How much water to use

[BrewingWisdom]

Hi
I just want to get rid of confusion.
If a 5-liter beer recipe calls for 1 kg of malt. Does that means I have to put 5 liters of water initially for the saccharification rest and later wort boiling? Or I have to put more water to allow for the evaporation and exactly how much more for a 5 liter recipe?

 

[VikeMan]

For a 5 liter batch, you will need more than 5 liters of total water.

Here is the total amount of water you will need:

Desired batch size into the fermenter
+ grain absorption
+ unrecoverable mash tun dead space
+ tun to kettle transfer losses
+ kettle hop/trub absorption
+ boil off
+ kettle to fermenter transfer losses.

Some of the above may not be applicable, depending on your equipment and process. Also, depending on your preference (and possibly your equipment), you can...

- Do a full volume mash, i.e. use all the water in the saccharification rest, -OR-
- Mash with a portion of the water, adding the rest after the sacch rest, either to "mash out" (i.e. bring the mash up to about 170F), or to sparge with.

 

[BrewingWisdom]

For a 5 liter batch, you will need more than 5 liters of total water.

Here is the total amount of water you will need:

Desired batch size into the fermenter
+ grain absorption
+ unrecoverable mash tun dead space
+ tun to kettle transfer losses
+ kettle hop/trub absorption
+ boil off
+ kettle to fermenter transfer losses.

Some of the above may not be applicable, depending on your equipment and process. Also, depending on your preference (and possibly your equipment), you can...

- Do a full volume mash, i.e. use all the water in the saccharification rest, -OR-
- Mash with a portion of the water, adding the rest after the sacch rest, either to "mash out" (i.e. bring the mash up to about 170F), or to sparge with.

So what's your advice on how much water should I use for a 5-liter batch?

 

[VikeMan]

So what's your advice on how much water should I use for a 5-liter batch?

I don't have enough information to tell you that.

Desired batch size into the fermenter = 5 liters

+ grain absorption -> maybe 0.12 gallons per pound of grain. maybe 0.08 gallons/pound if you are doing Brew-In-A-Bag and squeeze the bag while draining.

+ unrecoverable mash tun dead space -> whatever your unrecoverable mash tun space is, if any. If you're doing Brew-In-A-Bag, it should be 0.

+ tun to kettle transfer losses -> whatever amount of wort you lose when you transfer from the mash tun to the kettle (i.e. pump/line losses). If doing Brew-In-A-Bag, it should be 0.

+ kettle hop/trub absorption -> maybe 0.025 gallons per ounce of pellet hops.

+ boil off -> whatever amount of water your equipment boils off during the boil.

+ kettle to fermenter transfer losses -> whatever amount of wort you lose when you transfer from the kettle to the fermenter (i.e. pump/line losses and/or unrecoverable kettle dead space). If you have a kettle dead space and the boil hops sit in that deadspace after transfer, be sure not to double count the hop absorption amount as kettle dead space.

 

[hotbeer]

1 kg of malted grain or 1 kg of malt extract? Extract I know nothing about. At least very little.

Maybe your other mention of saccharification rest should lead me to assume malted grain, but I don't know if that's a thing for extract or not since I don't know much about extract except what it is.

 

[BrewingWisdom]

1 kg of malted grain or 1 kg of malt extract? Extract I know nothing about. At least very little.

Maybe your other mention of saccharification rest should lead me to assume malted grain, but I don't know if that's a thing for extract or not since I don't know much about extract except what it is.

1 kg of malted grain(crushed).

 

[Elric]

@VikeMan gives a great list of the various things you need to account for. I will add that the best way to determine boil off beforehand is to take the kettle you plan to boil in and fill it with a similar (measured) amount of water to what you are expecting to brew and boil it for one hour. After the hour measure how much water you have left and the difference is roughly your boil off rate (+/- a few percent as water temperature differences will cause a disparity between the measured values). This will vary with each pot and heat source, so you really need to check each time a variable changes. I.e. two different kettles on the same propane burner can have very different boil off rates, and the same kettle on a stove may only get to a weak boil, but a rigorous boil on a propane burner giving two different boil off rates.

 

[RyPA]

I'm still dialing in my system as I am pretty new to full grain. Use your best judgement/estimates to start with and write down your total volume at each point, then adjust the next time around to get what you want.

Lets say you start with 7 gallons for your very first batch

1. Starting water for mashing is 7 gallons
2. After mashing you have 6 gallons of wort in your kettle
3. After boiling you have 5.5 gallons of wort in your kettle
4. After transferring to your fermenter you have 5 gallons of wort
5. After transferring to keg/bottles, you have 4.5 gallons of finished beer

So if you want to end up with 5 gallons of beer at the end, try bumping your starting water to 8 or 8.5 gallons instead of 7, etc. More water will be needed if more grain is in the batch, and assuming your process/equipment is a constant.

 

[BrewingWisdom]

I'm still dialing in my system as I am pretty new to full grain. Use your best judgement/estimates to start with and write down your total volume at each point, then adjust the next time around to get what you want.

Lets say you start with 7 gallons for your very first batch

1. Starting water for mashing is 7 gallons
2. After mashing you have 6 gallons of wort in your kettle
3. After boiling you have 5.5 gallons of wort in your kettle
4. After transferring to your fermenter you have 5 gallons of wort
5. After transferring to keg/bottles, you have 4.5 gallons of finished beer

So if you want to end up with 5 gallons of beer at the end, try bumping your starting water to 8 or 8.5 gallons instead of 7, etc. More water will be needed if more grain is in the batch, and assuming your process/equipment is a constant.

But more water also means more malt required to get the same efficacy .

 

[RyPA]

Yeah I was trying to get at that in the last sentence, adjustments are needed based on the amount of grain in the batch

 

[VikeMan]

But more water also means more malt required to get the same efficacy .

All else being equal, more water will get higher mash efficiency. And after the wort is boiled down to the same final volume, the gravity will be higher than if less water was used.

But if you mean just add more water, but don't boil it away, then although mash efficiency will be higher, the post boil gravity will be lower than if less water was used.

 

[hotbeer]

I use 1.25 quarts of water per 1 pound of grain for most of my mashes. I'll let you convert that to some proper metric ratio.

Then I'll rinse the grains at the end of the mash with clean water from a portion of the water that is to get me to my preboil volume.

Some will do more water per weight of grain. Depends on you and your equipment.

Probably what you need to read up on is mash thickness. Since it gets argued so much by some homebrewers, it's probably more important that just you stay within what your mash tun can handle.

So just pick something and go with it so you can build experience.