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Ways To Lower S-04 Acidity?

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Resurrecting an old thread, but dry hopping increases pH. Without taking this into account, dry hopped beers are often lackluster. Maybe the lower pH from S-04 and the higher pH dry hopping are the perfect match?
Dryhopped beer are lack luster? What? What beers have you had that dryhoping made it lack luster?
 
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I think the s04 that is sold nowadays doesn't have this acidic thing going on anymore. Don't know what changed but it's almost like it's a different yeast.
I have recently had two beers made by a friend of mine with SO4 that were really good with nice fruity english yeast profile.
 
I think the s04 that is sold nowadays doesn't have this acidic thing going on anymore. Don't know what changed but it's almost like it's a different yeast.

Unfortunately I have to disagree. I just brewed a 1.037 dark mild (Maris Otter & flaked oats with small amounts of crystal 45 & 77 and Carafa Special I only in the vorlauf when mashing out, and invert #3 in the boil). I mashed at 152F/67C.

My Tilt was showing that the beer had dropped to 1.016 after 4 days and I decided to take a sample to test with a hydrometer and confirm. And of course I tasted the sample after. Weird twang/tartness. What temp did I ferment at, you ask? Pitched a fresh sachet of S04 (sprinkled on top) at 64F/18C and it rose to 66F/19C and then has dropped back to 64F/18C. Which is the very low end of what they recommend.

I found this thread because I was searching to see if anyone had successfully used baking soda to neutralize the tartness. This AHA forum thread seems to suggest that adding baking soda or chalk to an overly acidic finished beer can work, so I'll have to try it and report back:
Pinch of Baking Soda to reduce acid
 
Unfortunately I have to disagree. I just brewed a 1.037 dark mild (Maris Otter & flaked oats with small amounts of crystal 45 & 77 and Carafa Special I only in the vorlauf when mashing out, and invert #3 in the boil). I mashed at 152F/67C.

My Tilt was showing that the beer had dropped to 1.016 after 4 days and I decided to take a sample to test with a hydrometer and confirm. And of course I tasted the sample after. Weird twang/tartness. What temp did I ferment at, you ask? Pitched a fresh sachet of S04 (sprinkled on top) at 64F/18C and it rose to 66F/19C and then has dropped back to 64F/18C. Which is the very low end of what they recommend.

I found this thread because I was searching to see if anyone had successfully used baking soda to neutralize the tartness. This AHA forum thread seems to suggest that adding baking soda or chalk to an overly acidic finished beer can work, so I'll have to try it and report back:
Pinch of Baking Soda to reduce acid
Don't judge it just because of the sample from the fermenter. This can lead you into the completely wrong direction. I am drinking a s04 blonde bitter at the moment which also had this twang when bottling. At least I tasted it at that time. Don't know, but after carbing and three weeks in the bottle, no twang at all. I cannot tell if I tasted something which wasn't there or if it's gone now. Process wise, I made a starter with about 3g of yeast to remove the drying shock and this beer is remarkably clean and fresh tasting.
 
I also just brewed 2 beers with S-04 for the first time in years. Both cleared significantly on the third day. Both tasted downright sour a few days later, when I am accustomed to (normal) highly flocculant English yeast being done. Both lost the sourness, along with about one gravity point, over the following week, and then tasted fine. Both were fermented up to about 71 degrees and still had a little pleasant fruitiness after the sourness cleared up. Drinkable at 10-14 days, where I am used to putting an A-09 beer into a cask around day 7-8.

Seems strange, but it played out the same way twice in a row. The second batch was pitched with slurry from the first--zero lad (as opposed to over 12 hours) but otherwise tasted the same. Maybe the S-04 wants to be roused when it starts to floc out or something--I don't know. Maybe that's just how it behaves. Attenuation was 67% for the one mashed really high and 79% for the one mashed really low, which seems normal.

I will say that although both beers were delicious, I keep feeling like maybe I'm still tasting a tang sometimes. If it's real, it's very faint. My brain might be playing tricks on me. I can't tell.

Edited: A few weeks later I decided the subtle tartness was real.
 
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I also just brewed 2 beers with S-04 for the first time in years. Both cleared significantly on the third day. Both tasted downright sour a few days later, when I am accustomed to (normal) highly flocculant English yeast being done. Both lost the sourness, along with about one gravity point, over the following week, and then tasted fine. Both were fermented up to about 71 degrees and still had a little pleasant fruitiness after the sourness cleared up. Drinkable at 10-14 days, where I am used to putting an A-09 beer into a cask around day 7-8.

Seems strange, but it played out the same way twice in a row. The second batch was pitched with slurry from the first--zero lad (as opposed to over 12 hours) but otherwise tasted the same. Maybe the S-04 wants to be roused when it starts to floc out or something--I don't know. Maybe that's just how it behaves. Attenuation was 67% for the one mashed really high and 79% for the one mashed really low, which seems normal.

I will say that although both beers were delicious, I keep feeling like maybe I'm still tasting a tang sometimes. If it's real, it's very faint. My brain might be playing tricks on me. I can't tell.
Good to know that there is a chance the twang will go away.

Tilt says I am at 57% attenuation after 4 days. The sample I pulled was very clear. I do fear that the yeast has already flocced out, but I know I should let it do its thing.

Some threads say to ferment this yeast cool to prevent the twang. Others say that fermenting cool will cause the yeast to flocculate and underattenuate. My life is complicated enough. I don't think I need to bother with this yeast again!
 
Unfortunately I have to disagree. I just brewed a 1.037 dark mild (Maris Otter & flaked oats with small amounts of crystal 45 & 77 and Carafa Special I only in the vorlauf when mashing out, and invert #3 in the boil). I mashed at 152F/67C.

My Tilt was showing that the beer had dropped to 1.016 after 4 days and I decided to take a sample to test with a hydrometer and confirm. And of course I tasted the sample after. Weird twang/tartness. What temp did I ferment at, you ask? Pitched a fresh sachet of S04 (sprinkled on top) at 64F/18C and it rose to 66F/19C and then has dropped back to 64F/18C. Which is the very low end of what they recommend.

I found this thread because I was searching to see if anyone had successfully used baking soda to neutralize the tartness. This AHA forum thread seems to suggest that adding baking soda or chalk to an overly acidic finished beer can work, so I'll have to try it and report back:
Pinch of Baking Soda to reduce acid
This isn’t necessarily directed at you per se but for everyone. We can’t make claims about a specific yeast strain having a greater ph drop in fermentation (increasing acidity) without an accurate ph reading. There are many things that can cause off flavors that can be described as a twang.
 
Good to know that there is a chance the twang will go away.

Tilt says I am at 57% attenuation after 4 days. The sample I pulled was very clear. I do fear that the yeast has already flocced out, but I know I should let it do its thing.

Some threads say to ferment this yeast cool to prevent the twang. Others say that fermenting cool will cause the yeast to flocculate and underattenuate. My life is complicated enough. I don't think I need to bother with this yeast again!
Honestly, in my opinion s04 is one of the easiest yeasts to work with, as long as one doesn't try too hard to work with it, if this makes sense.

Just use enough healthy yeast and leave it at about 20c for at least seven days, bottle, that would be it.
 
This isn’t necessarily directed at you per se but for everyone. We can’t make claims about a specific yeast strain having a greater ph drop in fermentation (increasing acidity) without an accurate ph reading. There are many things that can cause off flavors that can be described as a twang.
It would be really interesting to see if the ph changes from "tasting tart from the fermenter" to "tasting normal after few weeks in the bottle".
 
I've never picked up on this with S-04 so I'll have to see if I can be mindful the next time I brew with it. I happen to like it and haven't had any issues with it. Made a killer English Bitter with it a couple winters ago and compared it with Imperial's A09 Pub and really couldn't pick out a difference.
 
I've seen a lot of talk about how clean (the current incarnation of) s-04 is, but I tasted one of my recent beers along with an old bottle of a previous version of the same ale fermented with A-09 and found them surprisingly similar, although noticeably different.

The A-09 was fruitier overall, sweeter, with a definite orange flavor not found in the s-04 ale. But the two I just did with s-04 at 71F (closer to 22C) were quite estery with a pleasant English character. It's giving me what I want for what I am brewing, which is great since it's cheap and easy to work with (relatively fast, fairly attenuative, repeatable, flocculant, can survive shipping in the sunny South, etc). I do plan to try fermenting one cooler just to see what the yeast can do though.
 
Does anyone actually measure the final beer pH when referring to the “twang”. English yeast can be notorious for dropping pH significantly. Finished beer pH in the low 4s can definitely taste a bit acidic or twangy.

I know making a starter with dry yeast is technically wrong but from my experience with this yeast this can actually help prevent this yeast in particular from driving pH way down during fermentation and eliminating the “twang”.

Otherwise make sure the pH of your knock out wort is a bit higher, this can help final beer pH finish a touch higher.

And if you don’t have a pH meter, you should. It’s the best investment you’ll ever make. Brewing beer without a pH meter is like driving a car without a speedometer.
 
Here is another HBT thread about S-04 twang: Let's talk S-04 and tartness

Some quotes:

There is a small tartness that I've noticed from it when fermenting above 64-65 degrees.

When I first used S-04 in a brown ale, before I had ferm temp control, it just about made me vomit.
Tried it in a brown ale again at ~68F with some rudimentary control, still hated that sour apple twang it gave me.
Got good temp control and tried it again at 65F and it was almost palatable.
Tried it again at 63F and BINGO, totally different (and very enjoyable!) beast.

That's the key - the Whitbread B family tend to produce lactic acid when they're fermented warm.

Weirdly, Lallemand says the correct range for S-04 is 18-26°C (64.4-78.8°F)! I fermented at 64-66 (according to the Tilt, which seems to measure temps very well).

I don't have a pH meter and I'm not really interested in getting one. I trust Bru'n water for my mash pH calculations. But in this case, I wish I had one. Seems like a good Brulosophy experiment.
 
So4 makes pretty nice ciders! Not bone dry like wine yeast, but still dry. I think one of my ciders finished at 1.004 with s04, or thereabouts, and one at 1.008.

I've used it at 62F in ales, and thought it was pretty clean, but over that and it got tart with some esters (because it's an English strain I assumed).
 
It would be really interesting to see if the ph changes from "tasting tart from the fermenter" to "tasting normal after few weeks in the bottle".
I would assume the ph would stay the same or even drop due to bottle conditioning and increased floccuatuon
 
I wonder if the tart thing is only noticeable in certain beer styles. I've been using S04 for my imperial stout for nearly two decades now and have never thought of "tart" as a character in it...

Cheers!
Sounds to me like folks are experiencing acetaldehyde because they aren’t raising temp at the end of fermentation and giving the beer a chance to clean its self up. For those unfamiliar, it’s a precursor to ethanol and taste like Granny Smith apples or cider. Which would be a twangy tart character in the beer
 
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Sounds to me like folks are experiencing acetaldehyde because they are raising temp at the end and give the beer a chance to clean its self up. For those unfamiliar it’s a precursor to ethanol and taste like Granny Smith apples or cider. Which would be a twangy tart character in the beer
This is what my yeast microbiologist friend told me last night in our weekly homebrew club zoom meeting. Reading through other threads (there is a LOT written about this yeast) S04 can drop out and not finish the job cleaning up acetaldehyde (or take a long time doing it). This 1.037 beer has been sitting at 1.015 for two days. I have a half packet of Notty in the fridge. I think I’ll make a small starter and kräusen the beer this weekend and transfer it into a keg and let it clean up and naturally carbonate. This is my standard procedure with lagers anyway.

I also noticed that they changed the recommended temperature range for this yeast. It used to be 59-68.
 
This is what my yeast microbiologist friend told me last night in our weekly homebrew club zoom meeting. Reading through other threads (there is a LOT written about this yeast) S04 can drop out and not finish the job cleaning up acetaldehyde (or take a long time doing it). This 1.037 beer has been sitting at 1.015 for two days. I have a half packet of Notty in the fridge. I think I’ll make a small starter and kräusen the beer this weekend and transfer it into a keg and let it clean up and naturally carbonate. This is my standard procedure with lagers anyway.

I also noticed that they changed the recommended temperature range for this yeast. It used to be 59-68.

Did it work?
 
Did it work?
Something worked! I did pitch a very active Nottingham starter into a keg and transferred the beer on to it with maybe 10g of whole leaf Worcester Goldings dry hop. It cleaned up the weird flavor and the beer ended up coming in 2nd in our club mild competition. The winner had a very similar recipe but used Imperial Pub yeast and his beer was just plain on target. Going to have to try that yeast next time. I’m done with S04. The beer did drop crystal clear, but looks aren’t everything.
 
Something worked! I did pitch a very active Nottingham starter into a keg and transferred the beer on to it with maybe 10g of whole leaf Worcester Goldings dry hop. It cleaned up the weird flavor and the beer ended up coming in 2nd in our club mild competition. The winner had a very similar recipe but used Imperial Pub yeast and his beer was just plain on target. Going to have to try that yeast next time. I’m done with S04. The beer did drop crystal clear, but looks aren’t everything.
Losing against pub is like losing against Kasparov in playing chess.

S04 is a great yeast! ... At the end you've won against everyone else, except pub.
 
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Losing against pub is like losing against Kasparov in playing chess.

S04 is a great yeast! ... At the end you've one against everyone else, except pub.
The worst part was that my beer was the first one being judged, which is usually the kiss of death. But after tasting the pub version I knew it didn’t matter what the judging order was. We had 8 solid entries in our competition and it was a fun night.
 
I have been running a few experiments. Too many people report opposite performance from this yeast to write it off. There must be a process difference responsible for the tang, and we should be able to figure it out.

Earlier in the thread I reported 2 sequential brews that were good, but I kept thinking I was tasting a little sourness. I finally decided that both of them had the same tart off-flavor. Today I am starting to drink the first of 2 sequential brews that absolutely do not have the same tart off-flavor. However, it should be noted that they both did before fermentation was complete (I have a theory about this). The tangy brews were both pale and shared the same water treatment. The good brews were both very dark and shared a different water treatment scheme. This morning I put a third (from the same slurry) in the fermenter that is pale--it will (hopefully) determine whether the tart off-flavor is an artifact of the water chemistry alone.

I do not own a pH meter. I brew with well water that has 35ppm alkalinity and single-digit ppm of everything else and I use the Bru'ngard spreadsheet. I treat 12 gallons of water the night before and add no other minerals or acid during the brewday. I BIAB, start with a thick mash, and do a couple of infusions to get to full volume. I control fermentability by time spent at 145 and 158. Prior to the change I made for the recent good S04 beers, I was adding gypsom and calcium chloride to get calcium up to about 120ppm. I made a bunch of good English ales this way using Imperial Pub A-09 and WY1469. But what I noticed was that, while I could put the mash at any pH I wanted (per the model), the spreadsheet showed the pH of my final full volume of wort dropping to very low numbers. But I was making good beer until I tried S-04.

All that said, for the good S-04 brews, I used much softer water--soft enough to get the spreadsheet model to predict a pH of 5.5-5.6 for the full volume mash (total calcium=50-75). With a pale beer, this resulted in a pH prediction for the starting thick mash of way high. I don't have acid or a pH meter, so I added black patent to get it down to 5.4-5.5, and made a dark brown ale that is as good as anything I have brewed. I dry pitched 2 packs of S-04 into 6 gallons of 1.046 wort. The second brew (with 1/4 of the slurry) was a Guinness clone, in which I added a little baking soda to the mash (not the liquor) to get the predicted pH up to 5.4-5.5 for the starting thick mash. Bru'nwater predicted the full volume pH at 5.5-5.6.

My theory: there is an off-flavor produced by S-04 during fermentation that is either: 1. NOT produced when the wort pH is above some threshold, 2. is only cleaned up when the wort pH is above some threshold (my current favorite), or 3. not detectable when the wort pH is above some threshold AND/OR dark roasted grain is present in sufficient quantities.

I think #1 is not correct because I taste my beer a lot throughout fermentation and I tasted the flavor on both good beers before they were done. I think #3 is not correct for the same reason. Note that this is not simply acetaldehyde. I am very sensitive to it and have used its disappearance as a cue to cask in the past with consistent results. It might be acetaldehyde plus some other factor though.

As for how S-04 seems to work, I think it wants to attenuate about 73-78%, depending on wort composition, works though simple sugars in 2 days, but takes another 3-5 to drop the last few gravity points and clean up. Between 65 and 70 it leaves a soft sweetness, warm bread, and generic light fruit in the background, with no fusels or twang, assuming wort pH is on the high side. If wort pH is on the low side, it reliably leaves a raw biscuit dough sourness that is universally unpleasant. These are my results--actual temperature range might be a little broader.

I hope some other brewers (with pH meters) look into this further. If my recent findings hold, S-04, when used within certain easy-to-maintain parameters, might be the answer to the age old question "is there a decent English dry yeast?" As for me, I am out of S-04 packets. I am going to try the Nottingham/Windsor combo in the next few brews. But these 2 (maybe 3) beers are good enough that I will use S-04 in the future, despite almost swearing it off for good.
 
I have been running a few experiments. Too many people report opposite performance from this yeast to write it off. There must be a process difference responsible for the tang, and we should be able to figure it out.

Earlier in the thread I reported 2 sequential brews that were good, but I kept thinking I was tasting a little sourness. I finally decided that both of them had the same tart off-flavor. Today I am starting to drink the first of 2 sequential brews that absolutely do not have the same tart off-flavor. However, it should be noted that they both did before fermentation was complete (I have a theory about this). The tangy brews were both pale and shared the same water treatment. The good brews were both very dark and shared a different water treatment scheme. This morning I put a third (from the same slurry) in the fermenter that is pale--it will (hopefully) determine whether the tart off-flavor is an artifact of the water chemistry alone.

I do not own a pH meter. I brew with well water that has 35ppm alkalinity and single-digit ppm of everything else and I use the Bru'ngard spreadsheet. I treat 12 gallons of water the night before and add no other minerals or acid during the brewday. I BIAB, start with a thick mash, and do a couple of infusions to get to full volume. I control fermentability by time spent at 145 and 158. Prior to the change I made for the recent good S04 beers, I was adding gypsom and calcium chloride to get calcium up to about 120ppm. I made a bunch of good English ales this way using Imperial Pub A-09 and WY1469. But what I noticed was that, while I could put the mash at any pH I wanted (per the model), the spreadsheet showed the pH of my final full volume of wort dropping to very low numbers. But I was making good beer until I tried S-04.

All that said, for the good S-04 brews, I used much softer water--soft enough to get the spreadsheet model to predict a pH of 5.5-5.6 for the full volume mash (total calcium=50-75). With a pale beer, this resulted in a pH prediction for the starting thick mash of way high. I don't have acid or a pH meter, so I added black patent to get it down to 5.4-5.5, and made a dark brown ale that is as good as anything I have brewed. I dry pitched 2 packs of S-04 into 6 gallons of 1.046 wort. The second brew (with 1/4 of the slurry) was a Guinness clone, in which I added a little baking soda to the mash (not the liquor) to get the predicted pH up to 5.4-5.5 for the starting thick mash. Bru'nwater predicted the full volume pH at 5.5-5.6.

My theory: there is an off-flavor produced by S-04 during fermentation that is either: 1. NOT produced when the wort pH is above some threshold, 2. is only cleaned up when the wort pH is above some threshold (my current favorite), or 3. not detectable when the wort pH is above some threshold AND/OR dark roasted grain is present in sufficient quantities.

I think #1 is not correct because I taste my beer a lot throughout fermentation and I tasted the flavor on both good beers before they were done. I think #3 is not correct for the same reason. Note that this is not simply acetaldehyde. I am very sensitive to it and have used its disappearance as a cue to cask in the past with consistent results. It might be acetaldehyde plus some other factor though.

As for how S-04 seems to work, I think it wants to attenuate about 73-78%, depending on wort composition, works though simple sugars in 2 days, but takes another 3-5 to drop the last few gravity points and clean up. Between 65 and 70 it leaves a soft sweetness, warm bread, and generic light fruit in the background, with no fusels or twang, assuming wort pH is on the high side. If wort pH is on the low side, it reliably leaves a raw biscuit dough sourness that is universally unpleasant. These are my results--actual temperature range might be a little broader.

I hope some other brewers (with pH meters) look into this further. If my recent findings hold, S-04, when used within certain easy-to-maintain parameters, might be the answer to the age old question "is there a decent English dry yeast?" As for me, I am out of S-04 packets. I am going to try the Nottingham/Windsor combo in the next few brews. But these 2 (maybe 3) beers are good enough that I will use S-04 in the future, despite almost swearing it off for good.
I think the the connection mash ph and twang of the final beer is very likely not there. The yeast changes the environments ph to it's liking, no matter what ph it starts with (within reasonable borders of course). The yeast's preferable final ph should be the same no matter what, that's why I don't think that the initial ph plays a big role.

It's very interesting that you are noting that the tartness is disappearing with time. I've noticed the same and this fits perfectly with the habits of the notoriously impatient general home brewer, drinking their beers way too early.

Been there done that myself waaaaaaay to often!
 
Just to be clear, I'm not saying mash pH has something to do with the SO-4 twang. Based on what I see, it's the overall water chemistry. This is why I think some people report good results with this yeast only when being dark beers. For those people, I'm postulating that their "dark beer" water, when all is said and done, has way more alkalinity than their "pale beer" water. Regardless of what they do to get the mask pH in range.

As far as timing, I saw the flavor gone on the tenth day after pitching for one beer and day 4 for the other.
 
Just to be clear, I'm not saying mash pH has something to do with the SO-4 twang. Based on what I see, it's the overall water chemistry. This is why I think some people report good results with this yeast only when being dark beers. For those people, I'm postulating that their "dark beer" water, when all is said and done, has way more alkalinity than their "pale beer" water. Regardless of what they do to get the mask pH in range.

As far as timing, I saw the flavor gone on the tenth day after pitching for one beer and day 4 for the other.
Dark beer doesn't have more alkalinity as the alkalinity is removed by the acidity of the dark grist. It's basically gone once the malt hits the water, that's the whole point of adding for example baking soda.

But it could be connected to certain ion concentrations. Actual British brewing liquor is way more minerally than most us-ians would dare to add to their water.

This could be a reason for yeast from British origination to act weird.
 
Dark beer doesn't have more alkalinity as the alkalinity is removed by the acidity of the dark grist. It's basically gone once the malt hits the water, that's the whole point of adding for example baking soda.

But it could be connected to certain ion concentrations. Actual British brewing liquor is way more minerally than most us-ians would dare to add to their water.

This could be a reason for yeast from British origination to act weird.
Is the alkalinity removed or is it balanced? I was under the impression the both the positive and negative ions (generally) stay in solution, giving you a wort with more buffering capacity at whatever pH it finds equilibrium. Maybe we need a chemist--I'm just a mechanic.
 
Is the alkalinity removed or is it balanced? I was under the impression the both the positive and negative ions (generally) stay in solution, giving you a wort with more buffering capacity at whatever pH it finds equilibrium. Maybe we need a chemist--I'm just a mechanic.
No, they are not. They react and then they are basically "gone".
 
fwiw, I've been brewing ten gallon batches of a 1.107 OG imperial chocolate stout using S04 for many years using RO water with a TDS of 10 or less - so hardly any RA at all to start. That same RO water requires between 20 and 25 ml of 25% PA in the strike liquor for all of my other 10 gallon recipes, but for the stout I don't add any acid and live with a mash struggling to get above 5.19 at 70°F

If I was going to do anything different at all, I'd just hold back the 9 pounds of black (>300L) grains for 30~40 minutes. But tbh the beer always comes out wonderfully, which always leaves me wondering why so many folks are down on S04...

Cheers!
 
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