BIAB Newbie - water / grain ratio questions :)

[ultrashock]

Hello,




I have more than 30 batches, but all of them with 3 vessel equipment.



One day I decided to turn into BIAB brewing - because of less equipment to clean and easier process and less time. I also have built RIMS with 3kw heating element, which i can use for heating the mash and keep the temperature during mash.



I have the following questions:



1. Usually i do BIAB with a little sparge water (20 liters - the size of the plastic bucket where I heat the sparge water). My kettle is 100 liters and I have very good bag for it. My question is what is the should be water to grain ratio(liters/kg), with these 20 L



2. What should be water to grain ratio for typical BIAB with no sparge no sparge?



Please if you can give me ratios in metric, otherwise is very difficult to calculate.


Thnaks!

 

[McKnuckle]

Because classic BIAB is a full volume mash technique, we tend not to consider the water:grain ratio at all. It just "is what it is" to produce the recipe on a given system.

If you are sparging due to lack of available mash space or because of an efficiency improvement, just withhold a convenient volume of water for your system, and don't worry about the ratio.

 

[wilserbrewer]

Most BIAB brewers don’t concern themselves much with water / grain ratios, neither do most batch spargers either I believe.

Best method is to figure “total water required” and either do a full volume mash, or hold some water behind for a sparge.

Opinions and methods vary, big surprise lol.

Some prefer a larger “dunk” or batch sparge to increase efficiency, more so on larger high gravity beers. Others prefer a small “pour over sparge” like a fly sparge as a kettle volume adjustment to meet pre boil volume.

 

[wilserbrewer]

Can’t comment on your 20 liter sparge not knowing your mash volume or strike water volume, or how and why you sparge?

 

[RM-MN]

You don't need to heat the sparge water unless you start with ice. Cool water added to the hot, wet grains quickly warms up and does nearly the same job as hot water.

I don't worry about the water to grain ratio, I worry about how much water I can start with without running over when I add the grains because I'm starting with a kettle that is too small. When the mash is over I pull the bag of grains and sparge to make the kettle as full as I dare before boiling.

 

[jpakstis]

Yeah just like everyone else I don’t concern myself with ratios. I “start” with my anticipated volume I want in the fermenter and work backward. And honestly I just guesstimate since I’m not a stickler for precision. The only two things I need to know is my boil-off rate and the grain absorption rate (which for me is pretty low since I squeeze that bag like it owes me money)! I usually make IPAs in the 7-8% ABV range and I usually prefer about 6ish gallons going into the fermenter so I start with around 8 1/2 gallons of water.

I also don’t do any sort of sparge but when I did, I didn’t worry about heating it up. My understanding is that sparging is mainly to rinse the residual sugars from the grain so it doesn’t matter what temp it is. The only benefit to heating it is so that the pre-boil volume will already be hot and won’t take as much time to heat to boiling temps.

But if you do a full volume BIAB mash you don’t have to worry about that because the entire volume is already at the same temp.

 

[LittleRiver]

What I do is use the Priceless BIAB Calculator to determine my total water volume. I like that calculator because in addition to gallons it gives depth measurements based on the dimensions of your kettle. The calculator will give you more information that you really need, but it's easy to pick out the bits you do need. You can select metric or imperial units.

I never worry about grain/water ratio. I usually don't sparge, but if I do it's done this way:

• mash with 1/2 of the water
• drain the wort into a bucket -- leave the bag and grains in the kettle
• add the second 1/2 of water to the kettle and stir
• hoist the bag and immediately turn on the heat -- let gravity drain the bag into the kettle during the boil
• pour the bucket of wort into the kettle

To me that's the simplest and least messy way of conducting a BIAB sparge. There's never a need to handle a drippy wet bag of grains (as in a dunk sparge). It's less tedious than slowly pouring water over a suspended grain bag (as in a pour over sparge).

 

[soccerdad]

I'm a bit confused. With a 100L kettle and bag to match, why sparge? I would think that you could make 10 gallon (40L) batches with a Full Volume Mash and no sparge. Plus, if you are doing a 40L batch, you are likely to use 10kg or more in grain. So with a dunk sparge, you likely could not fit the grain in the 20L kettle to rinse it. Are you looking to boost efficiency to add the sparge step?

 

[LostHopper]

Yeah just like everyone else I don’t concern myself with ratios. I “start” with my anticipated volume I want in the fermenter and work backward. And honestly I just guesstimate since I’m not a stickler for precision. The only two things I need to know is my boil-off rate and the grain absorption rate (which for me is pretty low since I squeeze that bag like it owes me money)! I usually make IPAs in the 7-8% ABV range and I usually prefer about 6ish gallons going into the fermenter so I start with around 8 1/2 gallons of water.

I also don’t do any sort of sparge but when I did, I didn’t worry about heating it up. My understanding is that sparging is mainly to rinse the residual sugars from the grain so it doesn’t matter what temp it is. The only benefit to heating it is so that the pre-boil volume will already be hot and won’t take as much time to heat to boiling temps.

But if you do a full volume BIAB mash you don’t have to worry about that because the entire volume is already at the same temp.

my thoughts exactly

 

[ultrashock]

Ok, I understood. No worries about ratio, just calculate the target volume, keep in mind the BOIL EVAPORATION RATE, GRAIN AND HOPS ABSORPTION and any other loses. If a fly sparge for example, just to remove the amount and that's it.

wilserbrewer- my kettle is 100 liters and i usually make about 50-55 liters beer (this is the amount in fermenters). Usually I make beers between
soccerdad - yes, my purpose is boosting the efficiency, that's why I sparge as much as can.

In fact, is there any reason to sparge and does this sparging give more efficiency? Because otherwise it's much easier not to sparge, and put all the water in the kettle (I have enough space)

 

[doug293cz]

...

In fact, is there any reason to sparge and does this sparging give more efficiency? Because otherwise it's much easier not to sparge, and put all the water in the kettle (I have enough space)

Yes, sparging always increases efficiency compared to not sparging when pre-boil volumes and grain absorption are equal. An optimal single batch sparge will give about 8 percentage points higher lauter efficiency (and therefor mash efficiency, since mash efficiency = conversion efficiency * lauter efficiency) than a no sparge process, all else being equal.

An optimal batch sparge can be obtained when the first runnings and sparge runnings are about equal volume. This implies sparge water volume equals pre-boil volume / 2, and strike water volume equals sparge water volume + total grain absorption. With your vessel volumes, it would be difficult to get your sparge volume that high, so the best you can do is the maximum sparge volume you can handle.

Brew on

 

[ultrashock]

One simple calculation for my equipment. If I want to make a beer 13P (or 1.0526), the calculator shows that I will have 54L beer with 12kg Pale Ale malt.

If I have 20L bucket for sparging, I boil 60min and I have about 4 Liters per hour boil off rate, 1:1 grain absorption (1 liter absorb 1kg of grain) and 2 liters kettle loses (sediment, dead space etc.), that means that I have to use:

54(amount of beer in fermenter) + 12(grain absorption) + 4(boil-off) + 2(kettle loses)-20(sparge water) = 52 liters for mash.

Is the calculation correct?

 

[FunkedOut]

In fact, is there any reason to sparge and does this sparging give more efficiency? Because otherwise it's much easier not to sparge, and put all the water in the kettle (I have enough space)

As doug293cz stated above, sparging does increase effeciency. If it’s effeciency you’re chasing, you will peak that parameter when the volume you leave in the kettle matches the volume you leave in the sparge. You can leverage the research on batch sparging, as that is effectively what you’re doing.

(Strike Water) = (Grain Absorption) + (Half of the Pre-Boil Volume)

(Sparge Water) = (Half of the Pre-Boil Volume)

But your OP states that you turned to BIAB to to clean less, a simpler process and to save time. If that’s what you’re chasing, add the extra dollar worth of grains and live out your dreams.
I’ve heard it said that as effeciency increases, wort quality decreases. You might find you really like the beer made from 70% effeciency wort over 90%?

 

[doug293cz]

One simple calculation for my equipment. If I want to make a beer 13P (or 1.0526), the calculator shows that I will have 54L beer with 12kg Pale Ale malt.

If I have 20L bucket for sparging, I boil 60min and I have about 4 Liters per hour boil off rate, 1:1 grain absorption (1 liter absorb 1kg of grain) and 2 liters kettle loses (sediment, dead space etc.), that means that I have to use:

54(amount of beer in fermenter) + 12(grain absorption) + 4(boil-off) + 2(kettle loses)-20(sparge water) = 52 liters for mash.

Is the calculation correct?

The calculation is correct, but...

If your sparge vessel has a 20L capacity, and contains 20L of water, you won't be able to place the bag of grains into the water without a lot of spill over. The grain is going to contain the 12L due to absorption, plus the volume of the grain itself (about 8L prior to mash, not sure how much volume is lost in mash), so you have pretty much zero room for sparge water in you sparge vessel. Looks like you would need at least a 40L sparge vessel for the batch sizes you are contemplating. Full volume mash with no sparge appears to be your best option.

Brew on

 

[ultrashock]

Ok, thanks for the answers!