Unpleasant/bitter flavor on the back of my tongue from BIAB in AG batches, post fermentation

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I was using a quarter of a tablet for 5 gallons pre-boil. I may try RO water on this next batch and possibly a smaller batch with tap water and leave it out over night with the campden added in.

RO water is perfect, especially for light colored beers like Spotted Cow.
I have great tasting water, but it's got a high bicarb level due to where I live so I had to switch to RO water myself for the light colored beers I like to brew.

The only beer I can make well with my tap water straight is stout! Even then, my mash pH is 5.56 or so, with the blackest most acidic grains. Making a light colored beer, I've measured a test mash as high as 6.0 with my tap water.
 
RO water is perfect, especially for light colored beers like Spotted Cow.
I have great tasting water, but it's got a high bicarb level due to where I live so I had to switch to RO water myself for the light colored beers I like to brew.

The only beer I can make well with my tap water straight is stout! Even then, my mash pH is 5.56 or so, with the blackest most acidic grains. Making a light colored beer, I've measured a test mash as high as 6.0 with my tap water.
I think I have moderately high hardness in the tap water here, luckily there is a grocery store selling RO water for .34 cents per gallon down the street. I think that's the next step, on top of triple checking my sanitation and hitting my numbers.
Appreciate the feedback!
 
All things point to your water. I was unhappy with a few beers that I brewed, either 3 kettle or BIAB. I was always getting some weird flavor on the back of my tongue and I hated it.
After searching many threads, I narrowed it down to my water. It was too pure. I have a whole house RO water filtration system and realized that my water was void of any minerals. To figure out what my water needed, I sent my water sample to Ward Laboratories, and based on the results, I have to add Calcium Chloride, Epson Salt and Gypsum to my strike water.
Since then, I no longer get those strange flavors and I even squeeze the bag (no tannin flavors). Start there.
 
All things point to your water. I was unhappy with a few beers that I brewed, either 3 kettle or BIAB. I was always getting some weird flavor on the back of my tongue and I hated it.
After searching many threads, I narrowed it down to my water. It was too pure. I have a whole house RO water filtration system and realized that my water was void of any minerals. To figure out what my water needed, I sent my water sample to Ward Laboratories, and based on the results, I have to add Calcium Chloride, Epson Salt and Gypsum to my strike water.
Since then, I no longer get those strange flavors and I even squeeze the bag (no tannin flavors). Start there.
Thanks for the feedback. I am still relatively new to adjusting water chemistry, but will continue experimenting with some of the "balanced" profiles as suggested on Brewfather and Beersmith. Somewhere in the ballpark of 60 Ca, 7 Mg, 10 Na, 70 SO4, 70 Cl. Hopefully that's enough to make a difference with RO water.
 
I am not familiar with that yeast but I do make California commons (Anchor Steam). You might try letting it ferment for a longer time - my theory is that once you hit final gravity the yeast still has a lot of work to do in cleaning up things like diacetyl. I would let it "rest" 3 to 5 days after final gravity gravity is reached.
 
I am not familiar with that yeast but I do make California commons (Anchor Steam). You might try letting it ferment for a longer time - my theory is that once you hit final gravity the yeast still has a lot of work to do in cleaning up things like diacetyl. I would let it "rest" 3 to 5 days after final gravity gravity is reached.
I admittedly did transfer it to a keg very early and when I cold crashed there was a significant chill haze. That has since dissipated and the beer is clear, but there is still that "twang" that won't go away. You're right, I will try to give the yeast more time to clean up and re-absorb some of those off flavors. Patience is key.
 
Thanks for the feedback. I am still relatively new to adjusting water chemistry, but will continue experimenting with some of the "balanced" profiles as suggested on Brewfather and Beersmith. Somewhere in the ballpark of 60 Ca, 7 Mg, 10 Na, 70 SO4, 70 Cl. Hopefully that's enough to make a difference with RO water.

Make sure you sparge with RO water as well (no adjustments needed). Often the water for mashing is great, but then someone may use tap water for sparging. Don't worry about the additions as much as a good mash pH of 5.3 or so. The flavor ions you listed are just that- for flavor. Think of those additions like salt (well, they ARE salts) for your food. A little salt and pepper makes a good dish great, but can't make a bad dish good. Same with brewing salts- you can take a very good beer to great perhaps, but can't improve a bad beer to great just with salts. What you can do is ensure that your mash pH and sparge pH are in range, which DOES make a huge difference!
 
I admittedly did transfer it to a keg very early and when I cold crashed there was a significant chill haze. That has since dissipated and the beer is clear, but there is still that "twang" that won't go away. You're right, I will try to give the yeast more time to clean up and re-absorb some of those off flavors. Patience is key.

No, the yeast doesn't clean up off flavors much beyond about 24 hours after FG is reached. Chill haze won't impact the flavor (although it does impact colloidal stability), and a well made beer doesn't need ages and ages to taste great.
 
Make sure you sparge with RO water as well (no adjustments needed). Often the water for mashing is great, but then someone may use tap water for sparging. Don't worry about the additions as much as a good mash pH of 5.3 or so. The flavor ions you listed are just that- for flavor. Think of those additions like salt (well, they ARE salts) for your food. A little salt and pepper makes a good dish great, but can't make a bad dish good. Same with brewing salts- you can take a very good beer to great perhaps, but can't improve a bad beer to great just with salts. What you can do is ensure that your mash pH and sparge pH are in range, which DOES make a huge difference!
That's a good point. I noticed when experimenting with my water adjustments in Brewfather that adding Calcium Chloride or Gypsum to the mash does not significantly lower the pH, but when adding 20ml of 10% phosphoric acid, the pH value drops by 0.24. That should in theory stabilize the mash for this particular recipe with RO water at 5.32. Let's hope it works out like that when I calibrate my pH meter.
 
No, the yeast doesn't clean up off flavors much beyond about 24 hours after FG is reached. Chill haze won't impact the flavor (although it does impact colloidal stability), and a well made beer doesn't need ages and ages to taste great.
What does a typical Ale fermentation schedule look like for you when starting with an OG of 1.046 and FG of 1.009? Fermenting between 59-68 degrees F. In my experience, FG for ales is typically reached by day 5 or 6. Rack to secondary or leave it? I'm not sure if leaving the beer on that yeast cake will pick up any harsh flavors from dying yeast cells.
 
Last edited:
I've been brewing all-grain BIAB for about a year now, and I've been getting this harsh (possibly astringent) off-flavor in my beers post fermentation. I assume it's chlorophenols from the chlorine/chloramine reacting with the yeast, but I've treated the batches with Campden tablets and even phosphoric acid %10 (about 30ml per 3 gallon batch). I also added salts, such as CaCl, Gypsum and Epsom to the mash based on a "balanced" profile in Beersmith. This last batch was an Anchor Steam clone with a basic grain bill of 5.6 lbs 2-row, 8 oz C-40 and 8 oz of C-60. I used Mangrove Jack's m54 and pitched the yeast at 70 degrees and fermented it between 65 and 68 degrees in my temperature controlled mini fridge.

I've tried using distilled water and spring water, and I believe the spring water yielded my best batch. However, I am confused as to why the Campden tablets are not working if the flavor is in fact chlorophenols. Also, if I'm hitting a pH reading between 5.2-5.5, where is this astringency coming from?

I am stumped. Please let me know where I'm going wrong.

One other thing on your equipment: do you use a plate chiller?
 
One other thing on your equipment: do you use a plate chiller?
I use a copper IC that I put in the boil about 10-15 minutes before chilling.

I am on day 3 of fermenting my spotted cow clone with Safale K-97 at 61 F, and it is chugging along, burping up tons of CO2. I sanitized everything and even switched out my brew bag and fermenter, as I'm using a 5 gal Corny keg to ferment in now. I used my tap water treated with campden again just to see if my gear was the potential source of the off flavor.

I added my usual minerals for the desired flavor profile, but did not add phosphoric acid this time and did not bother using my pH meter because it wouldn't calibrate correctly. I suspect the pH was high, probably around 5.6/7, and that I might regret that decision, but I just want to see if this less complicated method yields good results.
 
Follow up - My flavor has improved dramatically. Here's what I changed:

1. Started fermenting in stainless corny kegs and only use "closed" CO2 pressure transfers to move wort from primary fermenter to serving keg.
2. Got the Brew Bag, which has very fine mesh and does not allow for grain particulate to build up in the seams.
3. Don't bother using my PH meter, even though I just bought a brand new one - and just add recommended dosage of 10% phosphoric acid based on Brewfather/Beersmith.
4. Use my tap water, but with campden tablets to eliminate chlorine/chloromine.
5. Allow ample time for yeast to complete fermentation. Cold crash and give time for flavors to mature. I use kveik yeast now, so my impatience is mitigated by a faster ferment with kveik.
6. Only gently squeeze the bag, and do not wring out every last ounce of wort. Rather, I just rinse it with some 170 F water.
7. Thoroughly sanitize as always.

I believe the significant improvement in my flavor came by fermenting with very minimal oxygen in the stainless corny keg. That bitter off-flavor still might be slightly present, but I cannot detect it nearly as much as my previous batches. Something must have been getting contaminated from transferring with an auto-siphon or getting oxidized. Either way, both siphoning and transferring are done with CO2 now, so the beers are tasting mighty fresh!
 
Last edited:
I had a similar harsh off flavor. I am fairly certain it was an infection of some sort. It only completely went away after replacing my keg lines with new EVABarrier lines. Somehow it was in the original vinyl lines and managed to infect each keg. At least in theory.
 
I had a similar harsh off flavor. I am fairly certain it was an infection of some sort. It only completely went away after replacing my keg lines with new EVABarrier lines. Somehow it was in the original vinyl lines and managed to infect each keg. At least in theory.
Wow! I had no idea that vinyl tubing could degrade like that. I just watched the Kegland video on EPABarrier lines and I'm already placing an order to replace my lines. Thanks for the tip!
 
Try giving the next few batches enough time to complete the ferment before you keg, then give it time to mature a bit before you chill it. You still have suspended yeast which is evidenced by the cloudiness and that doesn't have the most pleasant taste.

Leave the beer in the fermenter until at least day 10. From day 5 to day 10 let the beer be at room temp. That helps the yeast clean up the last of the fermentable sugars and do the cleanup of intermediate products. Keg it on day 10 or later, then leave the keg at room temp for another 3 to 5 days before chilling it. Give the beer 48 hours of chilling before the first pour. The taste you are getting has nothing to do with BIAB nor the fine crush.

This is what I'd put my money on. I routinely let an ale sit in the primary for 4 weeks at room temperature, (lagers usually at least 3 weeks in primary for fermentation & diacetyl rest, then rack to secondary for at least 4 weeks at lagering temp) and then let bottle condition for another 4 weeks. Takes patience! But, I think it's one reason my beer is almost always decent in spite of all the other mistakes I make :cool:
 
This is what I'd put my money on. I routinely let an ale sit in the primary for 4 weeks at room temperature, (lagers usually at least 3 weeks in primary for fermentation & diacetyl rest, then rack to secondary for at least 4 weeks at lagering temp) and then let bottle condition for another 4 weeks. Takes patience! But, I think it's one reason my beer is almost always decent in spite of all the other mistakes I make :cool:

this is ABSOLUTELY horrible advice and practice. All yeasts have different attenuation times and temperatures. Leave an ale fermented with Voss Kveik for four weeks and you are 100% wasting time. Let a dry hopped ale sit for four weeks and you’ve wasted your dry hopping.

I get it, you think your beer is excellent because of time...but it’s not always necessary, nor recommended.

i have personally consumed a kveik ale 48 hours after brewing and it was absolutely exceptional!!
That said, more often than not secondaries are not only a waste on the homebrew scale, but a recipe for infectious disaster for those with subpar sanitation skills.
All that said, cloudiness doesn’t always suggest yeast that needs to fall out of suspension. Fatty acid levels increase based on a lot of different factors, and they will all cause cloudiness. I’d be easy in telling anyone they need to let their brew “mature” in a glass fermenter before legging or bottling.

just sayin
 
BiaB has nothing to do with it man.
And I was just at a local brewery today. No flirtation. City water. No chemicals.
Blonde
Prohibition porter
3 different IPAs
Hefe
Stout
Dunkel
3 different wheats
Czech pils
Blackberry sour
2 different lagers
The IPAs need work but everything is on point and they don’t mind pH. I’m good friends with the owner and the head brewer and they just don’t care about it.

Its not obvious.

The issue isn’t pH

Assuming your sensory skills are not lacking (which we cant rule out completely), the only explanation is that their source water is down the middle in all ways such that pH is only marginally off on the light and dark extremes. This isnt really debatable.

My source water has such high alkalinity that even a RIS isnt acid enough to make a drinkable beer. A friend of mine has tap water with a TDS over 700. Blanket statements like "pH doesnt matter" are both false and unhelpful for people chasing problems. Its not always a problem, but it sometimes is.
 
this is ABSOLUTELY horrible advice and practice. All yeasts have different attenuation times and temperatures. Leave an ale fermented with Voss Kveik for four weeks and you are 100% wasting time. Let a dry hopped ale sit for four weeks and you’ve wasted your dry hopping.

I get it, you think your beer is excellent because of time...but it’s not always necessary, nor recommended.

i have personally consumed a kveik ale 48 hours after brewing and it was absolutely exceptional!!
That said, more often than not secondaries are not only a waste on the homebrew scale, but a recipe for infectious disaster for those with subpar sanitation skills.
All that said, cloudiness doesn’t always suggest yeast that needs to fall out of suspension. Fatty acid levels increase based on a lot of different factors, and they will all cause cloudiness. I’d be easy in telling anyone they need to let their brew “mature” in a glass fermenter before legging or bottling.

just sayin
Well ... to be clear ...
1. I have not ever used kviek;
2. I would never dry hop for four weeks ... that would be stupid, and I assure you I am not;
3. I don't think I said anything about cloudiness; and
4. wouldn't you agree that time and patience are important home brewing "ingredients?" I'd venture to guess that taking my time has not hurt any of my beers, even if in some cases it might not have helped.

Fwiw, it looks like we pretty much agree on secondaries.
 
Back
Top