RO water and harsh bitterness

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rockeye84

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Up until recently I've always used rain water with good results, when I upgraded my brew house, bigger vessels & elements etc, I thought it a good idea to get an RO unit, with no rainwater tank it's a mission to lug 140l of rainwater from my grandparents house every time I want2 brew, so Ro unit us much more convenient.

every brew I've done with RO water with +20ibu has harsh lingering bitterness. Made a 36ibu pale ale and its bordering on undrinkable.

Switched back to rainwater, to rule out my new setup, made the exact same brew, bitterness smooth and nice.

My mains water is 7.5 ph & 850ppm tds & comes out at 20ppm tds after the filter.

Have tried dialling down then mineral salt additions to a minimum. Balanced Cl/so4, @. 50ppm etc still pretty harsh. Tried pushing the Cl. Still no joy.4

I never really considered post boil wort ph as an issue, I've come to the conclusion my boil ph is too high, which leads to greater hop utilisation thus giving harsh bitterness. Measured my last batch post boil, it was approx 6.5ph.

Any suggestions? Hit the kettle with some lactic acid or some say add calcium to the boil, or harden & acidifying all your brewing water be4 mashing in.
 
What is the mash ph? 6.5 seems high but I'm not sure what it should be post boil, I only measure and have read about mash ph. However my understanding is that high mash ph may cause high tannin extraction and astringency, possibly explaining what you are interpreting as bitterness. If that is the case, just need to manage mash ph and possibly question the RO unit as it should leave u with neutral water not capable of 6.5 post mash.
 
Agree with the above, tannin extraction in your mash starts above pH 5.8. Start checking your mash pH.
Finished beer should be @ pH 4 to 4.5.
 
pH is important all the way through although if your mash pH is right, the rest should hopefully follow. You may need to adjust your sparge water.

Check, using decent measuring equipment what your strike and sparge water are and check your mash pH on a standard, average coloured brew. Have some food grade acid on hand to adjust.

Without knowing any more about process and ingredients, it is hard to say but wort pH should be lower than mash pH (very low 5s) and mash pH should be much lower than 6.5
 
rockeye84 said:
Up until recently I've always used rain water with good results, when I upgraded my brew house, bigger vessels & elements etc, I thought it a good idea to get an RO unit, with no rainwater tank it's a mission to lug 140l of rainwater from my grandparents house every time I want2 brew, so Ro unit us much more convenient.
every brew I've done with RO water with +20ibu has harsh lingering bitterness. Made a 36ibu pale ale and its bordering on undrinkable.
Switched back to rainwater, to rule out my new setup, made the exact same brew, bitterness smooth and nice.
My mains water is 7.5 ph & 850ppm tds & comes out at 20ppm tds after the filter.
Have tried dialling down then mineral salt additions to a minimum. Balanced Cl/so4, @. 50ppm etc still pretty harsh. Tried pushing the Cl. Still no joy.4
I never really considered post boil wort ph as an issue, I've come to the conclusion my boil ph is too high, which leads to greater hop utilisation thus giving harsh bitterness. Measured my last batch post boil, it was approx 6.5ph.
Any suggestions? Hit the kettle with some lactic acid or some say add calcium to the boil, or harden & acidifying all your brewing water be4 mashing in.
Are you sure that your RO filter is working correctly.
Do you have a TDS meter to test the output?
If the membrane is bypassing and then you are adding salts to your water it will be way off the anticipated result.
And then what manticle said in the above post......

You will need a PH meter to achieve the correct mash PH 5.2 to 5.6 will be OK
Acidulated malt or acid will provide PH adjustment in the mash.
If mash and sparge PH is correct then the beer really takes care of itself.
 
RO water is not suitable for drinking if all the salts and minerals are removed when they recycle water calcium has to be added to the water to stop the water from dissolving concrete.
 
wynnum1 said:
RO water is not suitable for drinking if all the salts and minerals are removed when they recycle water calcium has to be added to the water to stop the water from dissolving concrete.
Is this April 1st already? :blink: :blink: :blink:
 
RO water is completely suitable for drinking if you have a balanced diet.
rockeye, there's no chance you've mixed up the waste water with the 'good' water is there? What's the pH of the RO water? I'm not sure how you could possibly have a pH of 6.5 post-boil without having extremely alkaline water to start with.
 
Have a tds meter, the water tests at 21ppm tds. The filter is configured properly, waste water is going down the drain as it should.

Got a water report from the water Corp, ph is 7.5 before the filter. Had a ph meter but it broke, so I can't test after.

Tested post boil wort with test strips, came in at 6.5 ph. Didn't test mash ph.

Has to be the water, do nothing different with rainwater and beer turns out fine.

I'm convinced it's high boil ph causing this harsh *** bitterness. I've tried everything else.

When sparging I stop at 1.008-10, but end up with 3/4 of my desired volume, to reach target gravity and volume I had to add about 25L of water. Could that screw up my boil ph?

Next batch I'll make sure mash ph is bang on, then check my post boil ph, if it's off what's the best way to adjust post boil ph? Add lactic acid?
 
I use Citric Acid for mash and sparge water. Unless I learn of better. Its only tiny bits make the difference. Like 1 gram for a mash of 8kg grain with 23lt water to drop from PH 5.6 to 5.2. I mix in a smidgeon 1/32 tsp at a time until its 5.2. Or Acid Malt ~3% but that's pre mash guess work. I've just got a good PH meter and fine adjusting now. Learning every brew that everything has different effects. Pressure brewing now as well my IBU's seem higher than usual.
 
rockeye,

I calculate the required total volume of water (Beersmith) and treat all the water the same.

I use EZ water spreadsheet and that spreadsheet will allow you to achieve what ever water profile you want.

The reason I calculate and adjust my entire volume of water as one adjustment is because I have a Braumeister and I choose not to sparge.

I know that some brewers treat there mash and sparge water separately but I have never done that even when I had a 3v system.

If all your volumes are correct and your mash PH is correct then as I said before, the beer will take care of itself.

By using the spreadsheet i always know my Chloride / Sulphate ratio and the required calcium for each individual recipe.

Without knowing all the details of your additions and ingredients it will be difficult for anyone to put their finger on your problem.

Just as a matter of interest seeing that this problem appears when using RO water, what does the pure water taste like?
 
I'm wondering though rockeye if somehow the filter is rigged backwards so that you've accidentally collected the wastewater instead of the RO water. The flow tends to come out evenly between the two lines on mine and if someone swapped the colours over in my sleep I wouldn't know. Test your RO water pH and it should be a bit less than your tap water pH. Taste both and it should be clear which is which.
I've never heard of adjusting pH post boil but some elitist brewers may do it for fermentation reasons I'm not aware of. Best to get pH right during the mash using brewing salts as suggested or some form of acid (citric or lactic are common). Obviously there has to be a balance so that the right profile is hit for taste and mashing.
 
wynnum1 said:
RO water is not suitable for drinking if all the salts and minerals are removed when they recycle water calcium has to be added to the water to stop the water from dissolving concrete.
you might want to to tell the navy and all those cruise ship companies.
personally i found that you just kept drinking it and it never slaked the thirst.
 
wynnum1 said:
Add some brewing salts and some minerals
If it's just pH you want to drop, you'll have more success using food grade acid before flavour levels are detectable.
 
Yeh I use the ez water sheet to calc mineral, acid additions predicted mash ph etc.

The waste line was connected then I got the filter with a sticker on it saying waste line, so it's unlikely I'm collecting waste water for my brews, Just to be sure I might collect some waste water and measure tds, guessing it should be way higher tds.

Thinking of doing a 25l batch with my Ro water and testing mash & boil ph, adjusting if need be, then bitter to 30ibu, see if I can get rid of the harshness.

Found these two articles pretty interesting, and is pushing me towards thinking my water is causing a ph issue.

http://beerandwinejournal.com/proper-boil-ph/

http://braukaiser.com/wiki/index.php?title=How_pH_affects_brewing
 
RO Water even if it has a high ph (usually ~8 from memory) has little to no buffering capability so your grain etc will be able to drop it down with ease. CaCl2 and CaS04 you need for the the free calcium ions which help in the mashing and yeast health etc.

If its just RO water drinking it is fine, try it does it taste like nothing? RO/DI water is bad for you don't drink.

Edit: I have been told you can test the ph of your RO water by adding salt (NaCl), dont put your ph electrode straight in as it will ruin the electrode.
 
barls said:
you might want to to tell the navy and all those cruise ship companies.
personally i found that you just kept drinking it and it never slaked the thirst.
Actually its true if the RO plant has been configured for de-mineralised water. For drinking water you need to run the de-min water through a calcite filter first.

My little RO unit at home is setup for de-min water for making Starsan solutions, but can be changed to make drinkable RO water.

We have problems here at work with the de-min water corroding metal pipes.
 
Say if my mash ph is close to on target @ 5.5ish @ room temp.

I'm aiming for 107L pre boil into my kettle.

Finish sparging with runnings at 1.008.

But only have 67L wort @ 5.5ph in the kettle.

To get to my desired pre boil volume and gravity I have to add 40L of RO water that's @ 7.5 ph.

Isn't the extra 40L of RO water going to dilute the concentration of hydrogen atoms thus raising the ph?
 
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