Moving from tap water to RO water

[ziggityz]

I've been using tap water and adjusting it using a water spreadsheet. I have been getting a dry/bitter almost astringent taste in most of my beers since and I'm finally noticing a pattern. A friend said it could be due to excessive pH in my mash. Would using RO water fix this problem if the high pH is indeed the problem?

 

[dogslapbrewery]

Ultimately there are so many variables when adjusting your pH. Different malts, mash ratio, temperature, if you really want to play around with it especially with RO water you'll need a good pH meter. I live in western New York near a large natural water source so I use filtered tap and found a good average salt addition for lighter SRM brews and leave it alone for darker brews. I wouldn't get to caught up on hitting exactly 5.2 and just follow your taste buds.

 

[acidrain]

If you know your starting point whether it's RO water, or tap water, you can enter it into any of the good on-line brewing water programs like Brewer's Friend, and then tell it what your grain bill is, and it will tell precisely what your PH will be, and if you are within any of the brewing water beer styles. I have a PH meter, but rarely use it any more.
Do you know your tap water profile? That is the first place to start. Ward Labs is highly recommended.

 

[sky4meplease]

Just using R/O water will not fix the problem unless you are only brewing low SRM beer styles.
Your current water will be a match for a particular SRM and when you sway one way or the other it will drive your ph up or down. At some point depending on how far you sway it will affect the beer negatively.
The higher the SRM the lower your ph will go and the lower the SRM the higher it will go.

 

[JonM]

Also, Palmer's "Water" book is a great resource to help understand water chemistry. FWIW, switching to RO water and using proper additions and measuring pH, along with the use of software like Bru'n Water, has led to much, much better beer.

 

[mabrungard]

Switching to RO will not necessarily solve your tannic astringency problems. While the RO water should solve any issues with excessive sparging water alkalinity, it may not solve high mash pH. If you are brewing a pale beer, you are likely to still have to add acid to the mash to bring the pH lower. An important fact is that pale malt mashed with distilled water only produces a pH of around 5.7 to 5.8. That is several tenths higher than we want in the mash. That is why the external acid addition is needed. It can be an acid addition, acid malt addition, or calcium addition to create acids from the mash.

By the way, I found that an important factor in reducing tannin extraction is to be sure to stop your runoff before the wort gravity gets too low. I now stop around 3 brix (1.012) and solved my tannin extraction that was present when I let my runoff gravity drop to 2 brix (1.008).

 

[ScrewyBrewer]

I've been using tap water and adjusting it using a water spreadsheet. I have been getting a dry/bitter almost astringent taste in most of my beers since and I'm finally noticing a pattern. A friend said it could be due to excessive pH in my mash. Would using RO water fix this problem if the high pH is indeed the problem?

No it alone wouldn't. RO water has zero buffering which means the pH of the mash will easily push the RO water into the 5.6 or higher range if using low acid malts. Now if you added acid and base to the RO water, using EZ WaterCalculator or other brewing water profilers, you can create a buffer with a sweetspot in the 5.2 - 5.6 pH range that will resist pH changes at mash temperature.

Adding salts and minerals like calcium chloride, gypsum and Epsom salt will help create the buffering while restoring flavor to the RO water.

 

[sky4meplease]

Your grain bill will be doing the buffering and will drive the ph in your beer.
The higher the percentage of specialty grain in your bill will up the buffering capacity in your mash. That is why your current water will have a sweet spot as it relates to SRM.
Since the ideal ph range is 5.2-5.6 you have some wiggle room but if you are brewing a very light or very dark beer (depending on the composition of your current water) the buffering capacity of your grain bill in the mash will be too high or too low and leave you outside of the ideal ph range.
That is what is nice about using R/O water when you don't know the composition of your current water source because you know what is in the R/O water....nothing. However, you can't just use R/O water and expect it to fix your problems. You will have to have a small handful of different brewing salts on hand to add to the R/O water to tailor it to your specific brew. Very light beers (6 SRM and lower) will use very little salt while dark beers (20 SRM and higher) will use 1/8-1/4 cup and everywhere in between. If your math skills like mine suffer then find a good online source to help calculate the amounts.
Now... If you know what is in your current brewing water you can make adjustments to go higher with brewing salts but if the current levels are already high then you will need to dilute with R/O water or boil to precipitate out some of what you don't want and then you don't really know what is in your water again. Another argument for using R/O water.
In conclusion, a lot of Brewers are making great beers without giving much thought to water. Take out the chlorine, toss in a tablespoon or two of gypsum and brew on. If you want to have control over how your brewing water will effect your finished beer then you will have to either find out what is in it now or start from scratch with water that has nothing.

 

[VladOfTrub]

OP. When other people drink your beer do they notice the astringency?
Looking into water chemistry is very important. You shouldn't have any problem fixing the issue. If you adjust the water and still have the issue, explaining the process that you use will help with figuring things out.
When you read about brewers that stop the run off at 1012 gravity. The brewer is assuming that the pH hasn't risen above 5.8. When a brewer uses that method, it's an indication that they don't own a pH meter. So, the conclusion would be: the brewer has no idea what the mash pH is throughout the brewing process nor what the wort pH is before or after boiling. If chemicals are added, the brewer has no idea what affect they had on mash pH. All that the brewer knows is that the last sample of run off has sugar in it. It's a tough way to brew beer.
It's not a bad idea to get the data sheet on the malt that you use. There is a lot of info on it that a brewer needs, one being inherent pH.
When using the English method and "sticking" the mash at one set pH and at one set conversion temperature, you have to take what you get from whatever enzyme is doing most of the converting. Mother Nature is in control of the process, not the brewer. She will give you something called beer. It just might not be the beer that you thought you were going to end up with.

"The ideal pH of mash is 5.2 to 5.6."
The word "ideal" makes it a very broad statement. If you have an understanding of enzymatic action, you will see how broad the statement is. If I were to use a conversion temperature of 155F, what should the mash pH be? Oh yeah, that's right. Somewhere between 5.2 to 5.6.
Close is OK in horseshoes and hand grenades, not in brewing.

Since, there is an optimum temperature range for enzymes, there is an optimum pH range, as well. A couple of points outside of the optimum pH of an enzyme, and enzymatic action slows down or stalls.

 

[bigdongsr94]

Let me make everybody mad. Yes using RO can fix pH issues and astringency if caused by high pH. I have a pH meter and dont use it anymore as well...because i use brunwater and RO water. So i add to the RO 2-3 tsp Gyspum with one tsp calcium chloride for an IPA and 1tsp of each for a malty beer. Then i just use brunwater to make sure my mash thickness keeps the pH between 5.2-5.4. I do use lactic for the sparge water but i just use the sparge sheet in brunwater to calculate that as well. Its not as complicated as all are saying...That being said, a pH meter is cheap (hannah beer checker amazon $30) and wards is cheap too so you can go that route as well.

 

[trentm]

When you read about brewers that stop the run off at 1012 gravity. The brewer is assuming that the pH hasn't risen above 5.8. When a brewer uses that method, it's an indication that they don't own a pH meter. So, the conclusion would be: the brewer has no idea what the mash pH is throughout the brewing process nor what the wort pH is before or after boiling. If chemicals are added, the brewer has no idea what affect they had on mash pH. All that the brewer knows is that the last sample of run off has sugar in it. It's a tough way to brew beer.

Careful, everything I know about bru'n water I learned from this "brewer". Check out his website: https://sites.google.com/site/brunwater/

 

[VladOfTrub]

"Careful, everything I know about bru'n water I learned from this "brewer"."

I believe your statement.
You have learned everything about water chemistry and brewing beer from a "brewer" that advises brewers to adds chemicals to the brewing water/mash, who brews astringent beer and uses an hydrometer to correct the problem. Interesting.
The brewing process along with the chemical/acid additions aren't working right. It's hard to find credibility in advise or recommendations about water chemistry, when the advise or recommendations don't work for the person giving the advise.

 

[mabrungard]

When you read about brewers that stop the run off at 1012 gravity. The brewer is assuming that the pH hasn't risen above 5.8. When a brewer uses that method, it's an indication that they don't own a pH meter. So, the conclusion would be: the brewer has no idea what the mash pH is throughout the brewing process nor what the wort pH is before or after boiling.

Vlad had a good point regarding the need to stop at 1.012 to avoid tannin extraction...or was it due to a rise in runoff pH? At the time, I didn't have that answer. Was it a problem with the pH?

I use RO water with verified low TDS, so I assumed that pH would not rise regardless of the runoff gravity. But I had not been monitoring pH that late in the process and did not know.

With the last brew, I did that monitoring. I can report that there is no pH rise with extended runoff and low gravity when using straight RO with no acidification. Gravity fell as low as 1.006 and the pH was still around 5.4. So it appears that some 'advice' provided in this thread can be taken with a grain of salt.

 

[helibrewer]

To answer the enzyme vs. pH question, this chart is useful: