First AG - BIAB - 10 gal oatmeal stout - Feedback please

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Richardwhittaker

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Location
Amherstview, Ontario, Canada
Primus Oatmeal Stout

10 gal

15.5 lb 2 row
4 lb Flaked brewers oats
1.5 lb Chocolate malt
1. lb Caraamber
.5 lb Crystal 120L
.5 lb Crystal 40L
.5 lb Roasted barley

4 oz Kent Goldings @ 60 min

Safale S-04

estimated eff 70%
Target OG 1.055
Target FG 1.014
Target ABV 5.4%
IBL 25.5
SRM 39.9

60 min mash @ 155 F (10 gal)
10 min mash out @ 170

Equip.
Electric keggle
Mesh bag (double layer sheer curtain material)

Prep work:
Clean equip
Measure and crush grain (fine crush as BIAB = No stuck sparge)
Clean and prep brew area

Brew day Process:

Heat 12 gal to 160
Put bag in keggle
Stir in grain
Adjust temp if needed
when @ 155 F cover and hold for 60 min
(adjust temp if needed)
Raise temp to 170 F hold for 10 min
Lift and drain bag (pulley attached to ceiling)
Dunk bag and drain again
When bag is done draining give gently twist and set aside
turn on heat and top up kettle to 10 gal
When boiling add hops(in hop sock) and boil for 60 min
While boiling sanitize equipment, dump grain, rinse bag, tidy up and set up immersion chiller
@ 50 min place wort chiller in boiling wort
@ 60 min turn off heat, run wort chiller (drain hot water into bucket for cleaning water) and top up to 10 gal
When temp reaches 60 F drain into 2 sanitized buckets
Take OG
Add 1 packet of S-04 (11 grams) to each
Have a home brew while I clean up
3 weeks in primary then keg
2 weeks in cooler carbing
Enjoy

So what did i miss? Should I change anything? Any comments? Suggestions? As I have never done this before I am open to any feedback bad or good.

What I see as possible stumbling point are
1. Total volume of grain + water exceeding my 15 gal keggle capacity
2. Potentially scorching the mash/bag during mash out
3. Having trouble pulling bag out past lip of keggle
4. Over shooting or under shooting target efficiency
 
Well I can lay one worry to rest. I filled my keggle to see how long it would take to get to temp ant to see how accurate my thermometers are (one cheap digital meet thermometer one cheap bi-metal meat thermometer and on floating thermometer. I figured with three I could get a good feel for if one was off. (two agreed and one was almost exactly 10 F off. When I was heating the water I took a strip of the material that I made my bag out of and hooked it around the element. Nothing happened to it so I think I should be safe on that front.

Richard
 
"Lift and drain bag (pulley attached to ceiling)
Dunk bag and drain again"

why? I do BIAB, and I've thought of this, but I don't see the "science" behind doing it, it just feels like the right thing to do. I mean, you are just dunking it back into sugar water, so i don't imagine it would extract any more sugar from the grain?

also, 4 lbs of flaked oats? Thats a lot, but I'm not an expert in the stout area.


One more piece of advice - I get amazing efficiency with BIAB if I take a tea kettle of 180 or so water and slowly pour over the top of the bag as it is hanging and draining. I use anywhere from 1-2 gallons for this (5 gallon batches). It acts as a kind of "sparge." its not hard to do, and i think its definitely worth the effort.
 
It seems like way too much crystal too me, with 3.5 pounds. I used 8 ounces of crystal in my oatmeal stout (5 gallon batch, though). I'd use 3 pounds of oatmeal for a 10 gallon batch, at most, but I know others have used 4.

What did you use for your efficiency % ? Without a sparge, I'd expect a fairly low efficiency number, especially if you're topping up to 10 gallons. You'll probably need about 11.5 gallon to start with, though, and boil down to 10 gallons over the course of the boil.

If you have to top up with about 3 gallons to get to 10 gallons, you'd really reduce your efficiency.
 
The dunking is something I picked up while reading up on BIAB on the Australian sites. From what I gather the wet grain still has a higher concentration of sugars then the wort after it has been drained the first time. The dunk dilutes that and allows for a few more points of efficiency. There will come a point when it will no longer make a difference as the gain and the wort reach an equilibrium. Also you have the wort washing over the grains three times once in the original drain, once in the dunk and once in the secondary drain. I decided to try this rather than doing the sparge the bag method as one of my goals is to keep the process as simple as possible. If I find I have poor efficiency I will try the sparge the bag method.

The oats are higher than most homebrew oatmeal stouts. I am looking for a big mouth feel . From what I read some of the original oatmeal stouts were brewed with 30% of the grain bill as oats. One of the reasons for using less oats is to avoid stuck mashes, this is not an issue with BIAB.

Thank you for your feedback anything that makes me think about why I'm doing what I am planning on doing is welcome
 
It seems like way too much crystal too me, with 3.5 pounds. I used 8 ounces of crystal in my oatmeal stout (5 gallon batch, though). I'd use 3 pounds of oatmeal for a 10 gallon batch, at most, but I know others have used 4.

What did you use for your efficiency % ? Without a sparge, I'd expect a fairly low efficiency number, especially if you're topping up to 10 gallons. You'll probably need about 11.5 gallon to start with, though, and boil down to 10 gallons over the course of the boil.

If you have to top up with about 3 gallons to get to 10 gallons, you'd really reduce your efficiency.

I used the default 70% efficiency in BrewTarget. From what I have read on BIAB a lot of the guys are getting decent efficiency. Part of this is due to the thin mash and the fact that you can use a finer crush without worrying about a stuck sparge. The grain bill is slightly modified from an oatmeal stout that I found on this site.
Recipe Type: All Grain
Yeast: S-04
Yeast Starter: no
Batch Size (Gallons): 5.25
Original Gravity: 1.055
Final Gravity: 1.018
IBU: 36
Boiling Time (Minutes): 60
Color: 35
Primary Fermentation (# of Days & Temp): 14days @ 65F
Secondary Fermentation (# of Days & Temp): no

OG 1.055 (80% efficiency, adjust base malt for your system)
IBUs 36
6.75# Pale malt
0.5# roasted Barley (350l)
0.75# chocolate (330l)
0.5# crystal 40
0.5# crsytal 120
0.75# victory
1# flaked oats
2oz Willamette hops at 60
S-04 yeast

It looked good, I like a sweeter stout with a big mouth feel. The place where I got the grains from did not have the victory so they suggested using the Caraamber as a substitute. The rest is a simple doubling except for the oats and an addition 1/2 lb of 2 row. What would you suggest I reduce and by how much?

Richard
 
If you wanted a sweeter stout, I would lay off the roasted barley a bit. You already have 1.5 lbs of chocolate malt, which as you know still imparts a bitter roasted character (despite its chocolatey sweet name). For mouth feel, a dosage of malto-dextrin might be warranted.

you also might consider adding lactose for sweetness.
 
Is your bag strong enough to hold that much wet grain? That's what I'd be worried about.

The grain bill is 23 LB or roughly 10 kg calculating @ .5 - .75 liter/kg that is 5-7.5 liters of water absorption that is another 10 - 15 lb of weight. so a total max of 45 lb. With wet grain there will be an even distribution of pressure so no point loads. I tested the bag with 2 15 lb dumbbells the dumbbells have a greater point load so the pressure on the fabric would be greater than the pressure caused by the grain so the fabric should hold. The bag was sewn with no seams so I don't have to worry about have to worry about a seam letting go.

The bag was sewn with two layers of fabric so I think I'm safe....(fingers crossed)


Richard
 
If you wanted a sweeter stout, I would lay off the roasted barley a bit. You already have 1.5 lbs of chocolate malt, which as you know still imparts a bitter roasted character (despite its chocolatey sweet name). For mouth feel, a dosage of malto-dextrin might be warranted.

you also might consider adding lactose for sweetness.

How much would you suggest?
 
I'm not sure which ingredient you're referring to when you say "how much," but I'll give all three:

for cutting down the roasted barley - .5 to .75 lbs should suffice if you combing with that much choc malt.

For Malto-dextrin- I've used 8 oz in a 5 gallon batch with success

For lactose - i've never made a sweet stout - but most 5 gallon batches I've seen have a full pound of lactose in them.
 
If you have to top up with about 3 gallons to get to 10 gallons, you'd really reduce your efficiency.

Maybe I'm not understanding how efficiency is calculated... but I don't see how topping up will reduce efficiency. I thought efficiency was measured against the theoretical amount of sugars that is in the grain. IE if I get 60% of the sugars out of a given amount of grain then I have 60% efficiency. Adding water to your wort after you are done extracting/converting the sugars will not effect the percentage of the potential that you extracted. It may make measuring your efficiency more difficult (you would have to recalculate the gravity of a perfect extraction/conversion for your new volume).

Or am I totally out in left field about this?(I have not read up on how to calculate efficiency so I may be missing a factor which will throw off my idea of how it would be done)

Richard
 
No, you're right about the efficency. Except you will probably get about 6 gallons out of your mash. If you're not sparging, you will be adding LOTS of water to dilute your wort. So, you will NOT end up with a brewhouse efficiency of 70% in the final wort, even if you do manage to get good conversion and extraction efficiency.

You're going to end up with a very low OG, unless you use more water in the mash, or sparge. If you're using a total of 10 gallons of water, don't forget that the grains will absorb about .1 gallon per pound. So, you'll have very little wort coming out of the batch. "Sparging" by dunking the grains back into the wort is a very inefficient way to get more sugars into solution. You'd be better off to have 4 gallons of 175 degree water in a different container, and dunk your grains in there to get more sugars out, and then combine the wort. That may give you an OG closer to the target.

You've got about 3-4 times the amount of crystal I'd use. If you like it sweet, that's fine but it's going to be cloyingly undrinkably sweet. If you want to make a sweet stout, most have about about 7-10% crystal, and then add some lactose for sweetness. I wouldn't use more than 10% crystal regardless.
 
I have cut the amount of crystal to 10% of the grain bill. I don't have lactose and don't know where I would get some so I will leave that as a note to try another time. As for the efficiency I can see where you are coming from I have 23 lb of grain @ .1 gal/lb that would be 2.3 gallons of water. According to this http://www.thebrewingnetwork.com/forum/viewtopic.php?t=4650&postdays=0&postorder=asc&start=0/fa You will lose significantly less wort to grain absorption with BIAB. Using .75 liter/kg he gives as the max amount that would be approx 2 gal lost. using the lower number of .5 liter/kg that would end up with 1.3 gallons lost.

With traditional mashing, you have a more concentrated wort after the mash. This would mean that the wort absorbed in the grain has a higher percentage of the total sugars. If you were to skip the sparge in the traditional method, and topped up to reach your volume then your brew house efficiency would take a huge hit.
With BIAB you mash in the full amount of water so you have a less concentrated wort so you would lose less efficiency by not spargeing, as the wort absorbed by the grain is more dilute. Following this logic I should be mashing with about 11.5 - 12 gallons of water .

Thank you for forcing me to think through it!

Anyone know how much volume 23 lb of grain will take up?
 
Just started my mash! I am sitting at the max capacity of my keggle. (this means my 23 lb of grain takes up 3 gal in the mash) I under shot the temp by five degrees but it was simple enough to turn the heat on and raise the temp.

Richard
 
With no sparge and topping up the boil just under 1 gal I ended up with an OG of 1.054 which is right on the money according to Brewtarget. I ended with 10 gal finished wort this gives me a Brewhouse efficiency of 70%.

I'm happy with that for a first go.
 
For my first batch I didn't. I have an low density immersion element and I did short test to see if it would melt/scorch the bag. The test showed no effect on the bag material so I felt I was safe. Unfortunately it seems the tip of the element gets hotter than the rest and I had a small hole melted in the bag. I have sicnce retrofitted my setup with a piece of 1 1/4 inch perforated copper pipe which the element sits inside. This keeps the bag off the element and I had no problems with my next batch.
 
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