Quick Help Needed, BIAB low efficiency

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zacster

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I did my first BIAB today and the pre-boil gravity was pretty low. It was supposed to be 1.044 and it was more like 1.032. That's going to make for a pretty thin brew. It was supposed to be an American Lager, so it wasn't going to be a big beer in any case.

I ran some of the wort back through the grains in the bag a couple of times and that helped some, but at this point my plan is to boil longer to get the gravity up. I had originally expected a 5.5 gallon batch, but an extra half hour of boil should get me to 5.25 or even lower, and raise the gravity. I'm about 45 minutes into the boil at this point.

Does this sound like a good plan?
 
I had the same issue w/effeciency until I fiqured out what it was with the mill of my grain. It turned out to be about 60%. Since you cover effeciency w/base grain, you can just add some DME/LME to make up the difference (its what I did on my first batch and won a second place medal in the State Homebrew Comp w/it). Using Brewing software down the road, you can just adjust your base grain to get to where you need to be on your OG (or use DME/LME in a pinch)
 
Thanks all. I asked for an extra fine grind, but I didn't think it was all that fine. Also, I didn't do the mash out correctly. Next time I'll watch closer. I'm going to get a basket so I'm less careful with the stirring. I was afraid of pressing on the paint bag.

I do have about 1/4 pound of DME left from my yeast starter. I wanted to keep this all grain though. I guess the yeast isn't all grain!

And I did use BeerSmith2 and it did adjust for the method, but it still expected 72% efficiency. I didn't even get close.
 
yeah; it really is true for my BIAB system. I mill more fine then a normal three tier system... and it makes a difference for me. If I don't Mash out, then I loose anywhere between 3-5 OG points and don't hit my software prediction. A Mash out keeps me perfectly predicted w/my software.
 
One more thing on stirring; With all the water you really don't want to stir it too much.. or the enzymes get stirred up and don't contact the grain enough (low eff?). I always mash for 75 minutes. I dough in an let it sit for 10 minutes; then I stir in a couple times and let is sit 50 minutes not touching it at all. I then do a stir again at 60 minutes and begin my mash out at 75 minutes. I always use a huge blanket "wrapping" the sides and then cover the top. I loose a couple degrees over the hour.
 
My home mill is set to 28 thousands for 72% effeciency; and it has allot of flour. From the Homebrew shop, the fine grind got me to 65%.
 
My LHBS didn't have a mill so I had to get my own. It about broke the bank but I was able to make up for it with the difference in the cost going all grain instead of extract. This is like the mill I got. http://www.amazon.com/dp/B0038NPJVG/?tag=skimlinks_replacement-20

You might have to save up for a bit but it will raise your efficiency and you can brew even when the LHBS is closed if you have the grain on hand. The grains keep well if they aren't crushed, months to possibly years.
 
Last edited by a moderator:
zacster said:
I do have about 1/4 pound of DME left from my yeast starter. I wanted to keep this all grain though. I guess the yeast isn't all grain!
Click to expand...

There's nothing wrong with using DME or some other adjunct to bring the gravity up. Many commercial breweries (big and small) do this on a regular basis.
 
Many die hard all grain brewers will use DME for big beers like Barely Wines just because they too don't have room for all the grain in their mash tuns as well.... don't fear a little DME in all grain when it works for your beer
 
wilserbrewer said:
Interesting...I have wondered if this is myth or fact...thanks
Click to expand...
It's probably a bit of both.
When I started doing a mash out (by adding boiling water to increase the mash temp to 168F, and stirring) my efficiency increased from 75% TO 85%. I fly sparge. I initially thought that it was the increased temperature that caused the increase, but I now think that it was the stirring of the grain bed with extra water before starting the sparge. i.e. It's a fact that my efficiency increased, but a myth that the increase was due to the higher temperature.
One day, I'll verify this by doing a "mash out" with mash temperature water instead of boiling, but that's going to have to wait as life has recently got in the way of my brewing, and I'm nearly out of beer.

-a.
 
So after all that, my final gravity was 1.052. That is HIGHER than the estimate. I don't quite know how that happened. I didn't use the DME either.

It is in the carboy now and I pitched the yeast at 58F, and I want to get it down below 54 before I close up the house. It's a lager if you didn't guess. Unfortunately for my beer, the temps in NYC are supposed to be in the mid 50s this week. I guess it can be put outside, but I keep it in my cold pantry where it is in the high 40s inside the house in a normal winter.
 
Did you check your Wort "hot" ? If so, there is a huge delta in OG related to HOT wort, and for which the Hydrometer is not calibrated too.. IE 108F wort and a sample of 1.042 is actaully 1.050 at the hydrometer calibration temp?

Sometimes First timers check "hot" wort or much warmer wort out of their mash tun for OG thinking it's low, then later when it's all cool they find out it's much higher.

Hot Wort reads much lower OG than it actually is....
 
Maybe that's it. I did take it straight out of the pot after mash out.

Ultimately the quantity was only slightly less than stated, but I left a lot behind in the kettle too, so my batch is under 5 gallons. I have to figure out the siphoning action with the dip tube. It worked fine with water but may have been slightly clogged with wort. At least I left behind a lot of hops and break.

I'm sure it'll be fine.
 
bschoenb said:
One more thing on stirring; With all the water you really don't want to stir it too much.. or the enzymes get stirred up and don't contact the grain enough (low eff?). I always mash for 75 minutes. I dough in an let it sit for 10 minutes; then I stir in a couple times and let is sit 50 minutes not touching it at all. I then do a stir again at 60 minutes and begin my mash out at 75 minutes. I always use a huge blanket "wrapping" the sides and then cover the top. I loose a couple degrees over the hour.
Click to expand...

I can't evaluate your science, but the more I stir, the better my efficiency.
 
zacster said:
Maybe that's it. I did take it straight out of the pot after mash out.

Ultimately the quantity was only slightly less than stated, but I left a lot behind in the kettle too, so my batch is under 5 gallons. I have to figure out the siphoning action with the dip tube. It worked fine with water but may have been slightly clogged with wort. At least I left behind a lot of hops and break.

I'm sure it'll be fine.
Click to expand...

Your beer will probably be great. Sounds like you achieved a higher than expected efficiency in the end and not just because of the additional boil. If you use the same crush and brewing process in the future, you may want to adjust your recipes to account for better efficiency.

You can use brewing software or a chart to correct your hydromoter readings for temperature. You can find a chart at this link:

http://www.howtobrew.com/appendices/appendixA.html

Some people use stainless steel scrubbing pads at the end of their dip tube to filter hops or break and prevent clogs.

Did you have a hose attached to your valve? Did the hose output below the bottom of the kettle? If not, then you will lose your siphon when the wort level reaches the valve, dip tube or not.
 
bschoenb said:
With BIAB; that is not the case; Way too much water/grain ratio
Click to expand...

I did my first two this past weekend and I need to stir every 20 minutes or so or my temp reading might be off. Especially around 45 minutes the temp will have dropped 1-2 degrees. So I stir to make sure it's all accurate and give a little heat when needed.
 
robcj said:
Your beer will probably be great. Sounds like you achieved a higher than expected efficiency in the end and not just because of the additional boil. If you use the same crush and brewing process in the future, you may want to adjust your recipes to account for better efficiency.

You can use brewing software or a chart to correct your hydromoter readings for temperature. You can find a chart at this link:

http://www.howtobrew.com/appendices/appendixA.html

Some people use stainless steel scrubbing pads at the end of their dip tube to filter hops or break and prevent clogs.

Did you have a hose attached to your valve? Did the hose output below the bottom of the kettle? If not, then you will lose your siphon when the wort level reaches the valve, dip tube or not.
Click to expand...

I had a hose attached and it went well below the valve, but it really slowed down. The tubing itself is probably too wide as it is 1/2" ID, but the dip tube is only 3/8". That left a lot of air in it. The other end was in the liquid in the carboy. Maybe I should reduce to 3/8" to maintain better siphon.

In any case, it was happily bubbling away this morning.
 
And now I've plugged my numbers into Beersmith to adjust for temperature and it comes out to 1.050. That gives me 88% efficiency. Neither of these look right to me, but the after boil gravity does bear it out.

As long as it comes out clean and crisp tasting I'll be happy.
 

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