Correcting for over sparging

[cscade]

On my last few batches, as I have progressively dialed my system in, I have started to have a problem with too high of efficiency into the kettle, as a side effect of very good rinsing.

High efficiency is not generally considered a problem, but in my case it's just a bit too high and is causing extraction issues with undesirable compounds.

My typical efficiency into the kettle is now up around 92-98% (as calculated by BeerTools), depending on the grist. Mash pH varies depending on grist, but I stay between 5.4 and 5.6 at mash temp, correcting with 88% lactic acid. I fly sparge, to kettle volume. Sparge water is acidified to pH 6-6.5. Run-off rate is very carefully monitored at 5 min/gal for the entire sparge.

I have started to notice tannin extraction, and it's hurting my beers. On the batches with the problem, final runnings have been well into the danger zone, at 1.004-1.005, with a pH of 5.7-6. I had thought I could get away with it by keeping my pH under 7, but the beers prove otherwise.

I'd like to correct for the over-sparging, but I'm not sure how best to approach changing the process without a ton of trial and error. The way I see it I could do either of;

1. Speed up the sparge
2. Stop sparging early and top off pre-boil

With either method, I don't really know how to pre-calculate the effect, and come up with a recipe that won't be terribly off.

Has anyone dealt with this, and come up with a simple correction?

 

[divrguy]

On my last few batches, as I have progressively dialed my system in, I have started to have a problem with too high of efficiency into the kettle, as a side effect of very good rinsing.

High efficiency is not generally considered a problem, but in my case it's just a bit too high and is causing extraction issues with undesirable compounds.

My typical efficiency into the kettle is now up around 92-98% (as calculated by BeerTools), depending on the grist. Mash pH varies depending on grist, but I stay between 5.4 and 5.6 at mash temp, correcting with 88% lactic acid. I fly sparge, to kettle volume. Sparge water is acidified to pH 6-6.5. Run-off rate is very carefully monitored at 5 min/gal for the entire sparge.

I have started to notice tannin extraction, and it's hurting my beers. On the batches with the problem, final runnings have been well into the danger zone, at 1.004-1.005, with a pH of 5.7-6. I had thought I could get away with it by keeping my pH under 7, but the beers prove otherwise.

I'd like to correct for the over-sparging, but I'm not sure how best to approach changing the process without a ton of trial and error. The way I see it I could do either of;


[*]Speed up the sparge
[*]Stop sparging early and top off pre-boil


With either method, I don't really know how to pre-calculate the effect, and come up with a recipe that won't be terribly off.

Has anyone dealt with this, and come up with a simple correction?

From winning homebrew site.

There are many causes of process-related astringency: over-sparging, sparging with water above 168°F (76°C), steeping your grains too long, mash pH above the 5.2-5.6 range, over hopping, or boiling your grains can extract excessive tannins from the husks. Milling your grains too fine and poor hot-break removal resulting in too much trub may be sources of astringency as well.

Seems speeding up might be my first attempt if your mash PH, temps and mill are all correct.

 

[cscade]

Sparge temperature is locked at 168F, mash rest time overall doesn't exceed 90 minutes including mash out, hot break is very good, and my crush is producing almost no flour.

I'm concerned that my pH might not be quite close enough to ideal. I have been reluctant to correct farther, just because of the amount of acid I'd have to use.

Speeding up the sparge is an easy change to make, but I'm concerned it will produce inconsistent results across batches.

 

[Yooper]

Sparge temperature is locked at 168F, mash rest time overall doesn't exceed 90 minutes including mash out, hot break is very good, and my crush is producing almost no flour.

I'm concerned that my pH might not be quite close enough to ideal. I have been reluctant to correct farther, just because of the amount of acid I'd have to use.

Speeding up the sparge is an easy change to make, but I'm concerned it will produce inconsistent results across batches.

I think it's a combination- the last runnings at too low an SG, and the pH too high.

Definitely stop the sparge by the time you get to 1.010, and top up with water if you have to- but oversparging sounds like a problem for you.

I would also say that the pH of the sparge runnings needs to be under 6. One that that really helped me is to sparge with 100% RO water. If that's not possible, you could try diluting with RO water which may help a lot. Also, consider phosphoric acid for reducing the pH (both mash and sparge) which doesn't have the flavor impact that lactic acid does.

 

[divrguy]

Sparge temperature is locked at 168F, mash rest time overall doesn't exceed 90 minutes including mash out, hot break is very good, and my crush is producing almost no flour.

I'm concerned that my pH might not be quite close enough to ideal. I have been reluctant to correct farther, just because of the amount of acid I'd have to use.

Speeding up the sparge is an easy change to make, but I'm concerned it will produce inconsistent results across batches.

All your thermometer's correct? I just found one of my mash thermometers was off 7 degrees for a while but didn't know until I had a few issues and stuck three others in there to figure it out.

 

[cscade]

All your thermometer's correct? I just found one of my mash thermometers was off 7 degrees for a while but didn't know until I had a few issues and stuck three others in there to figure it out.

Pretty sure. I have a thermapen that I use to calibrate the error on all my RTD probes, and everything seems to be accurate +/- 0.5ºF.

I think it's a combination- the last runnings at too low an SG, and the pH too high.

Definitely stop the sparge by the time you get to 1.010, and top up with water if you have to- but oversparging sounds like a problem for you.

I would also say that the pH of the sparge runnings needs to be under 6. One that that really helped me is to sparge with 100% RO water. If that's not possible, you could try diluting with RO water which may help a lot. Also, consider phosphoric acid for reducing the pH (both mash and sparge) which doesn't have the flavor impact that lactic acid does.

RO isn't in the realm of possibility unfortunately. Distilled is, but I'd prefer a different solution, because remembering to buy distilled doesn't always happen in time

Switching to a different acid is something I have been wanting to do. I have to use so much lactic to overcome my water's buffering capacity it makes me uncomfortable.

 

[Bsquared]

Have you considered using mash pH buffer? I think the simplest thing is to speed up your sparge, your efficiency will drop a bit , but if you are getting better than 80% you could afford to loose some efficiency to avoid tannins. I was under the impression that ideal sparge rate was closer to 1 liter/ min, so that would be just under 4min/ gallon.

Personally I'm to impatient for 4min/gallon, I'm closer to 2.5min/ gallon. that gets me between 75-80% extraction efficiency.

 

[Yooper]

I don't agree with using the 5.2 buffer stuff.

What I'm thinking about is that if your alkalinity is so high that you need a large quantity of acid to drop it to get an acceptable pH for your mash is sparge is that it's too much.

I bought an RO system for my house ($120) because that was my issue.

If that's not possible, I'd consider looking at the water report and then doing something to reduce the alkalinity. Maybe lime softening (which I tried). It's not that bad to do, and it might work well depending on your water chemistry.

Otherwise, preboiling to decarbonate the water and then racking off the precipitates is something that would maybe work.

It really is a water issue, and without fixing the water issue I don't think the flavor issue will go away even if the efficiency is reduced.

 

[nstnate]

My typical efficiency into the kettle is now up around 92-98% (as calculated by BeerTools), depending on the grist. Mash pH varies depending on grist, but I stay between 5.4 and 5.6 at mash temp, correcting with 88% lactic acid. I fly sparge, to kettle volume. Sparge water is acidified to pH 6-6.5. Run-off rate is very carefully monitored at 5 min/gal for the entire sparge. [/QUOTE]

Isn't 5.4 - 5.6 a little high for at mash temp? Wouldnt that be roughly 5.7-5.9 at room temp (where it should be measured). I second the highly alkaline water problem, I would try diluting with distilled also.

 

[cscade]

The only thing keeping me away from going RO is my goal; I have solid long term plans to open a nano, and I don't want to train myself to use techniques that won't scale beyond a homebrew size.

I have looked into large industrial RO systems to see if that will be an option down the road, and it really isn't.

Perhaps my fear of lactic is unfounded, let's get some real numbers in play here and you can tell me what you think:

Base Water:

pH			8.2
Sodium, Na		48
Potassium, K		2
Calcium, Ca		25
Magnesium, Mg		12
Total Hardness, CaCO3	113
Sulfate, SO4		72
Chloride, Cl		71
Carbonate, CO3		<1
Bicarbonate, HCO3	50
Total Alkalinity, CaCO3	41

By the numbers, my water is not overly hard - it's actually pretty good brewing water. There's nowhere near enough temporary hardness that it will precipitate out from boiling. My biggest problem for water chemistry is getting my calcium up to acceptable levels without blowing my chloride and sulfate way out of proportion to the hardness.

On an upcoming beer (see attachments to this post. Note: SRM is 3.3) I would need an estimated 4.6ml of lactic overall to bring the pH in line. This is on a batch that will yield 11 gallons into the fermentor. This seems like a lot of lactic to me. My experience has been that I typically need more like 6+ml to get the calculated results to actually happen, which means I'm driving my RA way, way into the negative. The estimate is always low. As such, I tend to refuse to add more than 4ml lactic overall on brew day, and let my pH ride high.

My pH measurements are taken ~130F, with a good calibrated meter with temp probe, not strips. So at that temp I'd assume that 5.2-5.6 would be the optimum mash pH?

My understanding is that the pH 5.2 that is always quoted as the best mash pH is measured (and adjusted) at mash temp, not at room temp. Optimum range at room temp is 5.4 - 5.8, from what I have read.

Having typed all this out, I feel like everyone will say this much lactic is no big deal, but that highly negative RA seems like a bad thing to me. Fortunately on dark beers I don't have to drive the RA negative, but it's light colored beers where I'm extracting tannins.

Note that the attached sheet shows a sparge water volume of 14 gallons - that's the volume in my HLT at the beginning of the sparge, not the amount I'm actually sparging with. I match rate and only sparge to pre-boil volume.

View attachment Hot Streak.pdf

 

[nstnate]

The only thing keeping me away from going RO is my goal; I have solid long term plans to open a nano, and I don't want to train myself to use techniques that won't scale beyond a homebrew size.

I have looked into large industrial RO systems to see if that will be an option down the road, and it really isn't.

Perhaps my fear of lactic is unfounded, let's get some real numbers in play here and you can tell me what you think:

Base Water:


pH 8.2
Sodium, Na 48
Potassium, K 2
Calcium, Ca 25
Magnesium, Mg 12
Total Hardness, CaCO3 113
Sulfate, SO4 72
Chloride, Cl 71
Carbonate, CO3 <1
Bicarbonate, HCO3 50
Total Alkalinity, CaCO3 41

By the numbers, my water is not overly hard - it's actually pretty good brewing water. There's nowhere near enough temporary hardness that it will precipitate out from boiling. My biggest problem for water chemistry is getting my calcium up to acceptable levels without blowing my chloride and sulfate way out of proportion to the hardness.

On an upcoming beer (see attachments to this post. Note: SRM is 3.3) I would need an estimated 4.6ml of lactic overall to bring the pH in line. This is on a batch that will yield 11 gallons into the fermentor. This seems like a lot of lactic to me. My experience has been that I typically need more like 6+ml to get the calculated results to actually happen, which means I'm driving my RA way, way into the negative. The estimate is always low. As such, I tend to refuse to add more than 4ml lactic overall on brew day, and let my pH ride high.

My pH measurements are taken ~130F, with a good calibrated meter with temp probe, not strips. So at that temp I'd assume that 5.2-5.6 would be the optimum mash pH?

My understanding is that the pH 5.2 that is always quoted as the best mash pH is measured (and adjusted) at mash temp, not at room temp. Optimum range at room temp is 5.4 - 5.8, from what I have read.

Having typed all this out, I feel like everyone will say this much lactic is no big deal, but that highly negative RA seems like a bad thing to me. Fortunately on dark beers I don't have to drive the RA negative, but it's light colored beers where I'm extracting tannins.

Note that the attached sheet shows a sparge water volume of 14 gallons - that's the volume in my HLT at the beginning of the sparge, not the amount I'm actually sparging with. I match rate and only sparge to pre-boil volume.

How big of boil kettle are you using? And the batch size? I have had your issue before I think.

 

[Wynne-R]

There’s a thread on Brew Science where there’s a guy that insists on measuring his hash pH hot. Here’s the money quote:

Brewers have noted that the true pH of the mash seems to increase about 0.0055 pH per degree C temperature rise. - A.J. DeLange

https://www.homebrewtalk.com/f128/ph-meter-temperature-compensation-408650/

55-25 * .0055 = .165 There’s your fudge factor. The consensus on Brew Science is that the optimal mash temp is 5.2 -5.4 at standard temperature 25C (77F). If you shoot for the middle your 130F reading should be 5.14 ± .1.

Cool your sample and see what you get. Or you could just take your measurements at room temperature like everyone else.

I agree with Yooper that you should pay attention to your sparge pH. Here’s what the BJCP says about astringency:

Don't oversparge. Don't overcrush grain. Don't boil grain. Don't sparge with water above 170°F. Don't sparge with water with a high pH (over 6). Use water with lower sulfate content. Use less dark grains (especially black malt). Use less whole hops (especially high-alpha hops or simply large quantities of hops). Avoid use of raw spices, fruit pith and fruit skins.

-http://www.bjcp.org/faults.php

 

[cscade]

20 gallon kettle, pre-boil volume is ~14.6gal (hot), post-boil is 11.5gal (hot), volume into ferment is 10.5 - 10.75gal (cold).

How big of boil kettle are you using? And the batch size? I have had your issue before I think.

 

[WestCoastBrewmonkey]

Would you describe an astringent as have a bite or somewhat bitter taste?

 

[cscade]

Drying, tannic. Like a dry wine. I've had it vary from barely detectable to highly obvious, depending on mash parameters and sparge rate.

Would you describe an astringent as have a bite or somewhat bitter taste?

 

[cscade]

Cool your sample and see what you get. Or you could just take your measurements at room temperature like everyone else.

Not to get too far off into the weeds here, but I don't know why folks like to toss around that room temperature is "right" or the way "everyone" does it. If you're talking about people who use test strips, then yes, they do it at room temp because they don't have a choice - their readings would not be valid otherwise.

But in the case of brewers who use ATC meters, like I do, there is no reason or need to cool the sample beyond what you have to do to get into the working range of the meter. My meter has a working range up to 150F, so I pull samples and cool them to ~130F before taking a reading.

55-25 * .0055 = .165 There’s your fudge factor. The consensus on Brew Science is that the optimal mash temp is 5.2 -5.4 at standard temperature 25C (77F). If you shoot for the middle your 130F reading should be 5.14 ± .1.

John Palmer did a very good talk at Northern Brewer, in which he talks about measurement of pH at various temperatures, specific to brewing. He states that when using a calibrated ATC meter, target pH at room temperature is 5.4 - 5.8. Target pH at mash temperature is 5.1 - 5.5. I keep my mash pH readings within that range.



I agree with you guys - I think my sparge pH is running too high. That said, I'm not sure if it will make any difference, so long as I adjust my sparging practices to maintain a runoff gravity of 1.010 or higher. I think my runoff gravity is the larger mole to whack at the moment.

 

[nstnate]

20 gallon kettle, pre-boil volume is ~14.6gal (hot), post-boil is 11.5gal (hot), volume into ferment is 10.5 - 10.75gal (cold).

Ok so i have had this issue, you boil off rate is very high (either do to to vigorous of boil or my issue to big of pot). Now the the beginning of the problem running to much water through the grain (oversparging), in which causes some tannin from the mash but also will cause the boil ph to be to high, in which will extract harsh tannins from the hops during the boil. So first I would try to get your pre boil down some, then try a thinner mash to cut down on sparge water. Also would acidify sparge water a little more. I also find more consistent ph #s when doing all of them at room temperature.

 

[Bsquared]

Having typed all this out, I feel like everyone will say this much lactic is no big deal, but that highly negative RA seems like a bad thing to me. Fortunately on dark beers I don't have to drive the RA negative, but it's light colored beers where I'm extracting tannins.

Lactic acid is a weak acid, so you are going to have to add quite a bit of it to get an effect. the good news about that is the flavor threshold for lactic acid is quite high ~100 to 700 mg/l depending on who is tasting.

looks like you are adding 4.6ml of 88% Lactic acid to your total beer @~14 gallons or 54.6 Liters. 4.6ml of 88% Lactic is the equivalent of 12.824g of Lactic acid 12824mg/54.6L = 234mg/l

Also, Lactic acid is also a metabolite to I'd bet te yeast are able to take some up and use it.

Have you tried raking the top third of the sparge every 15min during the sparge?

 

[cscade]

Ok so i have had this issue, you boil off rate is very high (either do to to vigorous of boil or my issue to big of pot). Now the the beginning of the problem running to much water through the grain (oversparging), in which causes some tannin from the mash but also will cause the boil ph to be to high, in which will extract harsh tannins from the hops during the boil. So first I would try to get your pre boil down some, then try a thinner mash to cut down on sparge water. Also would acidify sparge water a little more. I also find more consistent ph #s when doing all of them at room temperature.

I hadn't even considered the boil pH being too high as an issue, but that makes complete sense.

I mash at 1.5 qt/lb, which is typically as thin as I go. I have gone to 2, but saw a reduction in conversion efficiency. That was before the 3-roller mill though, so it's worth experimenting with again.

My boil may be too agressive. I can tune that down to reduce my boil-off rate.

Lactic acid is a weak acid, so you are going to have to add quite a bit of it to get an effect. the good news about that is the flavor threshold for lactic acid is quite high ~100 to 700 mg/l depending on who is tasting.

looks like you are adding 4.6ml of 88% Lactic acid to your total beer @~14 gallons or 54.6 Liters. 4.6ml of 88% Lactic is the equivalent of 12.824g of Lactic acid 12824mg/54.6L = 234mg/l

Also, Lactic acid is also a metabolite to I'd bet te yeast are able to take some up and use it.

Have you tried raking the top third of the sparge every 15min during the sparge?

Interesting numbers. That seems to suggest I could go all the way up to 13.8ml of lactic at this batch size before I started to exceed 700mg/l. That's much more than I would ever require.

I run a recirculating mash for 60 minutes, ramp for 20 minutes to mash out, and then start the sparge. I cut my mash 15 minutes after mashing in, and that's typically it. My grain bed is fully set and the wort is crystal by the time I start the sparge, so I don't mess with cutting again. I maintain water above the grain bed by ~1-2" throughout the sparge, until close to the end.

 

[Bsquared]

Do you mesure the pH of the top two inches above of the grain bed at the end of the sparge ,or just the runnings?

 

[cscade]

Just the runnings. I would expect the liquid above the grain to be pretty much pure water at that point.

Do you mesure the pH of the top two inches above of the grain bed at the end of the sparge ,or just the runnings?

 

[Bsquared]

Just the runnings. I would expect the liquid above the grain to be pretty much pure water at that point.

So that pH in the top portion of your sparge might be getting fairly high and could be the point where you are getting tanin extraction.

 

[cscade]

It's likely. I have been told by brewers I trust that I didn't need to worry about tannin extraction unless I was both below 1.008 and above pH 7, but it looks like in my case I need to be more careful. I am very sure my pH has never been over 7 (I acidify the sparge water) and I'm still having the problem.

 

[nstnate]

So that pH in the top portion of your sparge might be getting fairly high and could be the point where you are getting tanin extraction.

Wouldn't this be about the same as the sparge kettle ph? So acidify the sparge more?

 

[Bsquared]

Wouldn't this be about the same as the sparge kettle ph? So acidify the sparge more?

you would think, but the top of the grain bed, all the husks and mash material will be negatively charged and will be capturing H+ from the sparge water and freeing -OH slowly raising the pH. As the wort is removed the buffering capacity of the mash decreases. Acidification will help, but what you need more of is buffering capacity. Thats why phosphate buffers are good, or just agitating the top of the grain bed to help keep the gravity above 1.012 and maintain its buffering capacity.

at least this is the way I understand it.

 

[nstnate]

you would think, but the top of the grain bed, all the husks and mash material will be negatively charged and will be capturing H+ from the sparge water and freeing -OH slowly raising the pH. As the wort is removed the buffering capacity of the mash decreases. Acidification will help, but what you need more of is buffering capacity. Thats why phosphate buffers are good, or just agitating the top of the grain bed to help keep the gravity above 1.012 and maintain its buffering capacity.

at least this is the way I understand it.

Interesting, do you have any other info/articles or links on this subject?

 

[Bsquared]

Not really, this is just the way I understand it from my studies. I have a BS in Pharmacology/biochemistry.

I did a little googling and found this link,
http://beerdujour.com/SpargingDeMystified.htm

Im sure there is a more definitive study some where.

What are the disadvantages? Why doesn’t anyone ever talk about the disadvantages?
When the gravity of the wort drops below 1.019 (some say 1.010) tannins from the husk are extracted. In the continuous sparge process the grain at the top of the grain bed, being continuously introduced to plain hot water, becomes depleted early in the process, thus the gravity at the top of the grain bed is meeting the requirements for extraction of tannins, hot, low gravity, and elevated pH. The pH increases (especially with base/light malts) as the pH buffering ability of the malt falls off with the extraction of the sugars (the SG of the wort drops). The gravity of 1.019 (1.010) is to ensure that the extraction of tannins has not occurred enough to significantly impact the flavor of the resulting beer.

 

[cscade]

It would be easy to work around all this by simply batch sparging and calculating for a lower efficiency, but again, I need to use only techniques viable at a professional scale.

So far the most "lightbulb over my head" moment in this thread for me has been the suggestion to reduce my pre-boil volume. I do 90 minute boils, and boil fairly hard, leading to a combined need for a pretty high pre-boil volume. Dialing back the heat a touch will reduce my boil-off rate, and thereby reduce my need to sparge. Combined with more thorough acidification, we may just have a winner.

What are everyone's opinions about very negative RA for light colored beers? Palmer recommends targeting -50 for light beers, but I'll be blowing right past that, sometimes as deep as -100.

 

[Yooper]

What are everyone's opinions about very negative RA for light colored beers? Palmer recommends targeting -50 for light beers, but I'll be blowing right past that, sometimes as deep as -100.

Recently I've come to believe that RA is completely meaningless for the most part.

The important factor: pH! If your mash pH is at optimum range (5.3-5.5 at room temperature) and your sparge pH is under 6 (not 7), then the RA won't come into play at all.

 

[cscade]

I did a test brew to modify my process over the weekend, and collected a lot of data points. The beer was a summer blonde. Here's the high points;

• I reduced my boil-off rate from 1.9gph to 1.66gph by reducing the heat.
• I increased my sparge speed from 5min/gal to 3.5min/gal.
• I monitored my runoff gravity after each gallon, and stopped runoff at 1.008 SG and pH 5.8 @ 70F.
• Efficiency fell from the previously expected 92% to 80%.

I was surprised at how early I had to stop the runoff. I was only able to sparge up to 10.5 gallons (hot), and had to dilute up to my pre-boil volume of 12.75gal (hot). Final runnings were still just barely sweet, and had no hint of tannins.

I used a lot more lactic acid than ever before to get my mash pH in line. Overall, I had to use 6ml to bring my mash down to pH 5.27 @ 120F. I checked pH after every ml addition, and noticed a few interesting things. pH falls quickly with each acid addition, until enough acid has been added to counteract the buffering capacity of the water. After that, each ml seemed to have progressively less impact. For instance I started at pH 5.8 at mash-in. That fell to 5.36 after 4ml, and it took 2 more ml to drop to 5.27. All those measurements are at 120F. Because I had to adjust so much, I didn't reach pH 5.27 until 40 minutes into a 60 minute mash (add, wait, measure, repeat).

All indications are that this will be a tasty beer. I had to make way more on-the-fly decisions than a normal brew day so it was stressful, but once I dial in this new process things should become easier.

Any questions, I have lots more data.

 

[BreezyBrew]

I would love to hear how the beer turned out, I believe I may be encountering the same issue.

 

[cscade]

The beer is definitely improved. I have plenty of fine tuning to do yet to get my numbers working consistently again, but take-aways are;

• pH, pH, pH
• Reduce the vigor of your boil to reduce your evaporation, and therefore your required sparge volume. Don't go too far with this, as a weak boil imparts it's own problems, but if your boil-off rate is near 2gph for instance, your boil is probably too vigorous unless your kettle is 4' across and 6" deep.
• Really monitor the gravity coming off your sparge. For me, this required changing my sparge configuration from bottom-up to a hose hanging into the top of my boil kettle.

The beers I have made on this new process are definitely lacking the grainy problem.

Cheers!

 

[BreezyBrew]

So I did an experiment to try and eliminate water as the culprit for the taste.

I boiled to solutions of hops and water. The first, I made with the exact same water profile that I brew with. The second was 100% RO water. I boiled them for 60 minutes. After tasting both, they were very bitter (probably could have gone easier with the hops) but neither have that lingering "sour" flavor that only shows up a few minutes after tasting the beer.

I do use Bru'n water and my est PH of my brews is usually about 5.4. I haven't tested anything yet with equipment, that will probably be one of my next upgrades. My more recent brews I have FWH'ed so may be that's a cause of it too. This most recent brew, I took my mash water up to 2.0 qt/gal and also acidified my sparge water (which I usually do) but it happened to be a lot less. I did taste the wort when I took the OG reading, and it seemed to have the flavor. Now I am wondering what the wort would taste like "pre hopped". Really there's only two things left that come to mind about this flavor... process and possible contamination.

 

[PissyFingers]

can i ask what your water/grist ratio is in your mash?

 

[cscade]

I definitely recommend tasting everything at every step of the process. Taste all your grains individually before milling (except maybe black patent ). Taste your first runnings. Taste your final runnings. Taste the mixed wort prior to the first hops going in. Taste what goes into the fermenter. Taste it all! It's not going to taste like beer before the yeast does it's thing, but you will be able to identify if a flavor suddenly appears after step X.

I also use Bru'n water, and for my water it's pH estimates are always wrong. It's in what you could consider the ballpark I guess - typically within 0.2 pH - but for the mash that just isn't close enough. Don't get me wrong, it's a good tool, but if you want to know your mash pH, no spreadsheet is ever going to be able to tell you.

If the flavor you're experiencing is the same as mine, I'd say hops are certainly not the culprit. Although difficult to describe, there's no doubt the flavor in question is grain derived.

 

[BreezyBrew]

can i ask what your water/grist ratio is in your mash?

I've done 1.25, 1.5, and 2, and it doesn't seem to matter. Although, the 2.0 mash the verdict is still out, I don't have high hopes for the post fermentation taste to change much. I also do acidify my sparge water.

Great advice about tasting everything, had I thought about it before my last brew session... might have been able to pinpoint. Except for the black patent ;-) Adicifying my mash water I would try to get the pH as reasonably low as I could. Without having the hardness go into the negative range.

I also use lactic so I'm wondering if this and the grain mixture have something to do with it. I think I'm going to order some phosphoric since I've read that doesn't change the taste much. I've also thought about using 2% acid malt a twirl.

Thanks for the suggestions, and I'm open to any additional.

 

[cscade]

This reference - Lactate Taste Threshold Experiment - posted by Bsquared earlier in this thread, removed any fears I may have had about using lactic. So for me, I decided not to switch to a less forgiving acid.

I've not noticed mash thickness being an issue either. I run in the 1.5-1.75 qt/lb range typically. I have gone much higher on small BIAB batches and had no issues whatsoever. The pH really seems to come into play on this particular problem in the sparging step only - BIAB doesn't have one.

 

[BreezyBrew]

I realized that the aftertaste I'm experiencing is very similar to the after taste of yogurt. It's sour, milky tasting and long lasting. Palmer is quoted as saying the threshold is about 2ml/gallon, and some of my beers have been in the ballpark of that range. After doing some research on the last 5 beers I have produced, the one that relied least on lactic (had some darker grains) had the least amount of the lactic flavor.

I'm not trivalizing the study that was presented, because it's much more scientific then I would ever be, but it seems as though I need to run my own experiment. It doesn't seem terribly difficult to put some small increasing amounts of it in a flavor neutral beer and compare it to a control. By now I've got a pretty good handle on what I'm tasting.

I'm beginning to wonder if there are a couple of causes here... Water additions as well as astringency issues. The good news is that I purchased a pH meter with all the necessary solutions and it will be ready for the next time I brew. Also, it has crossed my mind that I haven't been converting the ml to tsp correctly, or accurately measuring them so purchasing a syringe is a good idea for me.

If these experiments don't pinpoint a cause, looks like I'll need to make room for some stout in my fermenter