First full volume AG, success?

[DJ_L3ThAL]

Yesterday was my first full volume AG BIAB and it was overall, awesome fun had my sister and her fiancee around and they loved the process to (although they were drinking my stovetop all-grain on tap at the time which always helps...).

Aside from an initial hurdle of a leaking ball valve connection on the keggle wall (fixed with lots of heavy duty blue nylon tape), we were off and running at about 4pm mash in.

I made the mistake of buying those cheap $7 candy thermometers from Fleabay which have 5C graduations, perfect for getting my strike temp right :unsure: , luckily I have an IR thermometer which is very accurate. So the recipe is below:

Dr. Smurto's Golden Ale
American Pale Ale
Recipe Specs
----------------
Batch Size (L): 23.0
Total Grain (kg): 4.888
Total Hops (g): 63.25
Original Gravity (OG): 1.047 (°P): 11.7
Final Gravity (FG): 1.012 (°P): 3.1
Alcohol by Volume (ABV): 4.62 %
Colour (SRM): 6.6 (EBC): 12.9
Bitterness (IBU): 30.0 (Average)
Brewhouse Efficiency (%): 70
Boil Time (Minutes): 60
Grain Bill
----------------
2.760 kg Joe White Traditional Ale (56.47%)
0.920 kg Munich I (18.82%)
0.920 kg Wheat Malt (18.82%)
0.288 kg Caramalt (5.88%)
Hop Bill
----------------
17.3 g Amarillo Pellet (8.6% Alpha) @ 60 Minutes (Boil) (0.8 g/L)
23.0 g Amarillo Pellet (8.6% Alpha) @ 20 Minutes (Boil) (1 g/L)
23.0 g Amarillo Pellet (8.6% Alpha) @ 0 Minutes (Aroma) (1 g/L)
Misc Bill
----------------
0.5 g Irish Moss @ 10 Minutes (Boil)
Single step Infusion at 66°C for 90 Minutes. I decided to mash in 21L and prepare a 10L dunk sparge step which brewmate calculated needing to be 95C

The second issue was that after the 90min mash, the temperature at the grain surface (IR thermom) was saying it dropped to 55C. I just proceeded as I had my dunk sparge pot ready, so stirred that and let it sit for 15min, the keggle had (according to my tap water calibrated refractometer) 1.058 (temp corrected) and the dunk sparge pot ended up with 1.020. Combined and stirred through it was 1.048 (temp corrected).

I proceeded to boil for the 60mins and put all hops in correct although I forgot to add the Irish Moss tablet. I still decided to try and whirlpool, let that slow down almost to the point it was not visibly spinning and then drained through silicon hose into sanitised cube. There was about 1/2 cup of thick hop/break slurry at the bottom (I'm sure some of this ended up in the cube as we had to tilt the keggle to fill the cube as much as possible. I estimate the cube has 23L in it.

Final measurements were hydrometer (temp corrected just before filling the cube) 1.058
refractometer 1.055
hydrometer once sample had cooled to room temp (~22C) 1.055

All in all am happy with how it went, but I have three main concerns:

• Mash temp loss - what impact would this have dropping so low, what does sitting in the beta amalyse segment mean, more unfermentables in the finished wort? To combat this if I am unsuccessful in keeping a solid temp next time, would adding in a mash out step help that?
• Is the dunk sparge step just a waste of time? If I do a full volume mash and manage to do a really good squeeze from the bag would this be achieving (for my newb purposes) a relatively similar result to having the dunk sparge?
• Is the final SG too good to be true? Could I REALLY be getting better than 70% efficiency with the above process? Beginners luck?

Some photos of the day attached also as proof! Haha.

 

[mxd]

well done, nice full cube, to help with temp loss get the sleeping bag/doona/insulation out and wrap it up

 

[DJ_L3ThAL]

well done, nice full cube, to help with temp loss get the sleeping bag/doona/insulation out and wrap it up

I had about 6 towels draped over the top which was what I used for the stovetop method. I have some rubber I can use to insulate it next time so will try that plus sleeping bag/towels.

Am hoping someone has suggestions on why the numbers were still so good with obvious known flaws in the method?

 

[Dan Pratt]

Hi,

Congrats on your first on many AG brews!

:lol:

 

[technobabble66]

Looks great, DJ !

I'm still a bit newbie, so i'll let the more experienced brewers answer your questions properly.
But FWIW, i prefer to do a sparge (dunk or rinse) & seem to get remarkably high extraction rates (considering generally how amateur & new my setup is). I BIAB in an urn & the last 3 batches seem to get around 85% efficiency. So i've had to dilute my 3 brews from 21-23L to 27L - which should screw with my bittering, but i think these have ended-up initially over-bittered (or i'm a wuss when it comes to handling bitterness in beer) and the dilution brought it back to balance. So it's kinda worked out for me, in spite of these adjustments on the fly.
I like the sparge thing, because i'm a tight arse & can't stand the idea of wasting all those yummy sugarz still sitting in the grain bag. Though supposedly the loss can be accounted for by just chucking in an extra 1/2kg of grain (~$3 at most).

Brewing - not just a balance of hops & malts, but a balance of science & art B)

Congrats on the brew day success!

 

[Dan Pratt]

4.9kg of malt to 23L @ 1055 would be about 85% efficiency....your brewing benchmark!

 

[DJ_L3ThAL]

thanks for the replies guys! anyone else got ideas on specifically the last three dot points of the OP?

 

[DJ_L3ThAL]

anyone else got ideas on specifically the last three dot points of the OP?

Noone?!

 

[philmud]

A) the drop in temp would be likely to result in a MORE fermentable wort, because it would encourage more beta-analayse - this converts starch to more fermentable sugars. Holding the temp more steady will result in a beer with more body. I'm not sure a mash-out stage will affect this, but it will theoretically increase your efficiency.
B ) I rinse my bag after squeezing (insert smut) with a couple of litres of mash-out temp water. I figure that it will necessarily increase the sugar in my wort so increase my efficiency (I leave this water out of my mash, so volume isn't increased). I've read brewers say that they don't think sparging is necessary for BIAB - you could try skipping it and see if it makes a difference to your process.
C) its very high. I've done 80% efficiency BIAB once, but am usually between 65 - 70. Do a few more brews an see where yours sits. Last brew I did, the pre-boil SG suggested about 85% but the post boil SG was actually lower! I used a calculator to convert the SG for the temperature, but something must've gone wrong because it's impossible for the boil to decrease SG!

Edit: I'm on a ******* iPhone and I ******* submit my post too early!

Edit MKII - link to Palmer on starch conversion. http://www.howtobrew.com/section3/chapter14-5.html

 

[DJ_L3ThAL]

Just to report back on this, not batch/dunk sparging has significantly reduced my efficiency, averaging about 65% without it (although as you've implied this may just be where it will sit normally and I got lucky on the first shot or measured incorrectly?). Have still only dunk sparged the one (first) time, so will try that on the next go and see if it lifts again.


Second (new) issue:
Also am in cahoots with myself over my keggle tap location, it seems quite high and I measured 6L of liquid below it when it is flat, where perhaps 3-4L of this is actually trub after whirlpooling. But because I need to tilt my keggle to fill the cube as much as possible it disturbs this and I'm getting some trub and hot break etc into the cube. I'd prefer to be able to just fill the cube with the keggle flat, then I'll take the bulk of the remaining trub/break into PET bottles for starters.
Is addressing this just a matter of increasing my strike water volume. For some reason Brewmate does not seem to make any adjustments to the recipe ingredients, OG or efficiency when I adjust the "losses to trub" option, that just doesn't seem correct to me?

4kg grain in 32L of water is surely not going to get the same result as 4kg of grain in 36L of water??? Why does Brewmate not calculate this correctly?