1st Ag (biab)

[Diesel80]

Well,

have not long finished the boil and cubing of my first BIAB AG.

It was a long to but fun brew day. Topped out at 7 hours grain to cube!

Smell was awesome, efficiency was very poor. 50% according to brewmate.

Not going to beat myself up over the numbers but i am curious about the IBUs of the final product.

My Kettle:
80L Alu pot 500mm diameter

Heat:
3 ring cast iron burner
2400w Element (once boiling this was only thing running).

My receipe was:
5.7kg of marris otter
0.15kg Caramunich
0.05kg Carafa 2

Challenger 4.5% 25g 60min
Challenger 4.5% 25g 30min
Challenger 4.5% 10g 10min + whirlfloc
Challenger 4.5% 5g 0 min

Strike water 35L

Mash time 60 mins (doughed in at 69, gave it a pump with paint stirrer, lagged kettle and checked and stirred once during mash).
Mash temp was 66 after grain addition - according to my slow ready thermometer, was 64-65 at 60mins).
Bag out and onto a rack over kettle to drain, squeezed it, and put 4 or so litres of water boiled in kettle through it.

Kettle level was about 35L at start of ramp up to boil.

Boil time 90 mins (35 mins from bag out to boiling).

Strike water 35L, target batch volume into fermenter was 27 @ 1.050.
Actual into cube for no-chill was ~20-21 @ SG 1.048.

Couple of questions for the Pros:
1) Am i likely going to have a really bitter brewski on my hands here?
2) Why was my extraction so low i wonder? My grain was crushed with a ghetto mill (pasta maker), but despite taking an eternity grain looked crushed. When bag was lifted out, wort looked well like wort. good colour in it, smelt like i was making beer too.

Oh well i will get some pics up tomorrow when i recover from this epic adventure.

look forward to some advice on how i can get better extraction. Also i have epic evap rate so how do i factor that in going forward?


Cheers,
D80.

 

[ekul]

First of all, congrats on your first brew!


I put your brew through brewmate and it says it is going to be 34IBU with nochilling. So thats not too bitter at all.

How did you measure you OG? You may have a higher og than expected if you measured the wort hot with a hydrometer.

If you measured the gravity correctly then the thing i would look at would be the crush. If you are buying your grain from a LHBS they usually offer to crush the grain for you if buying in small amount. Maybe do that once so that you can compare the crush, or do a search on here for a pic.

And don't worry about it taking so long. The easiest way to shorten a brewday is to do bigger batches! And you have an 80L pot so you'll be doing doubles in no time.

 

[yum beer]

well done diesel,

I think youll find that with your 80 litre pot you will get a fair amount of boil off due to the large surface area, as you say pot is 500mm diameter,

maybe look at doing double batches to reduce the percent of boil off or go for a smaller pot for your kettle, 350mm diameter to reduce boil off.
Or just add an extra 1-1.5kg of grain to your mash and go for higher gravity to water down. you have the figures to use in brewmate now to work it out.

 

[Diesel80]

I put your brew through brewmate and it says it is going to be 34IBU with nochilling. So thats not too bitter at all.

How did you measure you OG? You may have a higher og than expected if you measured the wort hot with a hydrometer.

Hi Ekul,

Does the fact that i ended up with ~7L less in the cube have an impact on IBUs? Is there a direct ratio? I used the amount of hops in the receipe above and was shooting for 27L with it, only got 20. So was wondering if i have ended up with (27/20 * 34) IBUs.

OG was measured using a bit of wort out of the siphon hose into hyrdro tube. Went in hot but was 20 odd degrees once floaties had settled.

 

[Silo Ted]

When I do BIAB, I calculate to have 27l at the end of the boil. This fills a 20L cube perfectly (maybe the capacity is 22-23L, who knows) without tipping my kettle - ie it stops at tap level.

Next time, measure the volume left behind as well.

When you calcuate a recipe, wok it out on both the cube volume + the left over wort/trub/hop snot combined.

As long as you find a system and stick to it the same each time, and record measurements, you will get better beers out the other end.

 

[Diesel80]

When I do BIAB, I calculate to have 27l at the end of the boil. This fills a 20L cube perfectly (maybe the capacity is 22-23L, who knows) without tipping my kettle - ie it stops at tap level.

Next time, measure the volume left behind as well.

When you calcuate a recipe, wok it out on both the cube volume + the left over wort/trub/hop snot combined.

As long as you find a system and stick to it the same each time, and record measurements, you will get better beers out the other end.

Cheers ted for the pointers. I guess everyones system and setup is slightly different. I will take the advice and make sure i employ a system whereby I measure boil start more accurately and end boil vol as well. FWIW after i tipped the cube into fermenter about 20 mins ago i had 19L into the fermenter and about 1L of crud left in cube.

Just pitched the yeasties in after giving them a bath. In danstar nottingham we trust!

Cheers,
D80