Adding RO water during/after fermentation?

HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.

Help Support Homebrew Talk:

luckybeagle

Making sales and brewing ales.
Joined
Apr 30, 2018
Messages
398
Reaction score
89
Location
Springfield, Oregon
My efficiency on a Dry Irish Stout was a little too good and I ended up with a preboil gravity of 1.044, which is actually my target OG! I'll need to dilute it with about 1.25 gallons of water to bring it back down to where it belongs.

I wouldn't be able to add it until during or after fermentation (system is disconnected and I'm short on time). Just wondering if RO is "pure" enough to not worry about infection with a 1.25 gallon water addition. Can I use RO water for this without boiling or reconstituting with my brewing salts?

Thanks
 
Last edited:

mattdee1

Supporting Member
HBT Supporter
Joined
May 15, 2015
Messages
682
Reaction score
405
You can probably dilute it down with no issues but it seems like you'd just be introducing opportunities for things to get screwed up, for questionable benefit.

I guess my point is, it's homebrew... who cares if you miss your target? Just roll with what you have and if you want lower gravity adjust the recipe/process next time to compensate.
 

danimal92sport

Undefeated at naps
Joined
Jan 28, 2020
Messages
173
Reaction score
353
Location
Midwestern US
I’ve diluted with RO water after the boil just before pitching. I used a sanitized pitcher but non-boiled water out of my RO system. There’s some risk, but mine have been fine.
 

NTexBrewer

Supporting Member
HBT Supporter
Joined
Feb 19, 2013
Messages
951
Reaction score
355
Location
Just North of Dallas
Isn’t this what we all did when we started Extract Brewing?? Adding top-off water after the boil.

I would have no problems adding RO water at the start of fermentation. But it looks like you are planning to add the water post or during fermentation. If this is the case then I would bring that water up to a simmer and then chill it before adding.

Do you keg or bottle condition? If you keg you can add the hot water to your keg and then chill it in your keezer. If you bottle condition this will be your sugar water addition and you may not have to chill it that much if you cold crash your beer.
 

Steveruch

Well-Known Member
Joined
Nov 15, 2016
Messages
1,575
Reaction score
773
Location
Crescent City
My efficiency on a Dry Irish Stout was a little too good and I ended up with a preboil gravity of 1.044, which is actually my target OG! I'll need to dilute it with about 1.25 gallons of water to bring it back down to where it belongs.

I wouldn't be able to add it until during or after fermentation (system is disconnected and I'm short on time). Just wondering if RO is "pure" enough to not worry about infection with a 1.25 gallon water addition. Can I use RO water for this without boiling or reconstituting with my brewing salts?

Thanks
What was your O G? There's no reason a dry Irish stout can't be a bit stronger.
 
OP
luckybeagle

luckybeagle

Making sales and brewing ales.
Joined
Apr 30, 2018
Messages
398
Reaction score
89
Location
Springfield, Oregon
Thanks everyone! I will leave it as-is. The OG was 1.052. It'll be called an export stout, and that'll be just fine.

I keg. If it tastes too bold, I can dilute down with boiled RO, but I think it'll be OK.

Sometimes I get so hung up on the BJCP guidelines that I forget we're homebrewers and we'll often be off by a few points in either direction--sometimes more. Also I'm trying to keep in mind that commercial examples occasionally breach BJCP guidelines (I'm pretty sure the Westmalle Tripel is outside the guidelines on OG/ABV by 15% on both, yet... they... created the tripel). Heck, I had a Munich Helles this afternoon that was 6% ABV--which is about a half a point higher than the upper limit for the style. I think as long as the BU:GU is in check, and care was put into fermentation/water/process/etc, it'll be good.

Another example of me needing to RDWHAHB.
 
Top