Biab#3 - Help Pls, Too Efficient?

[Diesel80]

Hi All,

brewed up my 3rd AG last night, had a ball doing it apart from not finishing up till 1:00am.

Anyway I had a target SG of 1.047 @ 27L @ ~26 IBU in brewmate.

I ended up with a completely full willow 25L cube no-chilling overnight so got about 26-27L as per target.

I let the trub settle overnight and seperate so i could measure the SG of the wort.
1.060 i got. Way above what i was targeting.

Receipe Below:
5Kg M/O
300g Heritage Crystal
50g Cara 2 Special

Hops
27g Fuggles(5.5AA) @ 60
40g Styrian(3.5AA) @ 15
total ~ 26 IBU.

1/2 Whirfloc tab

Mashing Notes:
Mashed in about 37L water for 60 mins @ 66-67 on the analogue thermo, and 64 on the STC-1000 (not calibrated). Very min temp drop over the hour.
Extracted bag, squeezed etc, topped up to 39L which was receipe target pre-boil vol.

Measured Gravity, was 1.041-1.042, target preboil was 1.039.

Boiling: 60mins.

Whirlpooled and siphoned into cube.

Questions:
1) So i don't want 7% beer, so considering diluting it to near target (only have a 30L fermenter ) How can i increase the IBUs in the diluted wort back to ~25 IBUs?

Can I approximate the IBU dilution using the same ratio as the SG dilution?
I think i will end up with about 33L of total wort after dilution. Will need to borrow a fermenter or go and buy a smaller one for fermenting the dregs.

Any advice from those who have found themselves in this position? It would be welcomed!

Cheers,
D80

 

[donburke]

Hi All,

brewed up my 3rd AG last night, had a ball doing it apart from not finishing up till 1:00am.

Anyway I had a target SG of 1.047 @ 27L @ ~26 IBU in brewmate.

I ended up with a completely full willow 25L cube no-chilling overnight so got about 26-27L as per target.

I let the trub settle overnight and seperate so i could measure the SG of the wort.
1.060 i got. Way above what i was targeting.

Receipe Below:
5Kg M/O
300g Heritage Crystal
50g Cara 2 Special

Hops
27g Fuggles(5.5AA) @ 60
40g Styrian(3.5AA) @ 15
total ~ 26 IBU.

1/2 Whirfloc tab

Mashing Notes:
Mashed in about 37L water for 60 mins @ 66-67 on the analogue thermo, and 64 on the STC-1000 (not calibrated). Very min temp drop over the hour.
Extracted bag, squeezed etc, topped up to 39L which was receipe target pre-boil vol.

Measured Gravity, was 1.041-1.042, target preboil was 1.039.

Boiling: 60mins.

Whirlpooled and siphoned into cube.

Questions:
1) So i don't want 7% beer, so considering diluting it to near target (only have a 30L fermenter ) How can i increase the IBUs in the diluted wort back to ~25 IBUs?

Can I approximate the IBU dilution using the same ratio as the SG dilution?
I think i will end up with about 33L of total wort after dilution. Will need to borrow a fermenter or go and buy a smaller one for fermenting the dregs.

Any advice from those who have found themselves in this position? It would be welcomed!

Cheers,
D80

that grain into 27 litres ends up being 96% efficiency at 1.060

something aint right,

who weighed the grains ?

hydrometer might be out, might have picked up some dense trub in the reading ?

 

[Diesel80]

I weighed the grains much more carefully this time than last, and reduce them down by about 600g over last batch because my beer was too strong then.

The wort i measured was the clear layer out of the 4L of trub that i put in a container to settle out the heavy stuff overnight.
Was clear in the hydro tube.

I am hoping you are right that that it is wacky. 96% is not what i want when planning on 74%!

The hydro reads 0 in water and has returned expected values at fermentation end of previous brews. May borrow another to test what is in the cube itself.

Could their be something in with the trub mix that is causing wacky gravity readings? Is it not good using settled trub to get SG readings?

 

[Spork]

What temp was the wort you tested? Could be affecting hydrometer reading.

Am I correct in assuming that 50g of plain sugar disolved in 1 litre of water (or 5g in 100mL) should read 1.050? Might be worth testing hydrometer accuracy at around the gravity of wort as well as just 0.000

 

[argon]

If it truly ends up being a 1060 wort. Then do a small reboil of the cubed wort with some extra hops to up the IBU (with added late hoppiness :icon_drool2: ) Then dilute to a more modest OG... say 1050-1055. That'll still be good and you won't need to add too much extra water.

Follow the guide here - Late Hopping And No Chilling Guide

 

[Diesel80]

Good idea spork, will test the hydro tonight to verify.

Argon, will check that link, thanks mate.

Cheers,
D80

 

[tiprya]

Your reading looks about right - 39L at 1042 should be ~1060 boiled down to 26L

I think you are just boiling too much liquid off.

Perhaps you should mash with less grain and water? - what sort of pre-boil volumes do other people start with?

 

[Diesel80]

Your reading looks about right - 39L at 1042 should be ~1060 boiled down to 26L

I think you are just boiling too much liquid off.

Perhaps you should mash with less grain and water? - what sort of pre-boil volumes do other people start with?

Perhaps i am tip,
I have a 500mm wide 80L pot so my boil off is nuts.
I have consistently been getting only 20-23L out of the kettle into the cube.

Starting with a 37L strike water, my receipe called for 42L. But i topped up 3L after mashing to hit 39L preboil after squeezing etc.

I ended up with about 30L trub/wort combined and had 4L trub left in kettle at end of siphon, this time round i measured so i know for next time.

Looks like a mini hop boil will be on the cards as well as a dilution.

Cheers,
D80

 

[keifer33]

Just to clarify something you fill the cube to 25l then the day after you transfer to another container losing around 4l to cold break and any boil tub which is what you used for a reading? I'm going to be honest and throw a wild theory out there which an 'expert' might be able to clarify. Could the sugars not be evenly distributed the entire 25l and being concentrated to the bottom during the natural cooling of the cube? Thus by pouring off the top 21l and not taking a reading of this but taking a reading of the concentrated wort is inaccurate.

 

[tiprya]

Starting with a 37L strike water, my receipe called for 42L. But i topped up 3L after mashing to hit 39L preboil after squeezing etc.

You should have lost ~5L (1L/kg) of water absorbed by the grain.

You should be able to adjust your brewing software to account for the large boil-off in your system.

Efficiency in the 90's is unlikely, although not impossible, so there may yet me a measurement error somewhere.

 

[argon]

So with your target of 27L of 1047 @ 26IBU you now have 27L of 1060 @ 23.9IBU

If you were to dilute back to 1047 you would have 34L @ 20.3IBU.

So do the small 10min reboil with 55g of Styrian and you should have your 26IBU once topped to 34L

 

[Diesel80]

Just to clarify something you fill the cube to 25l then the day after you transfer to another container losing around 4l to cold break and any boil tub which is what you used for a reading? I'm going to be honest and throw a wild theory out there which an 'expert' might be able to clarify. Could the sugars not be evenly distributed the entire 25l and being concentrated to the bottom during the natural cooling of the cube? Thus by pouring off the top 21l and not taking a reading of this but taking a reading of the concentrated wort is inaccurate.

Hi Keifer,

I filled the cube full and it is sealed atm. The trub was what was left over in the boil kettle.
I tipped this into a 5L measuring just and left it overnight to settle the hop / break matter to the bottom, and then allow the cleared wort to be easily scooped into the hydro tube.

So to confirm i still have a full 25L cube (to the brim so likely 26-27L) of unknown gravity.
I am making an assumption that the stuff i tested should be the same!

Could be a bad assumption.
Cheers,
D80

 

[keifer33]

Ah scrap my idea then misread the info.

 

[Diesel80]

Efficiency in the 90's is unlikely, although not impossible, so there may yet me a measurement error somewhere.

I support the theory that i may have some errors in a measurement somewhere.

I have the following areas that could be the cause:
1) Having measured more grain than i thought.
2) Having measured less water than i thought - will verify the markings on my mixing spoon.
Sure they were 27L and 35 respectively.

I do know that the final vol i have is between 25-27L
I have the gravity of the kettle trub dreg wort @ 1.060 taking at room temp.

I don't have the gravity of what is in the cube, and will only know this once i have cracked the cube and ready to ferment. - i have made an assumption that the kettle dregs would have the same gravity as the cube contents.

The likeliest candidates are:
too much grain
strange happenings with kettle dregs.
hydro readings being out.

Cheers,
D80

 

[malt_shovel]

I know there are tit-bits here and there throughout your replies, but it would help to have from the outset, the process in it's entirety. This makes it less ambiguous for the readers. Not having a go, just trying to help with people who provide only minimal info on a problem which could have multiple factors.

The other point you may want to consider is that with higher wort gravity during the boil, will translate into lower hop utilisation. Not sure when you are adding your hops, so it may be a moot point (again need more complete info), so maybe need to be a bit more generous with additional hopping during your mini-BIAB after dilution.

I see this is your 3rd BIAB, but not sure if you have settled on what IBU calculation you prefer (Tinseth / Rager etc). I find in BrewMate that the average setting gives a lower IBU than I expect for my system/tastes, so I use Tinseth. For your own info I would play with this setting in BM with your specific recipe to see how the IBU's change with whatever calculation method. This will give you a range of additional IBU to go seeking in the BIAB to cover not only the dilution, but also what range is present in the calculation...for me, it's these things which makes brewing more craft than science and keeps me interested.

Cheers
:icon_chickcheers:

 

[Diesel80]

I see this is your 3rd BIAB, but not sure if you have settled on what IBU calculation you prefer (Tinseth / Rager etc). I find in BrewMate that the average setting gives a lower IBU than I expect for my system/tastes, so I use Tinseth. For your own info I would play with this setting in BM with your specific recipe to see how the IBU's change with whatever calculation method. This will give you a range of additional IBU to go seeking in the BIAB to cover not only the dilution, but also what range is present in the calculation...for me, it's these things which makes brewing more craft than science and keeps me interested.

Cheers
:icon_chickcheers:

I am using whatever the standard is in Brewmate with nochill box ticked.
have found brews to be quite bitter to date with only taget 30-35Ibus. They do mellow over time.

Not sure i measured accurate hop quantities first 2 brews as i was just learning the process, near enough was good enough to get a couple of notches in the belt.

Now, this brew was the first i have tried to keep track of extra information for reference.
Also trying to address the bitterness, with additional crystal over prior receipes and knocking back the hops slightly.

I will be brewing again in a couple of days and will forensically record everything i do that time round for #4. Hopefully by this stage i will have refined certain steps.
Going to get a steel rule and calculate L/per CM for my pot. That will take the guess work out of #4 as far as measuring preboil vol, mash vol, boil off etc.

Cheers,
D80

 

[PistolPatch]

Diesel, there's so much to write, I don't really know where to start.

Maybe have a read of this post first.

From that post you'll see that there are many hurdles to jump on measurement and software. For example, you'll continually see posts on forums that just use the word, "efficiency," (just like software does). There are many different types of efficiency and most software does not make this clear.

Furthermore, most forum posts (due to existing software) treat whatever efficiency they use as a constant whereas it is really a variable*. The most useful or pure efficiency figure to talk about from one brewer to another is, "Efficiency into Kettle" (EIK). This is pretty much the same as or also known as "mash efficiency" or post-boil efficiency."

On a low gravity brew, you have less grain and it is getting 'washed' by a lot of water so your EIK (and therefore all other efficiencies) will be high. A high gravity brew has more grain getting 'washed' and will obviously result in a lower EIK. No software addresses this even though the difference between a high gravity brew's EIK and a low gravity brew's EIK will be around 25%.

Let's forget software etc for a moment. The most important thing for a new brewer to realise is that measurements on a single brew are never trustworthy - see here. The more measurements you take when you are starting out, the faster you will realise what level of respect to give measurements. This might seem like contradictory advice but it's not.

There's a team of people at BIABrewer.info that have been working very hard for over half a year on developing "intelligent" brewing software that will make all the 'tricky' things very easy for both beginners and advanced brewers (including traditional brewers). Most of the thinking/essential work has been done so we should see some sort of release there quite soon.

It's a bit of a process becoming a member of BIABrewer.info with the rights to post and download there at the moment but this will change. Until then, anyone who BIAB's and wants correct/detailed answers to their questions will be well-served by going through that process. The figures and advice you'll get there are definitely the best available.

Hopefully anyone that joins there can then pass that quality information back to other AHB members.

:icon_cheers:
PP

* Stux from this forum has done some great work on this variable efficiency aspect.

 

[black_labb]

I've collected what's in the bottom of the kettle for an sg reading and it is always quite a bit higher than the wort in the cube even after letting it settle in the fridge overnight. I don't really understand why exactly but I've stopped doing it as it doesn't help

 

[Diesel80]

Pistol, thanks for taking the time to post. I have browsed that site a few times, but perhaps it is time to get stuck into it and become a member.
I will be BIAB'ing for a while yet so it will be worth my while.

Black_labb, interesting you have experienced the same. Have been to sh!tscared to touch the cube in the fridge because i am not sure what i want to do with it if it is higher gravity than i want. Don't want to crack the seal and let nasties in. Will probably do as argon suggests above.
If what you say is true, then i may have 1.048 beer in the cube and not even know it!

I will know tomorrow either way as i need to get it fermenting.

Cheers,
D80

 

[katzke]

I would not worry about fixing mistakes as a new brewer or even one with experience. Just finish it, see what it turns out like and take notes.

Way too many brews and too little time to worry over one.