Deionized Water for homebrewing...thoughts?

[kdreese]

So let me preface this with this being a conversation/question thread on theory and maybe not real life practice.

I am wondering what others opinions are on utilizing deionized water for homebrewing.

Let me explain... I was at work talking about deionized water and the process it uses to remove (in theory) everything but the H2O molecules from the water. Wouldn't it be great to start with a blank slate with brewing water. Then add in what we want to match a specific water profile. This would also be to ensure consistency in each batch. Essentially we would prepare our water much like a grain bill. X # of gallons, X oz of calcium, etc.

Being a purist and an rookie water nerd I want to stop many of the comments with this. Deionized water IS NOT the same thing as distilled or RO water. Many of the ionic molecules in water will evaporate with the distilled water at very low temps. The best way we know to remove almost everything is through Deionizing filter (bead).

Would it have application to the brew day, can we add back in (at specific quantities) the minerals we want, would this help estimate mash pH?

I did a quick search on deionizing filter and they are no worse than RO. I do not know what capabilities specific filters have or if commercial filters can produce deionized water at the level which labs require but its a theory?

Any thoughts? And to be clear I would in theory want to add minerals back in and not use only the H2O since the molecular compounds and minerals in water give the beer specific taste. I should also know I have no chemistry experience passed the basic college class levels and only nerd out on water because its important for beer, I was a certified pool operator, and I enjoy some chemistry. Who knows, maybe we can put together enough thoughts and I can purchase the filter and run some tests and make an article for the site. Thanks y'all!

 

[z-bob]

For our purposes, distilled, RO, and DI water are functionally equivalent. No significant difference.

 

[agrazela]

I use (ok, steal) DI from the lab, cut it with tap to get some micro amounts of beneficial ions, then build with salts. Also "borrowed" from the lab.

 

[kdreese]

agrazela-So you obviously work in a lab setting. Do you think there is a significant difference in RO vs DI? also how long in advanced do you prep your water and do you change your additives based on the brew or just use the same water each time?

 

[kdreese]

I know on a macro level and for home brewing they are functionally equivalent but in theory???

 

[agrazela]

For brewing, likely no significant difference between DI, RO, distilled, etc. Once you throw salts, malt, etc. in there, and especially if you do cut with some tap water, any differences there might have been are almost certainly dwarfed.

For something like a Pale or IPA, I usually find myself cutting about 50:50 with my Alvarado District water. For stouts, porters and such more like 60:40 DI:tap. For something like a Kolsch or lager, more like 80:20 DI:tap.

I'll put all my water in the brew kettle (I do no-sparge, thin mash BIAB), add sodium metabisulfite (0.04g/gal of tap) to kill the chloramines, wait 15-30 min, add the salts and any acid, then get right to heating.

And yes I do alter the salts and acid additions based on the brew. I use Bru'n Water for this, and for pales and IPA's I typically target the "Pale Ale" profile, for stouts and porters one of the "Brown" profiles, and for lagers one of the "Yellow" profiles. I have found it to be quite accurate against my (also borrowed) pH meter, my mash pH is never off of predicted by more than 0.1 unit.

 

[kdreese]

Nice, I have not reached that level yet. I do All-grain and have not invested the time yet to change around my water profiles but its coming. First I want a solution to not purchasing water. Do you think charcoal filters will remove enough of the chlorine/chloramines? Having a background in pool chemistry I never attempted to remove chlorine, just minimize chloramines but i know most city waters use chloramines over chlorine since it is more stable in the water. I have not even sent off my water from the tap in Philly to see what an "average" test would look like. But that is on my to-do. I hate lugging water jugs from the store.

 

[z-bob]

I'm still using RO water from the grocery store for brewing (someday I'll learn how to dealkalize the local water with slaked lime) but I use tapwater for other things like yeast starter. I use vitamin C to remove the chloramine.

 

[The10mmKid]

I also 'borrow' RO and DI water from work. (Plating lines)

I use RO for extract brewing.

I cut it 50/50 with carbon filtered fridge water for everything else.

At work, we carbon filter the municipal water, then it goes through the RO system, and then through the DI bead columns.
Most cleaning and etching tanks use the RO, all rinse tanks use DI.

I can't speak of the purity other than the simple test us maintenance guys make. They wont let us play with their expensive calibrated Lab toys.

We test by conductivity.
City ~ 650 uMhos
Ro ~ 6 uMhos
DI ~ 0 uMhos

'da Kid

 

[FuriousE]

Check out the Brew Science forum. Lots of great info on building water from RO or DI sources.

 

[Flakk]

I also "borrow" water from work (microbiology lab). We recently installed a $250k system based off of systems used in the semiconductor industry, and the specs on it are amazing. We test conductivity, TOC, and micro on a daily basis.

 

[Foosier]

Nice, I have not reached that level yet. I do All-grain and have not invested the time yet to change around my water profiles but its coming. First I want a solution to not purchasing water. Do you think charcoal filters will remove enough of the chlorine/chloramines? Having a background in pool chemistry I never attempted to remove chlorine, just minimize chloramines but i know most city waters use chloramines over chlorine since it is more stable in the water. I have not even sent off my water from the tap in Philly to see what an "average" test would look like. But that is on my to-do. I hate lugging water jugs from the store.

Before you do anything expensive like consider buying a whole house filter, figure out what your tap water is giving you. Your water may be fine almost as-is. If you do a search on this site for "water report [your town]" you will likely find someone hjas already posted one. It may not be exact, but it is close enough to give you an idea where you are starting from.

I did this and found my city water was just fine for brewing as long as I did 2 things. 1 - neutralize the Chloramines with camden. 2 - neutralize the naturally high akalinity with phosphoric acid. With these 2 simple and to be honest CHEAP changes, I can avoid buying water. We are talking about pennies per batch because camden and the acid are cheap and you use very small amounts.

 

[kdreese]

I need to get the test done. But I don't trust phillys water to much. If there water department is run like anything else in the city then who knows what actually is in it. I would never buy a wolle house filter. Though I own my house I'm in the military so I want something portable. Should be interesting when u come up with something. But short teem goal is to send off a water test this weekend!

 

[jerrya100]

My opinion would be to use the RO water as the RO would remove all the unwanted minerals. Deionized water depending on what is used as the mineral to swap ions could leave unwanted minerals. For example If a home water softener is used, salt is used to swap the minerals. You would end up with a lot of sodium in your water.