Topping up with a LOT of water??

[Chrispy92]

Hey guys just a curious question about topping up a batch with a big amount of water.

So lets say you take the grains for a 5.5 gallon batch, and do a full mash with all the ingredients in only 3 gallons of water, boil this 3 gallons etc with all the hop additions etc then at the end of the normal process put the wort into the primary (obviously with a higher OG than the recipe) then add water to bring it up to the full 5.5 gallons, essentially diluting it down to the recipe OG.

My concerns are the effects of a smaller volume of water on conversion efficiency and mash PH, will this considerably smaller volume of water and larger grain bill effect the final beer? Also curious about hop additions and alpha acid extraction?

What are you thoughts?

 

[Gnomebrewer]

Your efficiency will drop (mash efficiency, not conversion efficiency), because you won't have much sparging.
You'll need more hops, because the boil gravity is higher (the higher the gravity, the lower the extraction of bitterness from hops).
Mash pH won't be affected, because the mash doesn't change.
The only other issue I can think of is the potential for scorching with the high gravity boil.
I use this method sometimes to get two kegs worth (40L) out of one batch (I can only boil enough for a 30L batch at one time). But I'm only adding 10L towards the end of the boil to a 40L batch.

 

[wilserbrewer]

Your efficiency will most likely suffer giving you a substantially lower gravity if you top up to the full 5.5 gallons resulting in a lighter watery beer. I would suggest mashing with the maximum amount of water, topping the kettle with water at the end of the mash, and also do a sparge if possible. When finished boiling and chilling, take a gravity reading and then top up the fermenter to be close to the recipe original gravity. You will likely get 4 or 4 1/2 gallons, maybe more maybe less hard to predict....

I wouldn't be overly concerned with hop utilization or other minor aspects, concentrate on the prime objective of extracting as much sugar as you can....make the beer and measure your results and make adjustments on the next batch as you see fit...

 

[Bobby_M]

The effect on the hopping is not really the lower utilization due to the gravity, it's the IBU dilution.

 

[rhys333]

I have done similar things in the past due to being shut up indoors during the depths of winter. A 5 gallon pot can boil 4.5 gallons of wort, as long as you're VERY careful with the hot break. After a controlled boil you can yield 3.5 - 3.75 gallons post-boil that you can just roll with, or do as you're planning and top up to 5 or 5.5. Just be sure to increase your flavor hops a little to compensate for the dilution. If mash efficiency is a concern, maybe plan for something like 5.5% abv and 75% efficiency. That way if you come under, you're still at a decent 4.75 - 5%.

 

[IslandLizard]

Can't you boil in 2 or 3 kettles/pots at the same time to get closer to your 5.5 gallon batch size?

Or boil 2x back to back. Only one prep, mash, and cleanup.

 

[Chrispy92]

I have one large 19L pot which means I can do a max boil of around 17L, down to 15L after boil off.

I do have two smaller 7L pots I could boil at the same time but how helpful would this be? Could I sparge the grains into these smaller pots and have multiple worts boiling? Adding hops to only the big one?

Not sure how I could work it to minimise the amount of top off water

 

[chickypad]

I occasionally brew 3 gal of wort and top off to 5 gals, but for the reasons others mentioned above I only do it with select brews - namely fairly low gravity, low bitterness brews. I could use a second pot, but I do it this way for simplicity. As far as accounting for the lower efficiency, it's the same as brewing any high gravity brew. If you know your numbers for that it's not hard to plan your recipe.

 

[IslandLizard]

I have one large 19L pot which means I can do a max boil of around 17L, down to 15L after boil off.

I do have two smaller 7L pots I could boil at the same time but how helpful would this be? Could I sparge the grains into these smaller pots and have multiple worts boiling? Adding hops to only the big one?

Not sure how I could work it to minimise the amount of top off water

I'd say your 19L kettle (~5 gallons) could comfortably boil 15-16 liters (~4 gallons) and perhaps a little more, still leaving adequate headspace (3-4 liters, ~1 gallon) to prevent boil overs during surges.

Use one or both of your smaller pots to boil the 2nd and/or 3rd runnings down while you boil the large kettle.

While you're boiling off wort during the hour, replenish the big kettle with the content from the small pot(s) to keep it around that 15-16 liter mark. Add your hops to the big kettle.

At the end of the boil, while you're chilling, combine as much as you can from the small pot(s) without overflowing, and fill your fermentor. On the side, you can easily chill whatever is left in the small pot(s) by putting them in a sink or small tub with cold water. Add that to your fermentor too.

You may need to compensate for some extra boil off using 2 or 3 pots instead of one, but you should be close to your intended volume and OG, without sacrificing hop extraction and diluting your beer. After 2 batches you'll have all those variables figured out.

I have an 8 gallon kettle and for 5.5-6 gallon batches I do the same, boiling down 3rd runnings in a smaller pot, since the kettle is a bit too small to contain the whole pre-boil volume without splashing sticky wort all over the place.

 

[Chrispy92]

I'd say your 19L kettle (~5 gallons) could comfortably boil 15-16 liters (~4 gallons) and perhaps a little more, still leaving adequate headspace (3-4 liters, ~1 gallon) to prevent boil overs during surges.

Use one or both of your smaller pots to boil the 2nd and/or 3rd runnings down while you boil the large kettle.

While you're boiling off wort during the hour, replenish the big kettle with the content from the small pot(s) to keep it around that 15-16 liter mark. Add your hops to the big kettle.

At the end of the boil, while you're chilling, combine as much as you can from the small pot(s) without overflowing, and fill your fermentor. On the side, you can easily chill whatever is left in the small pot(s) by putting them in a sink or small tub with cold water. Add that to your fermentor too.

You may need to compensate for some extra boil off using 2 or 3 pots instead of one, but you should be close to your intended volume and OG, without sacrificing hop extraction and diluting your beer. After 2 batches you'll have all those variables figured out.

I have an 8 gallon kettle and for 5.5-6 gallon batches I do the same, boiling down 3rd runnings in a smaller pot, since the kettle is a bit too small to contain the whole pre-boil volume without splashing sticky wort all over the place.

I meant to write and thank you for this Isalnd Lizard. Methods worked a charm for a pale ale I did two days ago and I'm about to do a step mash wheat beer the same way and hopefully it all comes together again.

Hit my numbers pretty well!

Cheers