Grainfather sparge questions

[beer8360]

Hi All

I am using the grainfather for a hoppy apa. I have 6 kg of grain so its 6 x 2.7 + 3.5 so I get 19.7L of water to start with. I am having difficulty calculating the sparge water could anyone help me in this ?

 

[Ghillie]

Hi All

I am using the grainfather for a hoppy apa. I have 6 kg of grain so its 6 x 2.7 + 3.5 so I get 19.7L of water to start with. I am having difficulty calculating the sparge water could anyone help me in this ?

I use a Robobrew which essentially the same.

I need a pre-boil volume of 28L for 23L into the fermenter. This accounts for ~4L/hr boil off rate; and 4% cooling shrinkage. You should also be there or there abouts.

Your grain will absorb somewhere close to 1L/kg.

So:

19.7L - (6kg x 1L) = 13.7L **This is the volume of wort left in the vessel when you pull the malt pipe full pf grains out**

28L - 13.7L = 14.3L **This is your sparge water volume to get you to 28L.

28L -4L = 24L **Volume at the end of boil**

24L x 96% = 23.04L **4% cooling shrinkage**

Your boil off rate may be slightly different, no way to know without a little trial and error.

To make things easier, forget calcs for strike water and use 18-20L regardless.

So then your sparge amount is just 28L - (strike volume - grain bill).

Good luck pal!

 

[Slid]

Hi All

I am using the grainfather for a hoppy apa. I have 6 kg of grain so its 6 x 2.7 + 3.5 so I get 19.7L of water to start with. I am having difficulty calculating the sparge water could anyone help me in this ?

I would use 35-36L in total, depending on grain volume. As 6kg is a lot, go for 16L sparge.

 

[Justin Dean]

I recommend using the grainfather app calculator for grainfather brews and that will give you the answer

35L brew with 6 kg and 60 min boil is 19.7L mash 25.1 litre sparge

for 28L (seems like a lot of grain for that) is it is still 19.7 L for mash but 18.1L for sparge

Also consider holding 5 l of sparge back and so you can liquor down more accurately to your target SG