accentuated with different yeast strains/beers

    -Are all hoses and transfer lines that see high temperatures rated for those temps?

    -Taplines/serving lines from your BBT to the bar - dirty tap lines can create all kinds of off flavors, not just diacetyl. Are you perceiving the off-flavor in the glass at the bar or directly out of the BBT?

    -If it is being perceived in the glass only after being poured from the faucet is it due to glassware cleanliness/residual sanitizing agents on the glass?

    -And this one is a stretch...but is there a common hop used in the beers that are exhibiting this off-flavor? I perceive an odd phenol/plastic character out of most beers that use EKG in late additions. Again, this is my palate (and a few others I've talked to) but generally looking at the make-up of the beers you might be able to trace it to an ingredient issue. However, if this flavor comes and goes at irregular intervals I would look much more closely at the process side of things.

    Hope these can spark some ideas

    -Tom

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    • #3
      Are you using a common yeast strain for the the beers to give off this flavor? Have you tried using a new pitch of yeast?
      Troy Robinson
      Quirk Brewing
      Walla Walla

      Comment


      • #4
        carbon filter or pvc

        I will add my ditto to checking on chlorine removal. Carbon filtration should take care of it under most circumstances.

        The other thing I would look at is the PVC tubing. We came across an issue with some lengths of pvc lines we had in our serving system that we determined were contributing off flavor. The tubing was rated food grade under the NSF-51 standard, but as we found from talking to tubing and chemical suppliers that it just means that the compounds are safe for food contact and is fairly broad in its scope.

        We received some helpful feedback from an engineer at a tubing supplier, they noted that the chemicals used to clean the lines will be absorbed into the tubing surface and then desorbed. The problem is exacerbated by alcohol which will extract the plasticizer, carrying with it and absorbed compounds. The effect will depend on residence time and surface area. The effect may come and go, but it will always return.

        Since the effect seems to be brand to brand, the tubing may not be the issue if you are using the same tubing for all brands. That said, we noticed the off-flavor intensity varied among different brands.

        Comment


        • #5
          Originally posted by WaterEng
          That does make sense. However, that sort of tubing is pretty common in serving systems. Is there guidance on what to look for (or avoid)?

          The common line cleaners are strong caustics which should generally impart ionic components in the lines and I would imagine are quickly flushed if an acid-based sanitizer is subsequently used. Clearly, avoiding a chlorine-based cleaner or sanitizer makes sense. Does anyone use chlorine-based products in their serving line maintenance?

          I have gotten a bad batch of vinyl tubing before. It expressed itself with a strong plastic flavor in the beer that was served through it, no matter how much I cleaned it. I called Foxx, they said they had gotten numerous complaints about that batch, and they replaced it for me with a good batch of hose.

          I tasted it at another local brewery as well, and coincidentally they also had just recently replaced their lines with it.

          It happens. But I am not so sure that is the OP's problem.

          Comment


          • #6
            +1 for vinyl/pvc beer line being the problem. when we were building our taproom we got beverage grade vinyl from beverage factory... luckily it was long enough away from our opening so i could do research and order different beer lines. The beer that came out of the vinyl hose had a very distinct plastic taste that was especially apparent if the beer sat in the lines for any more than a few minutes. After researching i found homebrewers talking about how they were using PET 'barrier" tubing with good results. It actually has many advantages over vinyl and pvc including: It is much cheaper, you can get 100 feet for 20 bucks from fox. It is a harder material and therefore absorbs and desorbs less. It imparts ZERO plastic taste (its the same material water bottles are made from). It is smoother and harder than pvc or vinyl so it theoretically would need less cleaning, and would clean much easier. The one disadvantage you will hear is that it is hard to work with. It definitely is tougher to work with, but if you make sure to have 3/16 barbs on your keg coupler and shank you should be able to just dip the hose in boiling water for a bit and slide it right on the barb. Another thing to consider also: because it is smoother and harder than vinyl/pvc, it will also create less resistance than regular 3/16 beer line. Because of that we're using about 15 feet of it to maintain good carbonation at 12 psi.

            After using barrier tubing for a few months I dont know why vinyl and pvc are even an option. I definitely dont want to spend so much effort in brewing and have it all go to waste because of plastic off flavors from the 10 feet of beer line it goes through before its served. I know some "batches" of vinyl and pvc will have satisfactory results with below threshold plastic levels but why risk it when barrier tubing is cheaper. I also don't know if the beer line is the OP's problem but if your going through a process of elimination to solve the problem i would highly suggest switching to barrier tubing

            Comment


            • #7
              Originally posted by ChrisKennedy View Post
              I have gotten a bad batch of vinyl tubing before. It expressed itself with a strong plastic flavor in the beer that was served through it, no matter how much I cleaned it. I called Foxx, they said they had gotten numerous complaints about that batch, and they replaced it for me with a good batch of hose.

              I tasted it at another local brewery as well, and coincidentally they also had just recently replaced their lines with it.

              It happens. But I am not so sure that is the OP's problem.
              It seems that the most recommended option for serving lines are the vinyl barrier tubing options out there. Some are more elaborate than others. From what we have learned they are more resistant to off-flavor issues and their gas permeability is much lower so there is less CO2 loss or O2 pickup. There are some micro-resistant versions that provide some additional utility beyond the tubing's inherent strength.

              In the cellar and other process areas, chlorobutyl tubing is a fairly ubiquitous product. The grey Goodyear brewery/vintner hoses often seen splayed across brewery floors are chlorobutyl-lined hoses. They are used in a wide variety of FDA-approved applications and are easy to keep clean, limit pickup and have minimal gas permeability.

              Matthew

              Comment


              • #8
                Originally posted by ChrisKennedy View Post
                I have gotten a bad batch of vinyl tubing before. It expressed itself with a strong plastic flavor in the beer that was served through it, no matter how much I cleaned it. I called Foxx, they said they had gotten numerous complaints about that batch, and they replaced it for me with a good batch of hose.

                I tasted it at another local brewery as well, and coincidentally they also had just recently replaced their lines with it.

                It happens. But I am not so sure that is the OP's problem.
                It seems that the most recommended option for serving lines are the vinyl barrier tubing options out there. Some are more elaborate than others. They are more resistant to off-flavor issues and their gas permeability is much lower so there is less CO2 loss or O2 pickup. There are some micro-resistant versions that provide some additional utility beyond the tubing's inherent strength.

                In the cellar and other process areas, chlorobutyl tubing is a fairly ubiquitous product. The grey Goodyear brewery/vintner hoses often seen splayed across brewery floors are chlorobutyl-lined hoses. They are used in a wide variety of FDA-approved applications and are easy to keep clean, limit pickup and have minimal gas permeability.

                Matthew

                Comment


                • #9
                  Its in the lines

                  Thanks for all the feedback and sorry I have not replied sooner. I have figured out its the lines since I do not get the flavor right from the tanks and it usually goes away after a pour or two from the taps. The lines are currently only cleaned once a month which seems pretty minimal so I need to talk to the owner about having it done at least every 2 wks. We have also had most of them for five years so it may be time to change them out completely. Ill update if I find out more info.

                  Cheers,
                  Patrick

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