Astringency from Partial Mash/Sparge?

[butterblum]

Hey guys, I have had an issue with what I believe to be astringency in my last couple of IPAs (doesn't seem to be excessive hop bitterness, but it leaves a real dryness on the tongue).
Here is my partial mash method:
1) Preheat my mash tun (small Igloo cooler) with hottest tap water possible
2) Heat my carbon-filtered tap water (1.25 qt/lb.) that is treated with just a bit of gypsum to about 170 degrees
3) Add 170 degree treated mash water and grain (usually 2 lbs of base grain and another 2 lbs of specialty malt) to mash tun, which settles to about 154 degrees
4) Let sit at 154 degrees for an hour
5) During mash, heat up same amount of water (just carbon-filtered, no salts) to 170 degrees
6) Drain runnings into brew kettle, trying to recirculate and filter the wort through the grain bed by hand
7) Once drained, add 170 degree sparge water and let sit for 10 minutes
8) Drain sparge water, recirculating by hand to filter

Is there anything obvious that I am doing wrong? Which step could be causing the astringency?
I don't remember having these flavors until I switched to this mash/sparge set-up. (I previously just soaked the grains using a muslin bag and ran water through the bag after the soak)
I have already ordered some pH strips to test mash pH.
Thanks

 

[mattdee1]

Non-ideal water chemistry could be causing the off flavors, but there is no way of knowing with the info you've provided.

Most seem to agree that pH strips are pretty useless because they're not accurate enough.

The quickest way to either rule out or confirm a water problem is to re-brew a recipe that had the astringency issue, only this time use reverse osmosis (RO) water with additions calculated from a tool like Bru'N Water. For pale colored beers, the only additives you'll need are Gypsum, Calcium Chloride, and acid (e.g., lactic or phosphoric).

 

[IslandLizard]

Your methods look sound, there are a few details to consider.

If your tap water contains a lot of alkalinity, your mash pH will be too high, and your sparge water pH even higher and possibly leeching tannins. The pH of the mash during sparging should remain under 6.0, preferably under 5.8.

If you use municipal water, do you treat for Chlorine or Chloramines by stirring in 1/4 crushed Campden tablet or a pinch of K-Meta per 5 gallons? A carbon filter will NOT remove those or effectively.

Agreed on the mash pH strips, the lack of accuracy is one thing, it's also impossible to read them, the patches are shades of brown.

 

[IslandLizard]

Once you know your water composition (or use RO or distilled water) you can use a mash/sparge water calculator.

Bru'n Water, is a very good water calculator, used it for many years. But since Mash Made Easy was released I prefer to use that instead. It's a bit simpler, and definitely easier to use, with the same or even better results.

A $25 water mineral test (Ward Labs) is the only way to find out your water composition, just send them a sample, no need to buy a kit. But it's a snapshot, and only useful if your water source is stable. If it fluctuates a lot, you'd still be in the dark.

You could contact your municipal water agency, and get to talk to the right person. They know your water the best, where it comes from and how much it fluctuates over the seasons. That person can also give you the mineral composition.

 

[butterblum]

Your methods look sound, there are a few details to consider.

If your tap water contains a lot of alkalinity, your mash pH will be too high, and your sparge water pH even higher and possibly leeching tannins. The pH of the mash during sparging should remain under 6.0, preferably under 5.8.

If you use municipal water, do you treat for Chlorine or Chloramines by stirring in 1/4 crushed Campden tablet or a pinch of K-Meta per 5 gallons? A carbon filter will NOT remove those or effectively.

Agreed on the mash pH strips, the lack of accuracy is one thing, it's also impossible to read them, the patches are shades of brown.

Thanks for the input. I do know that my water chemistry swings with the seasons.
I am curious as to the effect of the filter; it is a granular carbon activated filter. There is a noticeable difference in the mouth feel of the treated water and the regular tap water; being, the treated water is much drier - which would seem to fit with the theory that it is stripping the water of chloride ions.

 

[IslandLizard]

Thanks for the input. I do know that my water chemistry swings with the seasons.
I am curious as to the effect of the filter; it is a granular carbon activated filter. There is a noticeable difference in the mouth feel of the treated water and the regular tap water; being, the treated water is much drier - which would seem to fit with the theory that it is stripping the water of chloride ions.

As long as you know the water chemistry is a function of the seasons, there is little gain in sending a sample to Ward.

How much do your water minerals fluctuate? Do you know their levels? If they're still low, there's little concern.

For brewing, we're basically only interested in:

Ca++
Mg++
Cl-
SO4--
Na+ (and K+)
Alkalinity

with ppm values as low as possible, ideally, although some are manageable at higher rates or fine for certain styles. We can always "dilute" our tap water with some RO or distilled.

All other ions we don't want any of, no higher than a few ppb, or a few ppm for some.

If your water is not very suitable for brewing, there are 2 solutions:
1) Buy RO water at Wally's Mart (or some supermarkets) for $0.39 a gallon (plus the drive), or
2) buy your own RO system for ~$200 plus a TDS meter for $10-15 and virtually unlimited brewing (and drinking, cooking) water.

At that price, your break even point will be around 85 5 gallon batches, not counting your mileage to Wally's, which may easily half, quarter, or better your break even point.

Water mineral test kits are still ridiculously expensive, giving you ~50 tests each of various minerals for $200+, not counting a pH meter. Alkalinity and hardness (Ca and Mg) can be tested fairly cheaply with an extended pool testing kit.

[Active] carbon filters do not filter out minerals, such as chlorides (Cl-). At very slow flow rates (<1 liter / min) they will trap a large percentage of Chlorine (Cl2), and (larger) organic molecules.

Drier water?
Do a blind triangle test with your water, carbon filtered and unfiltered, and see how well you can tell the one that's different; invite anyone you want for a larger testing pool. If there's chlorine or chloramines in your water, treat with a grain of K-meta and taste test again, the same way.

 

[butterblum]

Drier water?
Do a blind triangle test with your water, carbon filtered and unfiltered, and see how well you can tell the one that's different; invite anyone you want for a larger testing pool. If there's chlorine or chloramines in your water, treat with a grain of K-meta and taste test again, the same way.

I have had others taste the difference. After drinking the water run through the filter, it will literally leave your mouth feeling drier than before you drank it.
Likewise, the water that has not been run through the filter is 'wet' and it actually tastes refreshing.
This is exactly how I have heard people describe the high sulfate and low chlorine balance vs. the low sulfate and high chlorine balance.

 

[IslandLizard]

I have had others taste the difference. After drinking the water run through the filter, it will literally leave your mouth feeling drier than before you drank it.
Likewise, the water that has not been run through the filter is 'wet' and it actually tastes refreshing.
This is exactly how I have heard people describe the high sulfate and low chlorine balance vs. the low sulfate and high chlorine balance.

Again, your carbon filter cannot filter out minerals and thus change their ratio.

Perhaps someone in the brew science forum can shine a light on why you perceive a noticeable difference in mouthfeel between unfiltered and carbon filtered water, and what causes it.

In general carbon filtered water has less flavor than unfiltered, due to off flavors being absent. Never heard about a negative mouthfeel difference before. I'm curious too.

 

[butterblum]

Again, your carbon filter cannot filter out minerals and thus change their ratio.

Perhaps someone in the brew science forum can shine a light on why you perceive a noticeable difference in mouthfeel between unfiltered and carbon filtered water, and what causes it.

In general carbon filtered water has less flavor than unfiltered, due to off flavors being absent. Never heard about a negative mouthfeel difference before. I'm curious too.

I am curious too. Maybe I will start brewing with RO water and just eliminate most of the evaluation and guess work.
I would hate to keep wasting money and time on beer by using poor quality water.

 

[IslandLizard]

I am curious too. Maybe I will start brewing with RO water and just eliminate most of the evaluation and guess work.
I would hate to keep wasting money and time on beer by using poor quality water.

Just been thinking about it for a few days, maybe you have some iron or manganese or something else in your water causing that dryness.

Since it fluctuates per your water company's testimony, a snapshot test (Ward's) is futile, except to know what's in there at that point.

The most common advice usually given is to brew the same recipe with 100% RO water and see if the problem goes away. That would point to your water. Then take it from there.

You're not in Flint, MI, are you?

 

[butterblum]

Just been thinking about it for a few days, maybe you have some iron or manganese or something else in your water causing that dryness.

Since it fluctuates per your water company's testimony, a snapshot test (Ward's) is futile, except to know what's in there at that point.

The most common advice usually given is to brew the same recipe with 100% RO water and see if the problem goes away. That would point to your water. Then take it from there.

You're not in Flint, MI, are you?

I have attached 2 past water reports for my area (one file).
Anything odd here?

 

[IslandLizard]

Sorry I don't see the attachments.

 

[butterblum]

Follow up:
I recently brewed a 2.5 gal Session IPA and had a similar problem. I used Chinook and Centennial as bittering hops, and I used RO water while following Bru'n Dog's Pale Ale water profile to a 'T'.
I DID adjust my single step batch sparge with phosphoric acid - so I don't think tannin extraction is a problem. I had to use 170deg strike water during my mash-in, which quickly dropped to 156.
My guess is that the harshness either comes from the hops, or it is from maybe too much sulfate in the water.
Does anyone perceive Bru'n Dog's Pale Ale profile to use too much sulfate?
OR if I plug in 2 gallons of mash water and 2 gallons of sparge water into Bru'n Water, does it take into account boil-off? By boiling off 1.25 gallons, have I effectively increased the concentration of minerals and ions in the water to an insane amount?
Thanks