Question on process

[quich38]

Hi all,

just looking for tips on taking our beer to the next level. I think we may be picking up some medicinal flavors during our fermentation and just wanted to get some input. i will tell you what we do now:

using 3.5bbl plastic conicals in a temperature controlled room set to about 69 degrees (not crashing or filtering at all) and this is our process:

pump 75 degree wort in and add yeast half way during pumping
let sit and ferment for 1-2 weeks
drain yeast from the very bottom of fermenter
lets sit for another week and dry hop depending on style
At this point the yeast has for the most part settled below our kegging port.
we then keg the beer right from the FV and force carb for a week or so before drinking.

we clean our FV's with a rigged up CIP ball at the top cycling PBW rinse, rinse off any left over crud and then star-san the entire inside. Also washing our kegs with the same chemicals.

For the most part the beer is turning out great.....every now and then we get some medicinal/band-aid flavors and just wondering if anyone has suggestions on improving upon our process...

thanks for you help!

[william.heinric]

Wort Temp

You're pitching at 75F? That seems high to me. I get higher fusels with higher pitch temps, and I've noticed that I get noticeably worse hangovers from warmer pitches. That could be your Band-Aid flavor.

What about your water? Is the chlorine being effectively removed?

Bill

[KaskaskiaBrew]

Agree with Bill. I'd definitely tackle the fermentation temps and the Chlorine. Don't forget that the yeast on that size fermenter puts off a ton of heat so even though your temp is set to 69, your beer may be getting up into the low to mid 70's? You may find that you need to crank the cold room down to 65 or so to actually hit a fermentation temperature around 69. Stick a temperature probe in the fermenter just to be safe that the temperature you're trying for is the temperature you're getting. To remove the chlorine, you could always fill the kettle the night before with water and let the chlorine naturally remove itself through the air. It's simple and pretty effective assuming your starting water doesn't taste like it came out of a swimming pool.

I had a band-aid/metallic flavor in some homebrewed beers that I fought for about 3 months a few years back and that flavor popped up when I switched from gas to electric elements to heat the brew kettle. The elements were actually forming rust during the brew and that iron was soaking into the beer. I'm not sure what sort of system you have but if there is any rust anywhere, it could also be the culprit. Just another thing to check for.

Cheers

[quich38]

Thanks for the input so far guys. I was just talking to our head brewer as he knows more about what step temps we are hitting. I was a little off in that we are down to around 68-69 for yeast pitch. As far as fermentation temperatures go that's a little up in the air as we cant really cool individual tanks that are in active fermentation. Our tanks currently are not outfitted with any sort of temp gauge so its hard to say exactly more so then that they don't feel warmer then they should. As we are small and money is tight, the plastics are just what we have right now and we cant do a lot of things metal tanks can do ( hopefully that will change in the near future).

As for chlorine, we don't have any fixed data on that except for that fact I will say our local water is very good tasting water. Deff does not taste like pool water.

We do get some slight rust deposits around our elements, which every few brews gets heavily cleaned. This could be a possible source? Our head brewer has been concerned with pbw residue remaining in the tanks and causing the metallic flavor we sometimes get.

We have been running about 75% of our beer with dry yeast, so the concern there is that we are not getting as good of quality fermentation.

[KaskaskiaBrew]

Hey Quich, I'm in the same boat so I can completely understand where you're coming from. You could maybe try drilling a hole through the top and using a long 20" thermocouple to get an accurate temp if you really wanted to. Just a thought.

Anyway, those heating elements are the devil. I have fought and fought them over time and there was no way to ever keep them from rusting. I could buy a brand new element and it would be rusting after the first batch. It seemed like they would always toss a metallic flavor into the beer. I finally found the solution and took the water heater approach. I added a magnesium anode to the kettle to act as a sacrificial lamb. The acidic wort will eat the anode instead of the heating element and the small amount of magnesium in the beer is good for the yeast. I can't remember where I bought it but I'm sure you can google one. I think it was about a 4'' magnesium anode with a 1/2'' threaded end on it and I threaded it through a tri clover fitting. It's been about 50 batches and the element doesn't have a bit of rust on it. Plus the metallic flavor also went away. Maybe try that out and see if it solves your issues.

Cheers

[InBrewTown]

Is your brewing water from a municipal source or is it well water? If it's muni, it's probably treated with chlorine (as is Milwaukee city water).

We don't have a water filter coming in to our brewhouse, so I preheat all of our brewing water to 176F the day before brewing. This will allow all of the chlorine to evaporate off. Haven't had a problem with medicinal flavors.

Also, what are you using to sanitize your fermenters? I avoid iodine-based sanitizers for the reasons you state.

Good Luck!

Scott

[quich38]

fermenters are cleaned with pbw, and then sanitized with starsan

[froptus]

There are usually 3 reasons for a medicinal/phenolic taste in your beer.

1. Poor water quality. Water contaminated with chemicals. Yes chlorine could be one of them. However this is the least likely cause.

2. Excessive use of iodine based sanitizer. Reduce the concentration. This is relatively unlikely though if you just follow the manufacturers instructions.

3. Wild yeast infection! This is most likely especially since you're using dried yeasts which are notorious for this. Use a real yeast from White labs or Wyeast and begin and maintain a proper yeast cultivation and management system.

Good luck.

[panadero]

Never had this problem with dried yeast. Sounds like temperature to me, but could be a sanitation issue. About to start using same said plastic tanks, and my understanding is to completely take them apart each time, and use no metal scouring pads on the inside. If you can chill to 60 degrees, I think the temp rise during fermentation may not rise quite as high.
Good luck!
David

[callmetim]

We also use plastic conicals. Pitch at 72 but the fermenters are kept in a 65 degree room. I don't have temp probes in the fermenters but when I first started I checked the temp on several batches and found the temp would stay pretty steady at 72 for 48 hours or so then reduce to 65.

I also use dry yeast US-05. it is extremely consistent. I do notice more phenols at higher temps however especially if we use WB-06.

I would look at temp first - not pitching temp as much as fermentation temp. also pitch rates.

[quich38]

I just checked the temps on two batches that are in active fermentation. From the samples I pulled one was at 71 and one was at 74. So the fermentation temp is a little bit high. These batches are on white lab strains (wlp001, and wlp002) but we do still use a lot of us-05 for other beers. The other fermenters in the room that are not in active fermentation are showing about 65. I have the heater in the room set to 67 currently.

I guess I just dont really have a way to cool tanks that are actively fermenting. If I let the whole room get colder the tanks that are not in active fermentation will get to cool.

Will fermentation temps of say 74 degrees cause metallic or medicinal flavors?

[AMS0286]

Cooler room, temp controllers, heat tape

I have purchased the same Den Hartog brand inductor tanks that you are using, however they are the INFD-110-30 110 gallon models. My plan, as they have not yet been put into operation yet, is to place them all in a temperature controlled room, down towards the 60 degree F mark. What I will be doing differently is adding a temperature controller and pipe trace heat tape to each unit. I can then set the temp controller to 66 degrees F and wrap the unit with the heat tape. I will allow the ambient temperature to fight the heat created by fermentation while still allowing for enough ambient heat to make it possible for the heat tape to keep the temperature high enough for uniform fermentation temperatures. This should allow me to control each unit separately vs. just one heater in the entire room to control only the ambient temps. Has anyone else out there attempted something similar. I know I have read a few threads where people submerge stainless coils in their actively fermenting wort, but I don't like the idea of doing that, or overly modifying these plastic fermenters. I have successfully employed this strategy at home in the cellar, and I don't see why it couldn't work at this volume.

[froptus]

Temperatures of up to 74 F will not cause metallic or medicinal flavors in your beer. It wont cause any negative flavors. At that temp. your beers will just have more esters and usually taste more fruity which can often be a good thing. We're talking about ale yeasts here and there may be rare exceptions to this rule.

High fermentation temps (78 and above) can result in the production of fusel alcohols which taste like solvent (paint thinner)/acetone (fingernail polish remover). Even those flavors usually wont occur unless all of the fermentation happened at those high temps.

I once forgot to turn on the cooling jacket for a 50 bbl batch I had just brewed. I came in the next morning (16 hours later) and the temp was at 84 F. I chilled the beer to 68 and that beer ended up tasting just fine.

Troubleshoot the problem more. Is it occuring in all batches? (Possible water problem). Is it only occuring in some batches? (Possible yeast problem). Start with fresh pitches. How many generations are you using your yeast? Healthy, clean yeast can become infected with wild yeast from the air and eventually grow to the point where it affects the flavor of your beer.

Good Luck.

[WitsEnd]

Medicinal or band-aid comes from chlorine/chloramines or infection.

If you're not carbon filtering or otherwise treating a municipal water supply, you may get this. Some water supplies vary in chlorine and may give the supply an extra dose from time to time if they detect issues.

[quich38]

I believe we have 2 off flavors occurring only sometimes. Once in awhile we get a slight medicinal flavor in some batches. These batches primarily use dry yeast, and are new pitches each time.

More frequently we are getting the metallic flavor, which is more apparent in some batches then others. Also some batches it is not detectable.

So here are some things I am going to be looking into changing, let me know if you guys suggest anything else...

1) The use of an anode to stop corrosion on my heating elements, and possibly rust/iron in the brew kettle
2) Switching off the use of Dry Yeast (s-05, s-04)
3) Watching temps during fermentation, although I don't have a good way to control them right now
4) although I dont think we have much of a chlorine content, look into charcoal filtering