Low Efficiency

[Diggles]

Hi,
3rd BIAB, and resulted in my 2nd low efficiency. 1st and last (today) were low for some reason, had to bump the SG up at the end of the boil with DME and Dextrose. Difference today was I see a drill to grind the grain using my Victoria Grain Mill instead of doing it by hand. Checked to see if the grind wasn't too course or fine. Doing Dr Smurto's Golden Ale, all going fine until I checked the volume and SG at the end of the boil.

Grain bill was:
JW PIlsner 3239g
BM Munich 1080gBM
Wheat Pale 1080g
Wyermann Caramunich 57g

Amarillo as per recipe.

SG before adding extra DME and Dex was 1.020!! Target was 1.047. Mashed at 67 degC for 60 mins, boiled for 90 mins

I'm suspecting it's the mill or I'm not grinding it fine enough. but 80% of the husks are in half, not too much flour tho, has white flecks about 1mm diameter throughout with some flour, but I did think there should be more. I'm hoping you're going to tell me not to worry about betting bad flavours by over grinding. If it is the grinder is it worth double grinding at the same setting or just do it once with a tighter setting.


Diggles

 

[bignath]

Hi,
3rd BIAB, and resulted in my 2nd low efficiency. 1st and last (today) were low for some reason, had to bump the SG up at the end of the boil with DME and Dextrose. Difference today was I see a drill to grind the grain using my Victoria Grain Mill instead of doing it by hand. Checked to see if the grind wasn't too course or fine. Doing Dr Smurto's Golden Ale, all going fine until I checked the volume and SG at the end of the boil.

Grain bill was:
JW PIlsner 3239g
BM Munich 1080gBM
Wheat Pale 1080g
Wyermann Caramunich 57g

Amarillo as per recipe.

SG before adding extra DME and Dex was 1.020!! Target was 1.047. Mashed at 67 degC for 60 mins, boiled for 90 mins

I'm suspecting it's the mill or I'm not grinding it fine enough. but 80% of the husks are in half, not too much flour tho, has white flecks about 1mm diameter throughout with some flour, but I did think there should be more. I'm hoping you're going to tell me not to worry about betting bad flavours by over grinding. If it is the grinder is it worth double grinding at the same setting or just do it once with a tighter setting.


Diggles

What are you measuring your gravity with?

Re double grinding. Ive done it before and from memory may have picked up a couple of extra points but not 20+.
dont bother with it anymore.

 

[kelbygreen]

why not get it ground by a shop with a professional mill to the setting you like?? then you can see if its the mill.

What efficiency are you working it out at??? I got about 62-65% efficiency into fermenter (from beersmith) with BIAB I now get 73-75% with 3v, I tried a few different approaches to BIAB but never got above 68%

 

[GuyQLD]

I've looked at a few biab resources so far but is there any definitive answer to improving efficiency with biab? Bout to do my second this weekend and worried I'm not going to hit the 75ish I got on my first because... I don't know how I did it in the first place

 

[dr K]

Crack size/grind is important but not to 20 points! Your description of your milled grain seems OK (without going onto a spiel about crack ize pro/con).
With BIAB your big concern is temperature, well with any mash its temperature, BIAB is a bit less tolerant, thats another spiel. Check it, buy another thermometer to cross check and check it again.

K

 

[ekul]

How are you actually brewing? How big is your pot? Do you have any pictures? And are you cooling your wort sample before measuring it?

 

[Diggles]

Measuring my gravity with a hydrometer after ice chilling down to 18-20 deg C. Not getting my grain milled at the shop as I'm in Karratha and just carted 50+ kg on the plane to make it more feasible. Pot is a 50Lkeg, first time using it, measuring the volume with a dip stick at just over 1cm per litre intervals.

Strike temp at 67 deg C, mashed in at about 66.5deg C, just dawned on me tat I forgot the mash out......again!! How much efficiency would this cost me?

Diggles

 

[katzke]

Make sure your Thermometer is correct.

Make sure your Hydro is correct.

Write down your steps and check them off.

Follow the BIAB guide. Not sure where the best one is any longer. So many people have posted so many different ways.

Do you stir your mash? How many times and how often?

Do you wrap the keg when mashing so it stays warm?

Have you brewed the same style of beer for your 4 batches?

I do not have any problem getting good conversion or efficiency with BIAB. What is good? Everyone seems to use different numbers. I do not have to make many changes to posted recipes.

Are your volumes correct?

When I first started I had trouble getting the water volume correct. Not sure what program you are using, it should tell you the gravity of your pre-boil wort. If not you can find the formula to figure it out yourself. I have no idea how to do it with litters of kittens. Being in the USA I use gallons and pounds. It took a bit to get the water figured out so I am sure that is why I had early trouble getting predicted results. A bit more or less wort will make the numbers not what you expect. More wort and you can boil longer (remember to not add hops till you have the correct starting volume)

Is the quality of your boil consistent? Again goes to volume.

 

[chunckious]

Measuring my gravity with a hydrometer after ice chilling down to 18-20 deg C. Not getting my grain milled at the shop as I'm in Karratha and just carted 50+ kg on the plane to make it more feasible. Pot is a 50Lkeg, first time using it, measuring the volume with a dip stick at just over 1cm per litre intervals.

Strike temp at 67 deg C, mashed in at about 66.5deg C, just dawned on me tat I forgot the mash out......again!! How much efficiency would this cost me?

Diggles

Het Diggs,

What is your temp dropping to after 60 min mash?
Are you giving a good stir after the grain is in?
I've found that I need to stike in above 70o, good stir the rid the mash of dough balls (they'll kill your eff.). After 60min mash temp has dropped to 65o.

 

[Diggles]

Temp is 66deg C, wrapped in blankets, I got about .5deg C drop over the hour as it's also about 25 deg here at the moment. I stir the mash every 10-15 mins and check the temp.

As for volume, calibrated the keg that morning and double worked out correct when I transferred to the fermentor! Using the "Calculator" from the BIAB site in terms of software. How much would missing out the Mash out step affect?

Diggles

 

[DJR]

Can you post a picture of your crush? Any whole kernels? Was their any doughballs in the spent grain (clumpy bits)? Hydrometer correct?

I don't think missing mashout would cause a massive difference with efficiency, but i don't BIAB so not sure.

 

[mxd]

for a 25 ltr batch, in summer, when I was doing a BIAB, I would need to have the strike temp 3 degrees above fermentation, even if it dropped 3 degrees, that should not cause a 27 point drop, it would just be a bit drier.

For you next batch, try and do a sparge and make sure you drain the bag well.

With the amount of grain you have it appears the recipe is set for 80% efficiency, the best I ever got with BIAB was 67% and was constantly 64%, 50% was my worse and that was doing a 7% beer.

 

[Truman42]

Missing the mash out step shouldn't affect your efficiency at all. I never did it as I couldn't heat my urn with the bag on the element and I always got around 10 points over gravity at EOB. I did do a double dunk sparge each brew though.

How much water are you adding to the mash for that much grain?

If your using the "Calculator" my guess is that as its a spreadsheet you may have inadvertantly changed a figure somewhere which is throwing off your calculations. Did you use the same file for your 2nd BIAB??
Maybe download another virgin copy and put your figures into that and compare them side by side with the one you have..or..Download brewmate and see how that compares.
Ive always found the Calculator, brewmate etc to be very close at its predictions with all else considered.

 

[pimpsqueak]

You could try running brewmate and plugging your recipe in there, set it up for biab and see how much water it recommends vs what your spreadsheet told you.

I'm a big fan of the good ol dunk sparge. I always mash out at 78 deg (holding it for 10mins), then do a dunk sparge or 2 with water I reserved from the initial volume (usually 10 litres)

My last brew was a bigger than normal beer and I was expecting a crappy efficiency, but for the first time I added 1/2 a campden tab and some brewing salts to the strike water ( not randomly. I used the water calc spreadsheet). Got 87% efficiency, my best yet...

 

[bkmad]

My first few biags had low efficiency as well. What improved it for me was adding a mash out step and stirring constantly while raising to mashout. I think the stirring helps to release the malty goodness and the mashout makes it less viscous so less gets caught up in the grain.

I also find I get better efficiency when my recipe has crystal or roasted malts in it as I understand these help reduce ph of the mash. When I do a recipe without crystal or roasted malts these days I add some water treatment salts to help bring the ph down.

 

[Diggles]

My first few biags had low efficiency as well. What improved it for me was adding a mash out step and stirring constantly while raising to mashout. I think the stirring helps to release the malty goodness and the mashout makes it less viscous so less gets caught up in the grain.

I also find I get better efficiency when my recipe has crystal or roasted malts in it as I understand these help reduce ph of the mash. When I do a recipe without crystal or roasted malts these days I add some water treatment salts to help bring the ph down.

Had to use a virgin copy of the Calculator, but will double check with Brewmate. I used all the (about 37L) water recommended, so no sparge, might try a kettle or 2 today as a sparge.
Dowball may be a possibility. Ph of the mash was 5.5, close enough so I didn't bother playing with it.

 

[Diggles]

Had to use a virgin copy of the Calculator, but will double check with Brewmate. I used all the (about 37L) water recommended, so no sparge, might try a kettle or 2 today as a sparge.
Dowball may be a possibility. Ph of the mash was 5.5, close enough so I didn't bother playing with it.

Well thought I'd update on today's brew, mashed in and stired every 5 mins for the hour as opposed to every 15 mins yesterday and hit target, 2 points over at 1.052, good enough for where I'm at at the moment. Can see why everyone get's a storing arrangement now.....needed the exercise tho :lol:

Thanks for the help.

Diggles

 

[kelbygreen]

why stir every 5 mins??? you should dough in and stir and just leave it for 60-90mins or what ever! There is no need to stir you mash threw out the mash. I have not heard of it of used it!

This may not apply at all to BIAB but I add my water to the MT then add about 1/4 the grain stir in and do this 4 times then a good stir at the end. I never suffered dough balls and I am always within 1-4points of my gravity but usually go over.

I dont mean to be rude but why BIAB??? I went threw it all and sure it uses less equipment but I never found it easier or simpler then 3V it may shave 30 mins off your day but I pumped out 64lts in a double and a single batch in 4 hours 45 mins thats with 2 beers with a protein rest, sac rest and a mash out for both and the single was a pils so done a decotion, I will admit it was a full on day and a second set of hands would of helped but I got it all done and dusted in 4hr 45 mins with clean up and thats fly sparging. I also got 74% eff with double and 76% with the single which I calculated at 70%.

Only reason I find BIAB good is to get started or if you cant afford the gear. I struggled to get my rig going and it wont be the last but I never seen BIAB as a system I would always use. After countless efforts to get close to 70% eff and no luck was the last straw, I get clearer beer and better eff with my system and I get 2-3 times the volume lol

 

[bignath]

I dont mean to be rude but why BIAB???

<SNIP>

it may shave 30 mins off your day....

Kelby,

because sometimes 30mins isn't just 30mins if you know what i mean.

Im predominantly a 3V brewer, but starting to get into BIAB as those extra 30mins i could be doing something else. Particularly with my stc temp controlled recirculating single vessel, brewday is damn near stress free. Can't put a quantifiable figure on that.

3V brewing is second nature to me, and very straightforward, but all the cleaning, organising, getting everything ready, strike and sparge prepped, setup, packed away.....i just wanted to experiment with something simpler and less involving.
Have two little brewers running around who need some time, so i'd rather brew less more often than be out of action for most of a saturday 'cause i'm doing back to back brews.

With my single recirculating vessel, i can set my strike water when i get home, forget about it, do the family dinner and put the kids to bed, go back out and mash in at 8:30 and be packed up before midnight. I'd rather do this than spend most of a weekend day brewing, as if i wasn't brewing, i'd be up until after midnight anyway so might aswell knock out a batch.

The beauty about my setup is that to create my single vessel rig, i've basically just modified my HLT from my 3V, so i can go back to 3V at the drop of the hat, if i want to brew my big doubles again, or just knock out a quick as you like keg filler single batch on a weeknight.

But not every one has the space to store two rigs though.

drag out 1 pot and fill with strike water from the hot tap outlet in the laundry. weigh out and crush grain whilst getting to strike temp. takes no more than 10mins.
mash on, quick stir, lid on, reset stc for mash temp. walk away.
after 1 hour, hoist bag and basket arrangement. reset stc for 99 and walk away. takes roughly 15mins to approach boil. sparge if i can be ******.
boil as normal. weigh and add hops. clean small assorted gear during the boil.
wait 20mins for currents to slow down.
transfer to cube 5mins.
clean 1 pot 10mins.
go to bed.

total time: 3hours on the dot.

yes it's only a single batch, but i love brewing, so brewing a big batch or two once or twice a month doesn't appeal to everyone. I'd sometimes rather brew once or twice a week and do different beers.

not getting too much variation in my efficiency with BIAB. It's different but certainly not horrendous. Typically at the moment, the first two or three biab's have yielded 72-75% with minimal effort. Am sure i can get close to 80% by sparging or adding a mashout step.

 

[Diggles]

why stir every 5 mins??? you should dough in and stir and just leave it for 60-90mins or what ever! There is no need to stir you mash threw out the mash. I have not heard of it of used it!

This may not apply at all to BIAB but I add my water to the MT then add about 1/4 the grain stir in and do this 4 times then a good stir at the end. I never suffered dough balls and I am always within 1-4points of my gravity but usually go over.

I dont mean to be rude but why BIAB??? I went threw it all and sure it uses less equipment but I never found it easier or simpler then 3V it may shave 30 mins off your day but I pumped out 64lts in a double and a single batch in 4 hours 45 mins thats with 2 beers with a protein rest, sac rest and a mash out for both and the single was a pils so done a decotion, I will admit it was a full on day and a second set of hands would of helped but I got it all done and dusted in 4hr 45 mins with clean up and thats fly sparging. I also got 74% eff with double and 76% with the single which I calculated at 70%.

Only reason I find BIAB good is to get started or if you cant afford the gear. I struggled to get my rig going and it wont be the last but I never seen BIAB as a system I would always use. After countless efforts to get close to 70% eff and no luck was the last straw, I get clearer beer and better eff with my system and I get 2-3 times the volume lol

Well the reason I stirred was to get the efficiency up, as that's the only thing I can put my low efficiency down to, I looked at all the other options, hence this thread and this looked like the obvious culprit. I may have flaked it, but I hit target SG the second time whilst stirring. The other thing that led me to think of the stirring was that most 3V systems incorporate some mixing mechanism in the mash to increase efficiency, I'm sup prised you haven't heard of this!

BIAB for me was a cheap was of trying all grain without the cost implications, it also allows me to gain experience and a feel for the process in order to design my 3V system when the time comes. Living in whoop whoop with no access to other local all grain brewers makes it harder, so AHB is a huge help and coupled with many books and the internet, means that I'm self learnt. I can't imagine the headaches I'd have designing, building, operating, tweaking a 3V system straight off the bat. I suspect I'd be taking it to the scrap merchant soon after and giving up on home brew altogether as a pipe dream.

After stirring that thing for the best part of an hour, believe me the 3V system is on the cards, or a stirrer in my BIAB vessel at least to tie me over. Got any pics of your system for inspiration?

Diggles