2nd Biab. Really Low Effeciency. Need Help

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hqracer

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I did my second biab today. Recipe was:

Batch Size (L): 23.0
Total Grain (kg): 4.850
Total Hops (g): 83.00
Original Gravity (OG): 1.045 (P): 11.2
Final Gravity (FG): 1.011 (P): 2.8
Alcohol by Volume (ABV): 4.42 %
Colour (SRM): 3.4 (EBC): 6.7
Bitterness (IBU): 16.2 (Average)
Brewhouse Efficiency (%): 70
Boil Time (Minutes): 60

Grain Bill
----------------
4.500 kg Pilsner
0.250 kg Carapils (Dextrine)
0.500 kg Rice

Target OG was 1045 but I only got 1032.

Brewmate calculated 37.5L strike water (incl 4L trub). I have a 59L pot. Very round but not that deep. I have measured the volumes with my steel ruler. 1L is 6.4ml. 37.5L is 24cm etc. The reason I added 4L trub is becuse the pot is so round that to cover the bottom uses quite a bit, but I could probably scale that down to 2L now.

So I cooked the rice in a rice cooker with a lot of water although all the water evaporated, I added some more boiled water to it. Then I brought my strike water (37L) to 50deg. Added all the ingredients for 30m rest then increased temp to 66 and mashed for 60mins. My preboil gravity was 1022 at 66deg. The pot was still 66deg at the end of the mash.

After draining and squeezing the bag I still had 36.4L of wort before the boil. Brewmate calculated 32L at the start of the boil so its like I didnt get the right absorption into the grains. So I only lost around 1L to the grains and I know I measured it right. I crush my own grain with a MM2 set at 0.9ml. Im wondering if that didnt go right?

After the boil I had 29L left. Easily got 25L into fermenter but it was only 1032 at 21deg so I had to add 500g of LME to bring the SG to 1040 which has probably buggered up my whole recipe.

Any ideas?? Im dont know why my efficiency was so low. Around 52%
 
by the sound of it your not getting the boil off you estimated if you got over 25lts for a 23lt batch. I was getting 65% efficiency with BIAB and I tried several things none that worked. I couldn't see me doing anything different to others that claim to get 85%. I switched to 3V and I got 75% and then switched to fly sparging and got 80% I dont want to push any more out of the system so I am happy with what I have achieved.

I am not sure what I was doing wrong with BIAB but I dont think I would go back ATM it only takes me 1 hour more max with my set up (but get 42lts not 21). If you get your volumes right to start with then it will make it easier to work out you efficiency
 
I had the same (similar) issue last brew. Too much water to start with, but was following brewmate. Prob too late now, but boiling longer to reduce volume and boost og helped.
 
HQracer - how vigorous is your boil? I do 21L batches and usually 32L strike (per brewmate). I am regularly using 4.5kg for 21L 1045-1050 beers. Check your grain crush - if that is ***** then ..........
Cheers
BBB
 
Where's the rice in the recipe? How much rice?

You have a target OG in your recipe and no rice, then you say you added rice. Sort that out first - it's difficult to give help when the recipe is wacko.

1.022 preboil gravity at 66C is : 1.041

You lost much more than 1L to the grains.

I fear your issue is with the randomness of your mathematics and your posting. I can count 4 things that don't make sense.
 
In my early BIABs i was getting varying efficiency from just under 50% to 70%. What improved it to usually 75% or over (depending on size of grain bill):
1. Water additions. I'm on cardinia water in melbourne, and small additions have been the biggest factor.
2. I also give it either a stir or move the bag around a little after about 30 minutes.
3. The crush I use is a little finer than for normal brews.
 
Sorry Nick - posted the wrong recipe as I changed it a few days before. I used 500g Rice. 1.6L to the grains? I leave them in another container draining/squeezing and keep addit it back to the boil. What are the other 3 things?

The boil is really vigorous - but rolling. I have a 3 ring burner.
 
Sorry Nick - posted the wrong recipe as I changed it a few days before. I used 500g Rice. 1.6L to the grains? I leave them in another container draining/squeezing and keep addit it back to the boil. What are the other 3 things?

The boil is really vigorous - but rolling. I have a 3 ring burner.

Okay - posting the correct recipe will knock off a few issues immediately.

Did you really have 1.022 at 66C pre boil? Because that's 1.041. "My preboil gravity was 1022 at 66deg"

So where did the sugaz go? Were you diluting it as it was boiling?
 
hmm...good question...you could maybe question that hydro reading then. Im just trying to recall if it was 66deg now - actually I think it may have cooled down when I took the reading because I was scared my hydrometer maynot handle that temp.

The only dilution was extra squeezing from the bag - 500ml-1L max.
 
I really have no idea as I am only just a beginner re. AG. However, hazarding having a guess, I would think that 37.5L water for 23L outcome would be too much water. I would have thought 31L - 33L would be plenty.

It was only last Friday I did a 26L brew and only required 34.6L in my Crown Urn with 3L loss to trub. I understand your pot maybe wider than mine so obviously giving you a bigger evaporation rate but to me, your numbers just don't quite make sense.

e.g. I just put your grain bill into BrewMate and it only calls for 30.94L total water required.
 
my first BIAB i achieved 50%, my second 79%.
Things i did differently:
1) finer crush
2) sparged and squeezed and sparged and squeezed.
3) stir 3 times during 60min mash.
4) added sparge bucket liquids into the boil to keep volume up.
5) did 60 min boil rather than 90 min.

Missed target volume by a few litres, but OG was higher. So correcting for the lost liquid it was 79% if i ended up with target volume in the fermenter / cube.

I have an 80L pot that is 500mm wide. So boil off is mental with it. Will try a double batch while off work over xmas and hopefully i lose less % of water over the boil.
People out there are getting better than 79% efficiency, but they know there gear better than me. I will be happy to consistently get 70%, after all that is what brewmate is basing the receipe requirements on.

Cheers,
D80
 
If your trub loss is set to 4 l like I think you are saying it will be too much. Brewmate will allow you set any amount of trub loss and not vary the expected gravities. Try setting it too 0 or .5 l, any more is extra water that is just diluting your extract maybe?
 
what the f%#k is with your brewmate recipe, it states a grain weight of 4.85kg but your grain bill is 5.25kg??????
if youv put rice into your recipe I assume it will allow for extra water for that, but you seem to have boiled your rice seperately but still used the same amount of strike water.
I agree with earlier post, I put your recipe into brewmate and get 33 litres of strike...is it possible you have used your 'total mash volume' as your strike amount.

I dunno your a long way off your targets.
 
You should try more simple recipes when you're just starting. Stepping up temp and using rice for example is a bit much. Stick with single infusion 100% malt recipes until you have the basics sorted I reckon.
 
When you say you put the rice in another container, do you mean for mashing?

If so the rice should me in with the grain and ideally spread through them so that the enzimes from the grain can get to the starch. If it's just a big ball then it won't be very well converted.

Stirring and squeezing is good for efficiency, especially if you are not doing a sparge (just in a bucket is fine)

A bit of a sparge is good for BIAB efficiency

Doing a mashout (raising the temp of the mash to 73-78* at the end) can help alot with biab efficiency
 
Here is the correct recipe I used.

Recipe Specs
----------------
Batch Size (L): 23.0
Total Grain (kg): 5.250
Total Hops (g): 98.00
Original Gravity (OG): 1.048 (P): 11.9
Final Gravity (FG): 1.012 (P): 3.1
Alcohol by Volume (ABV): 4.72 %
Colour (SRM): 3.2 (EBC): 6.3
Bitterness (IBU): 16.0 (Average)
Brewhouse Efficiency (%): 70
Boil Time (Minutes): 60

Grain Bill
----------------
4.500 kg Pilsner (85.71%)
0.500 kg Flaked Rice (9.52%)
0.250 kg Carapils (Dextrine) (4.76%)

Hop Bill
----------------
7.0 g Nelson Sauvin Pellet (11.5% Alpha) @ 60 Minutes (Boil) (0.3 g/L)
15.0 g Nelson Sauvin Pellet (11.5% Alpha) @ 10 Minutes (Boil) (0.7 g/L)
15.0 g Nelson Sauvin Pellet (12.3% Alpha) @ 0 Minutes (Boil) (0.7 g/L)
15.0 g Wai iti Pellet (3.6% Alpha) @ 0 Minutes (Boil) (0.7 g/L)
23.0 g Nelson Sauvin Pellet (11.5% Alpha) @ 0 Days (Dry Hop) (1 g/L)
23.0 g Wai iti Pellet (3.6% Alpha) @ 0 Days (Dry Hop) (1 g/L)

Misc Bill
----------------
5.0 g Whirlfloc Tablet @ 15 Minutes (Boil)

Fermented at 11C with Saflager W-34/70


Recipe Generated with BrewMate

The rice was mashed in the bag with the malts all at the same time, not a separate container. I also did a mash out to 77deg.

If I reduced my 4L trub loss to 1L in brewmate it comes to 34L strike water. But I stupidly followed the directions and used 37L. Is there anyway to print the brewday instructions in Brewmate so I can post it here?

thanks
 
If your trub loss is set to 4 l like I think you are saying it will be too much. Brewmate will allow you set any amount of trub loss and not vary the expected gravities. Try setting it too 0 or .5 l, any more is extra water that is just diluting your extract maybe?


Cheers - I think this was probably 90% of my problem - effectively watered down the wort. I can now see altering the trub loss value is brewmate is not altering the gravity readings. Grrr.

I also think using rice in my second attempt probably wasnt a good idea - should of just stuck to standard malts and single 60m mash.
 
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