Return to TheElectricBrewery.com
  [ Shop ]   [ Building ]   [ Using ]   [ Recipes ]   [ Testimonials ]   [ Gallery ]   [ FAQ ]   [ About Us ]   [ Contact Us ]   [ Newsletter ]

Log inLog in   RegisterRegister   User Control PanelUser Control Panel   Private MessagesPrivate Messages   MembershipClub Memberships   SearchSearch   MemberlistMemberlist   Photo AlbumsPhoto Albums   Forum FAQForum FAQ


Boil off rates for 5 gallon batch

 
Post new topic   Reply to topic   Printer-friendly view    TheElectricBrewery.com Forum Index -> Using Your Brewery
View previous topic :: View next topic  
Author Message
motorbear25




Joined: 12 Oct 2017
Posts: 7



PostLink    Posted: Sat Sep 11, 2021 6:03 pm    Post subject: Boil off rates for 5 gallon batch Reply with quote


        Register to remove this ad. It's free!
I have completed four batches on the system and I have encountered a consistent issue. During the sparge process, I collect a volume of wort in the boil kettle as outlined in the "Brew Day step by step" as follows:

"Since we want end up with 12 gallons after the 1.5 hour boil used by this recipe, we must collect 12 + (1.5 * 1.9) = 14.9 gallons of wort in the Boil Kettle. (A 60 minute boil would require us collecting 13.9 gallons, a 120 minute boil 15.8 gallons)."

I have adjusted the variables for my batch size (5 gal) and boil time and have used the 1.9 gallon/hr variable. I start my boil time when the panel indicates 211 deg. My last batch was a 90 minute boil with the intent to collect 5 gallons in me fermenter. 5+(1.5*1.9)= 7.85. I transferred 8 gallons into the boil kettle. Upon transferring to the fermenter via a northern brewer ss counterflow chiller, I was only able to get just about 4 gallons. This has happened several times and I'm wondering where my error is.

I'm wondering if the formula should include the small amount that remains in the chiller, pump, and hoses and some of the liquid that remains in the boil kettle that can't be removed (not too much). Or is the boil off rate different for the small volumes of liquid based on where the element is positioned in the kettle.

Is there a different formula to use for 5 gallon batches or am I missing something? I know the instructions are for a much larger batch but only want to make small batches while I gain proficiency on the system and brewing in general.

Thanks!
-Matt
Back to top
kal
Forum Administrator



Joined: 12 Dec 2010
Posts: 11116
Location: Ottawa, Canada

Drinking: Pub Ale, Electric Creamsicle, Mild, Pliny the Younger, Belgian Dark Strong, Weizen, Russian Imperial Stout, Black Butte Porter


PostLink    Posted: Sat Sep 11, 2021 6:18 pm    Post subject: Re: Boil off rates for 5 gallon batch Reply with quote

Hi Matt,

For best flavour and long term stability I like to boil hard which results in a reasonably high boil off rate of 1.9 gallons per hour for my 12 gallon (post-boil at @68F) batches. But that doesn't mean everyone else will have the same boil off rate or even want the same boil off rate.

Boil off rate will vary based on kettle geometry (kettle height vs width ratio, batch size, environment (humidity levels, temperature, wind, etc), how hard you boil, how long you boil, and so forth. Run at the boil vigorousness that you like and measure the before and after amounts in your kettle to get your boil off rate per hour for your setup and then use it in future calculations. If you brew outdoors where temperature/wind/humidity varies it will also change your rate even if everything else is the same (one reason why I like to brew indoors as it helps ensure consistency). When measuring volumes make sure to measure at the same temperatures too since hot liquid expands. For example, with my 12 gallon batches sizes the volume is ~12 gallons at room temp and ~12.5 gallons at boiling.

The amount you actually get into your fermenters is completely different and has other losses involved from the things you mentioned like pumps, hoses, etc. Even having lots of hops in the boil will soak up wort. Brewhouse efficiency calculators can be used to figure this out but I don't bother. I just (usually) always make enough wort to have 12 gallons post boil (at 68F) because for me it accounts for my various post boil losses like hop absorption, chilling / fermentation sediment, racking / kettle / hose deadspace, etc. All so that by the time I keg, I get two 5 gallon kegs completely full. If I'm brewing a beer that doesn't have a lot of dry hops I'll sometimes make 11 gallons instead. If there's a bit extra, I just dump it (or sample it Wink ) at kegging. Wort/beer is cheap so I'd rather always have too much than too little and don't mind dumping a bit.

Good luck!

Kal

_________________
Our new shop with over 150 new products: shop.TheElectricBrewery.com
We ship worldwide and support our products and customers for life.
Purchasing through our affiliate links helps support our site at no extra cost to you. We thank you!
My basement/bar/brewery build 2.0
Back to top
View user's photo album (21 photos)
motorbear25




Joined: 12 Oct 2017
Posts: 7



PostLink    Posted: Sat Sep 11, 2021 6:40 pm    Post subject: Reply with quote

Thanks for a great reply!
I brew in a garage (someday indoors I'm hoping) and it has been warm. The environmental factor is obvious and I didn't consider that. My system was built using your specs and equipment exactly with the exception of the pumps (Blichmann). My first attempts have been blonde ales and a czech lager.

I think the biggest takeaway is doing a test. Then instead of calculating for 5 gallons, calculate for 6 or 6.5. I think that would give me the volume I'm missing. I'm thinking this may closely emulate your calculations for 12 gallons with the goal of 10 gallons in your kegs.

Thanks again!
Back to top
kal
Forum Administrator



Joined: 12 Dec 2010
Posts: 11116
Location: Ottawa, Canada

Drinking: Pub Ale, Electric Creamsicle, Mild, Pliny the Younger, Belgian Dark Strong, Weizen, Russian Imperial Stout, Black Butte Porter


PostLink    Posted: Sat Sep 11, 2021 7:54 pm    Post subject: Reply with quote

Sounds reasonable and you’re welcome. Happy brewing!

Kal

_________________
Our new shop with over 150 new products: shop.TheElectricBrewery.com
We ship worldwide and support our products and customers for life.
Purchasing through our affiliate links helps support our site at no extra cost to you. We thank you!
My basement/bar/brewery build 2.0
Back to top
View user's photo album (21 photos)
Display posts from previous:   
Post new topic   Reply to topic   Printer-friendly view    TheElectricBrewery.com Forum Index -> Using Your Brewery All times are GMT
Page 1 of 1
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum



Forum powered by phpBB © phpBB Group