Cpa Tin And Partial Mash

[Hefty]

I'm planning to do a CPA this weekend. Kind of a cross between kit and bits and partial mash:
My proposed recipe is:
-1.7Kg CPA tin 18ish IBU in 23L
-1Kg Aussie ale malt
-500Dex
-10-20g POR pellets 20mins (I will calculate this more accurately when I'm not in a rush for approx 25IBU total)
-recultured coopers yeast

Opinions, suggestions? Does this sound ok for OG? I haven't tried calculating gravity from mashed grain before. (Again, I'll try a search when I get back to the computer this afternoon with a bit more time on my hands)

cheers!
Jono.

 

[buttersd70]

Hefty
with the grain, you multiply its potential by your projected efficiency to give the yield. So for most ale malt with a potential approx 80%, and a projected efficiency of 70%, it would give an extract weight of 0.56kg give or take. So with the dex and the tin, it would give 1041 in 23L.

Personally, I would ditch the dex and either up the grain to 1.5kg and add 250g ldm (or dried wheat extract), or just up the grain to 2kg and add nothing else.

I did one that was apa, 1kg JW ale, 250g dry wheat malt extract, for an OG of 1035 in 23L, with POR to complete the bittering, and it turned out pretty good. Not a coopers, but a nice drop. I wasn't trying for a clone. Got down to 1008 (which is where I wanted it) mashed at 68, so if you want it to attenuate further, just mash lower, say 64C.

I think 25IBU in 1041 sounds right.

 

[Hefty]

Cheers Butters!
I'm still juggling amounts of grain because I'm hoping to introduce two brewing mates to partial mashing and I'm not sure if I can fit enough grain in my current setup for 2kg's each. (unless I can convince one or both of them to outlay a little straight up )

 

[Hefty]

Well, the mash went quite well after a small panic when I thought my mashing vessel wasn't big enough.
I ended up doing a double batch so my mate and I could ferment 23L with recultured Coopers yeast and 23L with US-05 and still get a full batch of beer each.

46L final volume, OG 1039
2 x coopers Pale ale tins 3.4kg and 18.5 IBU in final volume
3kg Barret Burston Ale Malt
500g Wheat Malt
8g POR pellets @ 60mins for just over 3IBU
10G POR pellets @ 20mins for just over 3IBU (but really just for the flavour )
total 25IBU

I got 1036 in my pre-boil volume of 21L. If I've calculated correctly, this is 69%. Is efficiency normally calculated on pre-boil or post boil?

Cheers!
Jono.

 

[buttersd70]

I got 1036 in my pre-boil volume of 21L. If I've calculated correctly, this is 69%. Is efficiency normally calculated on pre-boil or post boil?

Cheers!
Jono.

Jono, its either. Pre boil will give you efficiency whats called kettle efficiency, after is brewhouse efficiency. The difference comes down to the loss to trub in the kettle. Loss to evaporation becomes irrelevant, because this is made up by the fact that as water evaporated, the wort concentrates, so one prety much cancels the other out. So the differences should be minimal, and accounting for anything left in the kettle itself should be the difference between the two. It usually only comes down to a couple of percent, tops.