Consistent Off-Flavor in my Centennial Blonde

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Guidry

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Location
Denham Springs, La
I am having a problem with an off flavor I keep getting in my centennial blonde brew. See the post below for details.

https://www.homebrewtalk.com/f66/centennial-blonde-simple-4-all-grain-5-10-gall-42841/index251.html#post4697299

It was recommended that I post my brew process and equipment and maybe someone could spot a possible cause.

Here is my brew process, I can go into more detail if you see a possible problem:

1. Heat strike water in large kettle (Aluminum)
2. Heat mash tun (Rubbermaid 10 cooler style) with hot water
3. Crush grains (gap set to approx .035”)
4. Drain hot water from tun, add strike water at predetermined temp
5. Add grains while stirring. Measure temp and close lid on tun.
6. Heat sparge water (batch sparge)
7. Vorlauf and drain first runnings into SS boil kettle
8. Add sparge water and stir
9. Drain remaining volume
10. Heat to rolling boil
11. Add hops at predetermined intervals
12. Added immersion chiller at approx. 10-15mins remaining in boil time
13. Shut off flame at end of boil time
14. Chill to approx. 70 degs
15. Take starting gravity reading
16. Siphon into carboy
17. Pitch rehydrated yeast into carboy
18. Move carboy to “swamp cooler” in dark room, cover from light
19. Wait until airlock activity ceases and take gravity reading
20. 24 hrs later, repeat gravity reading until no change
21. Siphon beer to keg

My equipment is:

Heating kettle: 12gal aluminum kettle
Boil kettle: 8gal SS kettle
Mash tun: 10gal Home Depot round cooler with SS mesh braid
Fermenting vessel: 6.5 gal glass carboy
Chiller: 50' copper IC
Fermenting cooler: Igloo CUBE swamp cooler

Any ideas or questions, I'll be happy to elaborate on what I normall do.

Thanks.
 
You say your getting soapy & metallic flavors? All looks ok to me. Do you know your water profile? Mash PH? Whats your sanitation procedure? Starsan?
What beers do you normally brew that turn out ok?
 
I have heard of taps contributing to a metallic taste. That's another area I would check.
 
Copied from the water profile:

pH 8.5
Total Dissolved Solids (TDS) Est 200
Electrical Conductivity, mmho/cm 0.33
Cations / Anions, me/L 3.5 / 3.4ppm
Sodium, Na 80
Potassium, K < 1
Calcium, Ca < 1
Magnesium, Mg < 1
Total Hardness, CaCO3 3
Nitrate, NO3-N 0.1 (SAFE)
Sulfate, SO4-S 3
Chloride, Cl 5
Carbonate, CO3 9
Bicarbonate, HCO3 166
Total Alkalinity, CaCO3 151
"<" - Not Detected / Below Detection Limit

I have no idea on the mash pH.

This beer is the only one I have noticed this flavor with. I usually brew IPAs and stouts/porters, which I guess could hide the flavor.
 
I use an oxyclean solution for cleaning and starsan for sanitizing.

I've beent reading some of the brewing sites and it mentions that BOILING in an aluminum pot may cause metallic flavors. I do not boil in one, but I heat my strike/sparge water in one. I may heat some up tonight, let it cool and see what it tastes like.

One other idea is that I use the plain vinyl clear tubing to drain my wort from the tun to my kettle. The specs say it is ok up to 175degs and that it can be used for beverage dispensing. Could some flavor be coming from that?

@Mojzis: I tasted last night direct from the carboy/gravity sample, so no tap has entered the picture.
 
I use the same tubing with no issues. I doubt its that unless you were sold a different brand then labelled. Sounds like it could be your kettle. I have heard not to use oxyclean with aluminum or chlorine with brass.

Also what shape is the kettle in? Heavily oxidized, relatively new...etc?
 
You think it could be my kettle I use to heat the strike water? Ya think even at temps <180degs, the flavor could be produced?

Now that you mention, maybe the cleaning with oxyclean removed the oxidation from the aluminum. I remember reading somewhere how to "recondition" the aluminum....Going look for that text.
 
I heat my strike water and boil my wort in an aluminum pot and have never had an issue. I don't wash the pot other than rinsing and wiping down with a nylon scrubbing pad though.

Soapy flavor may be that you aren't rinsing well enough.

Is the metallic taste astringency?
 
I have pretty much the exact setup and was getting a twangy taste like that. I started using spring water instead of our home water even though I was putting the pills in it to make the water taste right and it went away when using the spring water from walmart
 
Could this just be a "green beer" taste that will subside in a few weeks? Perhaps it shines through more so with this lighter-side beer than your others. How long will this taste persist if you leave a bottle/keg?
 
I would look into your HLT even though I doubt it is the cause.
EDIT:
Do you clean you HLT with oxyclean? This may oxidize the aluminum and cause flavor problems.

If you dont notice the flavor in your other beers. Your water has a high PH and the darker beers can lower that PH to optimal levels unlike this blonde. Do you use any water salts/water software? Usually astringent flavors are noticed from high PH/tannin extraction but this is all I can see that could be a problem since you don't have the flavors in your other beer.
 
@stpug: While this latest batch is just out of the carboy, the previous batch was over 2 months in the keg, and if anything, got worse. I finally ditched the last 2+gals.

@CGVT: I would be extremely surprised if not rinsing enough is the culprit as I would say I over-do that part of it, plus I use Starsan as a sanitizer which is supposedly a no-rinse sanitizer.

I might say there is a small astringency element to the taste. I originally described it as "iodine" to my wife who then suggested "soapy" which I probably would say fits it better. I recently read that overmilling can lead to an iodine flavor.

Anyone see anything peculiar or out of line with the water profile? I don't know much about that part of it yet.
 
19. Wait until airlock activity ceases and take gravity reading
20. 24 hrs later, repeat gravity reading until no change
21. Siphon beer to keg
Sounds like you have a yeast mutation problem.

An airlolck slowing down plus 24 hours is probably not enough time for the yeast to adequately clean up after themselves. Any light ale, blonde ale, kolsch etc....will be much more sensitive to off flavors as the flavor and aroma profile are so mild.

Next time try getting back to some simple basics.

Give your beer two full weeks in the primary.
Rack it to a secondary with gelatin.
48 hours in the secondary and it should be clear as a bell and ready to rack to a keg.

Let the yeast have adequate time to clean up after themselves....then do what you can to clear that yeast out of the beer before kegging.

Also...make sure (and I speak from bad experience) that you are keeping crushed grains and grain dust away from your post boil wort. :mug:
 
You think it could be my kettle I use to heat the strike water? Ya think even at temps <180degs, the flavor could be produced?

Now that you mention, maybe the cleaning with oxyclean removed the oxidation from the aluminum. I remember reading somewhere how to "recondition" the aluminum....Going look for that text.

I use an aluminum pot to heat my strike water. It used to be my brew kettle before I upgraded to a 10-gallon system. I don't think that's your problem. I think it's the high alkaline water. I have had the same problem since we moved 3 years ago. Every one of my beers were pale ales and there was this consistent off flavor similar to what you describe, in every one of them. Then I brewed a brown ale that turned out to be FANTASTIC. I've been studying water chemistry/residual alkalinity and I'm fairly certain that the high alkalinity of my water is to blame. The darker grains are more acidic and will lower the mash ph. That's why my darker beers turned out great. You said you didn't notice it in your porters or stouts and I'm guessing you didn't notice it in your IPA because of the amount of hops masking it, maybe? If your water tastes good and your darker beers are fine, try adding some gypsum to the mash and kettle for your paler beers. Using Five Star 5.2 pH Stabilizer might work, too, but it isn't cheap. Other people swear by it, though. You could also try using bottled spring water just for your paler beers.
 
Sounds like you have a yeast mutation problem.

An airlolck slowing down plus 24 hours is probably not enough time for the yeast to adequately clean up after themselves. Any light ale, blonde ale, kolsch etc....will be much more sensitive to off flavors as the flavor and aroma profile are so mild.

Next time try getting back to some simple basics.

Give your beer two full weeks in the primary.
Rack it to a secondary with gelatin.
48 hours in the secondary and it should be clear as a bell and ready to rack to a keg.

Let the yeast have adequate time to clean up after themselves....then do what you can to clear that yeast out of the beer before kegging.

Also...make sure (and I speak from bad experience) that you are keeping crushed grains and grain dust away from your post boil wort. :mug:

The only thing BierMuncher stated that I don't do is secondary or gelatin. I get my beer to clear by cold crashing. But that's after 2 weeks minimum in primary. 3 weeks is even better. THEN I cold crash for a day or 3, rack to keg and let sit on serving pressure for a week or so before serving (no force carb). Most of my beers are at least a month old before they're served. Really hoppy beers even longer.
 
Sounds like you have a yeast mutation problem.

An airlolck slowing down plus 24 hours is probably not enough time for the yeast to adequately clean up after themselves. Any light ale, blonde ale, kolsch etc....will be much more sensitive to off flavors as the flavor and aroma profile are so mild.

Next time try getting back to some simple basics.

Give your beer two full weeks in the primary.
Rack it to a secondary with gelatin.
48 hours in the secondary and it should be clear as a bell and ready to rack to a keg.

Let the yeast have adequate time to clean up after themselves....then do what you can to clear that yeast out of the beer before kegging.

:

The previous batch of this beer sat for well over a week in the primary and then, because I wasn't in a hurry, I put it in the secondary for a week, including 3 days in the fridge to try and clear it. It never cleared. This one seems very cloudy also. This batch used Danstar BRY-97, the previous had US05.

I brewed this as a last minute idea for a work Christmas party. Unless something changes drastically, I'll be bringing a keg of stout I have instead.
 
I'd agree with those who have you looking at your water. I have pretty high pH and high bicarbonate water myself. I was having similar issues on my pale beers when using solely my house water.

I spent several weeks over on the brew science forums and the guys over there helped a lot. I now use a mix of my water and distilled water. I use some of the pH reducing salts like CaCl and gypsum to replace what I take out by going with distilled water. For my very pale beers like the Lawnmower beer I keep around for some friends, I even go so far as to toss in a little acid malt to adjust my mash pH.

With water like yours (your pH is even higher than mine), you really need to get the carbonates and pH under control. And decent pH meters can be had for under $80. Well worth it if you're tossing beers that develop any of these flavors.
 
I'm sticking with my original thought of PH. I just plugged your water profile and BierMuncher's centennial blonde recipe into EZ water and found your mash PH to be way to high at 5.79 and it should be 5.4-5.6. You should look into using Lactic acid and brewing salts to bring your profile within limits.
 
The only thing BierMuncher stated that I don't do is secondary or gelatin. I get my beer to clear by cold crashing. But that's after 2 weeks minimum in primary. 3 weeks is even better. THEN I cold crash for a day or 3, rack to keg and let sit on serving pressure for a week or so before serving (no force carb). Most of my beers are at least a month old before they're served. Really hoppy beers even longer.

I rarely secondary these days....usually strainght to keg (but always with gelatin). I'm just looking for some an extra step that may clean up the taste.

If the OP has his original dip tubes in his kegs and racks straight to keg, it could also be that he's drawing out enough yeast sediment to throw the flavor of the beer off. That's why I removed all my dip tubes and gave them a slightly sharper bend...to get that end about 1/2 inch off the bottom.
 
If those don't work, try discarding the first 3-4oz of beer from each night that you pull a draft beer. I have pharma grade tubing for my keg system and all SS parts and perlick faucets, but the first 3-4oz coming out of the keg ALWAYS taste funky. Try that and see if you get the true flavor you are looking for.
 
OK, all of this talk about mash water pH has brought me to another piece of the puzzle which might make a lot more sense now. I have brewed this beer before using extract and it came out fine. Does that make logical sense? I gotta start studying water chemistry now.
 
there you go. You cant extract tannins from DME/LME. Your getting your off flavors from your mash.
Read palmers How to Brew. especially chapter 15 here (older version).
You can use any water profile spreadsheet off the web. I started with EZ water and now use Bru'n Water
 
Your water appears to be from a softener. Higher than normal sodium and very low calcium/magnesium. I have very low cations in my water and it always took three or more weeks for my beer to be drinkable. Since I started adding salts to get my calcium above 50 ppm I can try (and say wow) my beer around 4 days. I know it's not fully carbed but it's way better than before water additions.

The other thing I notice about you water is the Bicarbonates are high, which will lead to a high mash PH. I don't know what the high sodium levels will doo to your flavor, but I suggest you read about water chem. and at least add a tsp of gypsum and caciulm chloride to your mash.
 
One more thing.

I really like Kaiser's water calculater

Brun water is good also, though I haven't used it as much.

I do not really like Palmer's EZwater though. He put too much emphasis on RA and I think RA is a result of the other factors. Plus it doesn't have a spot for table salt (NaCl) which can be used to increase chlorides which will effect beer flavor but not mash PH or RA.
 
If you are using softened water, STOP. A water softener removes calcium and magnesium, which can be beneficial, with sodium, which is undesired at high levels.
 
I'm not sure if anyone has mentioned this.... but are you somehow removing the chlorine/chloramine from your water? It does look like you are using softened (bypass this) municipal water (which will have some disinfectant in it). That was my first thought before even getting to point #2.

I light delicate style will leave chlorophenols nowhere to hide. I am sensitive and can pick them out like a kick to the face. See the sticky in the Brew Science forum about Campden tablets. This is a quick and easy route to eliminate chlorine or chloramine in seconds.
 
Also, don't just calibrate your thermometers in ice water and boiling water. Calibrate your HLT thermometer to 170, your MLT thermometer to 150, and your BK thermometer to 65. You'd be surprised how far off even a "nice" thermometer can be in the middle of the range. If you're not certain of mash pH, a combination of oops-I-just-sparged-at-190 could mean a nice tannin beer.
 
GotPushrods said:
Also, don't just calibrate your thermometers in ice water and boiling water. Calibrate your HLT thermometer to 170, your MLT thermometer to 150, and your BK thermometer to 65. You'd be surprised how far off even a "nice" thermometer can be in the middle of the range. If you're not certain of mash pH, a combination of oops-I-just-sparged-at-190 could mean a nice tannin beer.

It was my understanding that at the time of sparging, all conversion has already taken place so tannins aren't an issue. Ive personally sparged with near boiling water with no negative effects.
 
It was my understanding that at the time of sparging, all conversion has already taken place so tannins aren't an issue. Ive personally sparged with near boiling water with no negative effects.

Tannins are not related to conversion, they are a polyphenol in the husks of the barley. Increased temperature and pH make them more soluble, and more easily extracted into the wort. Their pKa is quite high, and need a higher pH to really become a problem.

I've tasted a very tannic beer before, and it's quite apparent. You can, fortunately, fine out a lot of it with a combination of gelatin and PolyClar (PVPP) if that is the problem.
 
GotPushrods said:
Also, don't just calibrate your thermometers in ice water and boiling water. Calibrate your HLT thermometer to 170, your MLT thermometer to 150, and your BK thermometer to 65. You'd be surprised how far off even a "nice" thermometer can be in the middle of the range. If you're not certain of mash pH, a combination of oops-I-just-sparged-at-190 could mean a nice tannin beer.

Ok, I know how to calibrate to the extremes, but give me some ideas on calibrating to the temps in the mashing ranges.
 
Ok, I know how to calibrate to the extremes, but give me some ideas on calibrating to the temps in the mashing ranges.

You just need a reference thermometer that you trust. Ideally you'll find a lab mercury or alcohol glass thermometer. But if you have a 2 or 3 digital thermometers at home that all more-or-less agree, that will work for now. A meat thermo, BBQ wireless thermo, pH probe temperature readout, whatever you have. Borrow something if you need to. A ThermaPen would be great if you know someone that has one.

Bring a pot of water to 150 according to your reference thermometer and adjust your mash tun thermometer accordingly. It may now be off at freezing and boiling, but who cares!
 
stpug said:
could this just be a "green beer" taste that will subside in a few weeks? Perhaps it shines through more so with this lighter-side beer than your others. How long will this taste persist if you leave a bottle/keg?

+1
 
I'd wager it's almost certainly the high sodium level + high alkalinity. You shouldn't be brewing with water from a softener.
 
We do not have a softener installed at my house. At least not one I am aware of. The water in our area is known to be soft. Taking a shower usually requires as much work to get the soap off as it does to scrub off the dirt.
 
We do not have a softener installed at my house. At least not one I am aware of. The water in our area is known to be soft. Taking a shower usually requires as much work to get the soap off as it does to scrub off the dirt.

That's odd looking water then. I wouldn't brew with it, personally (I'd get RO water from the grocery store.). It looks like all of the reports I've seen from softened water. Are you near the ocean? Also, regardless of the source, your alkalinity is much too high for blonde beer like this. It'd be easier to use RO.

EDIT: N/m, I see you're not near the ocean.
 
OK, I've posted my process and equipment in a separate thread as to not hijack this one. Anyone who feels like trying to help, my new distress thread is at:

https://www.homebrewtalk.com/f36/consistent-off-flavor-my-centennial-blonde-375255/#post4698398

When was the last time you took your mash tun apart and cleaned or replaced any crusty looking parts? I just had a couple batches in a row taste like what youre describing. I rebuilt my tun using all stainless parts instead of the brass stuff cuz it had some nasty stuff building up in and around the valve and rubber washers.. first batch after rebuilding it tastes back to normal again..
 
Use campden tablets to get rid of the chlorine/chloramine in your water. Add 1 to 2 tsp of gypsum to up the Ca level. That ought to do it. I ran into some of the same problems you mentioned for quite some time as the water where I am at is somewhat low in Calcium. Good luck.
 
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