Astringency from Sparging?

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SRJHops

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I'm looking for the source of slight astringency in my beers. Mash ph is always within range; grain crush seems fine; no grains in the boil...

I batch sparge and it takes less than 10 minutes, so I've never checked the ph. (I thought checking the ph was more of a concern for fly sparging?)

I have a few theories:

1. I always thought the goal was to keep the grain/mash temperature below 170 when sparging. But I recently saw a tip that said to keep the sparge water below 170. I have been using water closer to 200, but I always check the mash temp to make sure it stays below 170. But maybe that initial blast of water at 200 is creating some astringency? Before I can mix it all in with the grain?

2. I always use ALL of my sparge water in order to reach my pre-boil volume. This means the very last bits of water are being sucked through the grains. Maybe I should just increase my sparge water by half a gallon and stop sparging when I reach the pre-boil volume?

3. I've read that getting some trub into the fermenter is not a big deal, but maybe I should really try to leave all of the trub behind? I saw a post that the hot break in the trub could cause astringency

Thoughts?
 
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SRJHops

SRJHops

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200F is probably too hot and could definitely be extracting tannins from the husk.
In How to Brew, Palmer says 165-175F is the best range for sparge water. Other sources pretty much agree.

Thanks. Yeah, that's probably it. I don't think people "mash out" anymore, but it's always been in the back of my mind that the grain bed should not exceed 170. But I will improve my process to make sure my sparge water is under 175.

I think as I started shaving time by being more efficient on brew day, I actually end up with hotter sparge water in the liquor tank. It used to sit a while and drop in temperature. Now I tend to use to pretty quickly.
 

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High sparge temp is only a cause of astringency if the pH gets above about 6 during the sparge. If high temp alone, or grain in the boil, caused astringency, no one would ever do a decoction mash.

Have you had the water you use for sparging tested for alkalinity? High alkalinity sparge water and high sparge temps (you need to have both) is the primary cause of astringency in beer. Sparge water alkalinity needs to be higher when batch sparging vs. fly sparging in order to extract tannins which are astringent.

An easy fix for high alkalinity sparge water is to add acid (lactic, phosphoric, etc.) to the water to reduce the pH to about 5.6. This will eliminate the possibility of sparging increasing the mash pH above 6.

Brew on :mug:
 
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SRJHops

SRJHops

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High sparge temp is only a cause of astringency if the pH gets above about 6 during the sparge. If high temp alone, or grain in the boil, caused astringency, no one would ever do a decoction mash.

Have you had the water you use for sparging tested for alkalinity? High alkalinity sparge water and high sparge temps (you need to have both) is the primary cause of astringency in beer. Sparge water alkalinity needs to be higher when batch sparging vs. fly sparging in order to extract tannins which are astringent.

An easy fix for high alkalinity sparge water is to add acid (lactic, phosphoric, etc.) to the water to reduce the pH to about 5.6. This will eliminate the possibility of sparging increasing the mash pH above 6.

Brew on :mug:

I use a calculator to predict the mash ph, and test that with a ph meter. Always hit between 5.2 and 5.5.

I use lactic acid to treat both the mash and sparge water at the same time. BUT I have never tested the ph of just the water before adding it to the grain.

The mash ph calculator includes the grains being mashed to make the ph prediction. So, what you are saying makes sense. From the water report, I know my untreated water has a ph of 9.04. For my last brew I added 9 ml of lactic acid to get my mash ph to 5.4.

But the ph of the both the mash and sparge water is likely higher than 5.4 because it has not mixed with any grains yet. So, it seems possible that the water ph is 6 (or higher), and the grains take it down to 5.4. Correct?
 

hotbeer

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Might you be mistaking a high alcohol content or dryness from the type of alcohols made as astringent? Usually that will be a hot burning taste when you have too many of the bad alcohols.

Astringency from the tannins of the malts is a different sort of dryness, not sure I can even describe it but I think I'll know it if I ever taste it.

Or maybe I'll just drink anything!
 
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SRJHops

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Might you be mistaking a high alcohol content or dryness from the type of alcohols made as astringent? Usually that will be a hot burning taste when you have too many of the bad alcohols.

Astringency from the tannins of the malts is a different sort of dryness, not sure I can even describe it but I think I'll know it if I ever taste it.

Or maybe I'll just drink anything!

It's certainly possible. My latest beer was fermented on the hot side, so some fusels may be in there. But I have gotten dinged by judges for astringency that I can't even notice, so I am thinking I might need to make some process improvements.

So far I have a few things to try next time, including not using too-hot sparge water and testing the sparge water ph. I won't change the mash water ph since it's been calculated with the grain, but I can test the remaining sparge water to see if the ph is 6 or above.
 

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I use a calculator to predict the mash ph, and test that with a ph meter. Always hit between 5.2 and 5.5.

I use lactic acid to treat both the mash and sparge water at the same time. BUT I have never tested the ph of just the water before adding it to the grain.

The mash ph calculator includes the grains being mashed to make the ph prediction. So, what you are saying makes sense. From the water report, I know my untreated water has a ph of 9.04. For my last brew I added 9 ml of lactic acid to get my mash ph to 5.4.

But the ph of the both the mash and sparge water is likely higher than 5.4 because it has not mixed with any grains yet. So, it seems possible that the water ph is 6 (or higher), and the grains take it down to 5.4. Correct?
A starting pH of 9.4 doesn't tell you much, as that could be either low or high alkalinity (depending on the mineral content of the water.) It's the amount of alkalinity that determines how much the sparge water can shift the pH of the sparged mash. pH 9.4 with low alkalinity can't shift the pH of the mash much, so isn't likely to be a problem. High alkalinity, even at pH near neutral, can shift the mash pH a lot. Acidifying the sparge water (to pH less than 6) basically eliminates the alkalinity of the sparge water, therefore making it impossible for the sparge to affect the pH of the mash.

9 ml of lactic acid is quite a bit for a 5 gal batch, which is another indication that your starting water has significant alkalinity.

The way I use my water calculator is to adjust the strike water with additions to hit a target mash pH, and add just enough acid to the sparge water to drop the pH of the sparge water to around 5.6 before sparging.

Brew on :mug:
 
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SRJHops

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A starting pH of 9.4 doesn't tell you much, as that could be either low or high alkalinity (depending on the mineral content of the water.) It's the amount of alkalinity that determines how much the sparge water can shift the pH of the sparged mash. pH 9.4 with low alkalinity can't shift the pH of the mash much, so isn't likely to be a problem. High alkalinity, even at pH near neutral, can shift the mash pH a lot. Acidifying the sparge water (to pH less than 6) basically eliminates the alkalinity of the sparge water, therefore making it impossible for the sparge to affect the pH of the mash.

9 ml of lactic acid is quite a bit for a 5 gal batch, which is another indication that your starting water has significant alkalinity.

The way I use my water calculator is to adjust the strike water with additions to hit a target mash pH, and add just enough acid to the sparge water to drop the pH of the sparge water to around 5.6 before sparging.

Brew on :mug:
A starting pH of 9.4 doesn't tell you much, as that could be either low or high alkalinity (depending on the mineral content of the water.) It's the amount of alkalinity that determines how much the sparge water can shift the pH of the sparged mash. pH 9.4 with low alkalinity can't shift the pH of the mash much, so isn't likely to be a problem. High alkalinity, even at pH near neutral, can shift the mash pH a lot. Acidifying the sparge water (to pH less than 6) basically eliminates the alkalinity of the sparge water, therefore making it impossible for the sparge to affect the pH of the mash.

9 ml of lactic acid is quite a bit for a 5 gal batch, which is another indication that your starting water has significant alkalinity.

The way I use my water calculator is to adjust the strike water with additions to hit a target mash pH, and add just enough acid to the sparge water to drop the pH of the sparge water to around 5.6 before sparging.

Brew on :mug:
The starting alkalinity from the tap was 73 ppm Cac03. Not sure if that is high or low?

Makes sense to treat the waters differently. I have seen that option on the water calculator. It just always seemed easier to treat all the water at once. (Which is probably why 9 ml seems high to you. I frequently use more.)

I will test the sparge water pH next time. I have time during the mash.
 

doug293cz

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The starting alkalinity from the tap was 73 ppm Cac03. Not sure if that is high or low?

Makes sense to treat the waters differently. I have seen that option on the water calculator. It just always seemed easier to treat all the water at once. (Which is probably why 9 ml seems high to you. I frequently use more.)

I will test the sparge water pH next time. I have time during the mash.
Alkalinity of 73 ppm is in the medium range. Mine is very low (20 - 25). I would say high is above 150.

Brew on :mug:
 
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SRJHops

SRJHops

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A starting pH of 9.4 doesn't tell you much, as that could be either low or high alkalinity (depending on the mineral content of the water.) It's the amount of alkalinity that determines how much the sparge water can shift the pH of the sparged mash. pH 9.4 with low alkalinity can't shift the pH of the mash much, so isn't likely to be a problem. High alkalinity, even at pH near neutral, can shift the mash pH a lot. Acidifying the sparge water (to pH less than 6) basically eliminates the alkalinity of the sparge water, therefore making it impossible for the sparge to affect the pH of the mash.

9 ml of lactic acid is quite a bit for a 5 gal batch, which is another indication that your starting water has significant alkalinity.

The way I use my water calculator is to adjust the strike water with additions to hit a target mash pH, and add just enough acid to the sparge water to drop the pH of the sparge water to around 5.6 before sparging.

Brew on :mug:
So, I am rebrewing the beer that had astringency IMO. I just tested the sparge water and it's 4.0 ph. So, that likely means it was under 6 last time... So even if I sparged too hot, it should not have caused astringency, correct?

So where did it come from..?

Someone on this thread mentioned alcohols... Can fusels be mistaken for astringency?

I did ferment too hot... And I got a really harsh bitterness that I thought was astringency... Kind of a harsh drying bitterness for the finish/aftertaste.
 

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I was having a similar issue. Whatever I did, the beer just tasted slightly astringent.
That wasn't the kind of Lactic or Acetic acidity infections give, it was a different flavour, I suppose that was Tannic astringency.
Then I read on this forum a posting by a guy who sparged COLD and decided to give that a try.

When I started fly-sparging my grain with 45C/104F water the astringency was gone.
Even if there's some decrease in efficiency, it must be negligible at the homebrewing level. I didn't notice any.
 

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If your sparge liquor is pH 4.0, it will have zero alkalinity and is unlikely to extract tannins as I can't immediately think of any grist that might possibly allow wort pH to reach 6.0. With mash liquor that acidic, it would seem the liquor has little calcium present to deposit phosphates, oxalates and other unessential extracts and protect enzymes from the hostile environs of the mash. Low calcium is usual for some beers, but these normally lagered to clear and mature. If you are brewing ales don't lager, I would advise you have a minimum of 100 ppm calcium and marginally reduce the acid additions.
 
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SRJHops

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I was having a similar issue. Whatever I did, the beer just tasted slightly astringent.
That wasn't the kind of Lactic or Acetic acidity infections give, it was a different flavour, I suppose that was Tannic astringency.
Then I read on this forum a posting by a guy who sparged COLD and decided to give that a try.

When I started fly-sparging my grain with 45C/104F water the astringency was gone.
Even if there's some decrease in efficiency, it must be negligible at the homebrewing level. I didn't notice any.
Cool (pun intended), I will give it a try.

I wonder why the water needs to be hot in the first place? We are rinsing sugars, not mashing. But then there is the mashout that I have never quite understood.

I also read that you are supposed to stop sparging when your ph hits X (is it 6?). This implies that the ph changes when sparging... So what is happening?
 
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SRJHops

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If your sparge liquor is pH 4.0, it will have zero alkalinity and is unlikely to extract tannins as I can't immediately think of any grist that might possibly allow wort pH to reach 6.0. With mash liquor that acidic, it would seem the liquor has little calcium present to deposit phosphates, oxalates and other unessential extracts and protect enzymes from the hostile environs of the mash. Low calcium is usual for some beers, but these normally lagered to clear and mature. If you are brewing ales don't lager, I would advise you have a minimum of 100 ppm calcium and marginally reduce the acid additions.
That's a bit over my head, which goes to show there is always more to learn... But I can certainly raise my calcium. I usually just get it to 50.

I could use acidified grain instead of a lactic acid, but I can't really reduce the acid and hit my mash ph. Unless I switch to RO, which I don't want to do.
 

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I (heretically, maybe) suspect that many of the requirements regarding low mash pH and high sparging/mashout temps originating from industrial brewing are transferred into homebrewing with little sufficient grounding. I noticed very little difference playing with those variables at my tiny scale.
Your Mileage May Vary, of course.
 

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I wonder why the water needs to be hot in the first place? We are rinsing sugars, not mashing. But then there is the mashout that I have never quite understood.

I also read that you are supposed to stop sparging when your ph hits X (is it 6?). This implies that the ph changes when sparging... So what is happening?
Hot water dissolves more sugar than will cold and takes less time and power to boil.

pH 5.6 is the upper limit for me and don't stop until over 90% of sugars are extracted, but that's another story

Sugars in the mash act as a buffer trying to maintain mash pH, but as those are rinsed from the grains, that power declines. Mind, I wouldn't expect there to be much rise with sparge liquor at pH 4.0.

That's a bit over my head, which goes to show there is always more to learn... But I can certainly raise my calcium. I usually just get it to 50.

I could use acidified grain instead of a lactic acid, but I can't really reduce the acid and hit my mash ph. Unless I switch to RO, which I don't want to do.
There is lots to learn, but beware some of what you find might not be valid. 50 ppm calcium is at the lowest level for ales, more usual for lager brewing, so keep some cold for a month or so to see if the problem fades.

Acidified grains simply include lactic acid. Sparging with RO water will increase pH than will your water treated to pH 4.

I (heretically, maybe) suspect that many of the requirements regarding low mash pH and high sparging/mashout temps originating from industrial brewing are transferred into homebrewing with little sufficient grounding. I noticed very little difference playing with those variables at my tiny scale.
Your Mileage May Vary, of course.

British brewers don't usually mashout, most who do have followed American practice. I think a great many homebrewers have found what you describe, and certainly an ideal pH does not ensure the production of a great beer, good brewing does that. However, a wrong pH can spoil even the best of brewmanship.
 

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Hot water dissolves more sugar than will cold and takes less time and power to boil.

No offense, but this is a bit of a misconception. Yes, sugars are more soluble in hot water, but this only applies to sugar concentrations far, far beyond that which can be achieved in a mash. With this in mind, a sparge is only rinsing the grain of sugar that is already in solution. It doesn't matter what temperature you use, it won't make more sugar go into solution. So, cold water works as well as hot water. The only downside is that a cold sparge then requires more time/energy to bring the wort to a boil.
 

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No offense, but this is a bit of a misconception. Yes, sugars are more soluble in hot water, but this only applies to sugar concentrations far, far beyond that which can be achieved in a mash. With this in mind, a sparge is only rinsing the grain of sugar that is already in solution. It doesn't matter what temperature you use, it won't make more sugar go into solution. So, cold water works as well as hot water. The only downside is that a cold sparge then requires more time/energy to bring the wort to a boil.
Indeed so, but more so when a cold water sparge stops the processes that happen between 60 and 70 centigrade. Similar is true after a mashout that destroys remaining enzymes. As said, I'm British where we tend not to mash out and the process continues while sparging. Here malts are in general lower in nitrogen and enzymes compared to the likes of Breiss base malts. I mash for 90 minutes and sparging normally takes place over 2 hours, also without astringency.
 

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No offense, but this is a bit of a misconception. Yes, sugars are more soluble in hot water, but this only applies to sugar concentrations far, far beyond that which can be achieved in a mash. With this in mind, a sparge is only rinsing the grain of sugar that is already in solution. It doesn't matter what temperature you use, it won't make more sugar go into solution. So, cold water works as well as hot water. The only downside is that a cold sparge then requires more time/energy to bring the wort to a boil.
Yes, the saturation concentration of maltose at 150°F (65°C) is 66.7% (66.7°P), which corresponds to an SG over 1.300. There is no way to get sugar concentration that high in a mash. Also, the sugar in the mash is created one molecule at a time, and those molecules are in solution as soon as they are created. There is never any solid sugar in a mash to be be dissolved. Sparging is only dilution.

Sparging with cold water does result in a longer time to reach boil, but is does not use more energy, just changes when that energy is expended. Cold water sparging may actually use a little less total energy to get to boil, since the total volume heated is a little less due to grain absorption. If you heat excess sparge water volume, then you use even more energy heating the extra water. Loss of heat to the environment can vary widely from system to system, and will also affect total amount of energy to complete the mash and heat to boil.

Whether or not a hot sparge will create more sugar than existed at the start of sparging depends on whether or not the mash has reached 100% conversion. If so, there will be no additional sugar created during the sparge (although fermentability may increase with time if no mash-out was done.) If the mash was not completely converted, and there was no mash-out done, then saccharification can proceed further during the sparge, and the SG of the pre-boil wort will be increased.

Indeed so, but more so when a cold water sparge stops the processes that happen between 60 and 70 centigrade. Similar is true after a mashout that destroys remaining enzymes. As said, I'm British where we tend not to mash out and the process continues while sparging. Here malts are in general lower in nitrogen and enzymes compared to the likes of Breiss base malts. I mash for 90 minutes and sparging normally takes place over 2 hours, also without astringency.
I assume you are talking about a mash that has not reached 100% conversion when you say: "stops the processes that happen between 60 and 70 centigrade."

Brew on :mug:
 

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Sparging with cold water does result in a longer time to reach boil, but is does not use more energy, just changes when that energy is expended. Cold water sparging may actually use a little less total energy to get to boil, since the total volume heated is a little less due to grain absorption. If you heat excess sparge water volume, then you use even more energy heating the extra water. Loss of heat to the environment can vary widely from system to system, and will also affect total amount of energy to complete the mash and heat to boil.
Right, good point, I neglected to consider the energy used heating the sparge water.
 

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I assume you are talking about a mash that has not reached 100% conversion when you say: "stops the processes that happen between 60 and 70 centigrade."

Brew on :mug:

Not entirely, but you've put your finger on my point by your question.

Wort is a highly complex medium, but it is often spoken of as if sugar production is the sole object of a mash. An enzyme rich, lightly kilned malted barley might convert in 10 minutes, but the result is unlikely to easily make the perfect beer. This post widens the subject by asking about avoiding unwanted products from a mash, while other products will aid fermentation.

We often read advice to allow break and trub to reach the FV, but rarely hear of the individual products , such as Free Amino Nitrogen, that do aid fermentation, provided they have the right conditions to be produced in the mash.
 
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