Metallic taste

[parrothead64]

I switched to fermenting in corney kegs and I love it. I can fit two in my chamber so I went from 5 gallons to eight gallons and can do closed transfers to avoid oxygen. I can also lower temp and add gelatin without sucking in 02. The problem is I sent a Lager into a competition and two judges said it had a metallic taste. I have done two batches like this and both were bad. Bad batches have been rare for me. I have never had two in a row. I bent the dip tubes in my fermenting kegs so I could only transfer clear beer into the serving keg. Is there anything I can do except stop fermenting in kegs?

 

[seatazzz]

Your kegs shouldn't be contributing a "metallic" taste unless they are scarred or have "rough" spots inside. According to Jon Palmer, other than iron leaching into the boil from your boil kettle or mash tun, the other cause of a metallic taste could be your malt. Do you do all grain, partial mash, or extract? What temperature is your wort at when you run it into the keg?

 

[parrothead64]

No rough spots. I thought there might be something exposed when I bent the dip tube. Until you mentioned it, I forgot that the wort was very hot going into the kegs,
My chiller broke as soon as I started to cool down. I transferred hot wort to kegs because I thought I could cool it down faster in an ice bath with two kegs than in one big boil kettle. That might be my problem. I do all grain Biab

 

[day_trippr]

That still shouldn't matter - if properly passivated stainless steel should be inert wrt wort.
Heck you presumably boiled the wort in stainless steel, if there was an intrinsic issue with hot wort and stainless we'd all be totally fooked

Cheers!

 

[parrothead64]

Boiled in aluminum but I have been using the same pot for years with no problems until now

 

[Lefou]

I seem to recall another recent thread regarding old or weak washed yeast as a possible culprit for metallic off-flavors.

Argh ...can't remember where to look for those thread comments, though ... it's been a couple days back and I just cleared out ALL my "watched threads".

 

[MaxStout]

Tell us about the water you're using. Are you building the water from RO or distilled, or are you using some tap water? Iron and manganese have a very low taste threshold in beer, and it only takes a few ppm to contribute a metallic taste.

 

[parrothead64]

I normally use bottled water from target. I did use a different brand than usual I think it was from Meyer.I didn’t do any water adjustments

 

[seatazzz]

May be talking out my a** here, but that may be your issue. Malt needs a certain amount of minerals to convert completely, your water should be slightly "hard" (alkalinic). If you used straight RO water with no adjustments, the mash may not have converted completely. Smarter heads, please comment?

 

[parrothead64]

I thought about that but my water sucks. We use a water softener. I have been using bottled water from Target since I started brewing. I have entered a bunch of competitions and never had anyone mention metallic before. The only things that changed were fermenting in a keg and using a different brand of bottled water. Could a different bottled water cause a problem?

 

[IslandLizard]

I normally use bottled water from target. I did use a different brand than usual I think it was from Meyer.I didn’t do any water adjustments

Bottled is not really a type of water. Is it spring water, distilled, or RO? Spring water may contain minerals from the source, such as iron, manganese, calcium, sulfates, chlorides, carbonates, etc. and can fluctuate with the seasons or source. Distilled and RO water are typically defunct of any minerals. Most "bottled" water is UV treated, but make sure they don't contain Chlorine/Chloramine as a preservative instead (use your nose or taste buds).

What level are those BJCP judges? Are you a member of a homebrew club, so you could get some more opinions on those beers. Do you taste anything metallic? Could it be from the bottling process? Oxidation in the early stages can reminisce a plethora of off flavors.

May be talking out my a** here, but that may be your issue. Malt needs a certain amount of minerals to convert completely, your water should be slightly "hard" (alkalinic). If you used straight RO water with no adjustments, the mash may not have converted completely. Smarter heads, please comment?

No, you're making a valid point. Now water can be very soft (low in minerals) and make some of the best lagers, e.g. Pilsner Urquell. It's the balance of the minerals and the resulting pH that affect the mash.