BIAB Mashing Out

[wsmith1625]

I grind pretty damn fine and I'm nowhere near 100% converted at 152F in 60mins. There is a typical stall for me between 40 and 60mins so at 40, I slowly ramp over about 10mins to 160, hold for 5, ramp to 170 over 10. That gets me an average of 10% more conversion in the same 60 minutes. This is with Simpsons GP, Muntons Maris, Briess 2row FWIW.

Thanks Bobby. I think I'll give that a try and see how it goes. I may also buy some iodine tincture and start testing my mash before boiling.

 

[Apple_Jacker]

Reviving this thread.

Yesterday I used my new 16 gallon kettle, so I can finally do full volume mash. After my 60 minute mash, I heated the wort up to 170 while stirring my grains, then pulled the grain bag out and let it drip into the wort while bringing it up to boil. My pre-boil gravity was a higher than expected 1.042 anticipated gravity, 1.055 measured gravity). My efficiency was probably higher due to milling the grains almost to flour.

I didn't squeeze the bag this time just to see the difference. There was definitely still wort in there after the 60 minute boil. I squeezed it a little just to see what was left in there before composting it. If I had to guess, there was 1/4 gallon or more stull stuck in there.

 

[doug293cz]

Reviving this thread.

Yesterday I used my new 16 gallon kettle, so I can finally do full volume mash. After my 60 minute mash, I heated the wort up to 170 while stirring my grains, then pulled the grain bag out and let it drip into the wort while bringing it up to boil. My pre-boil gravity was a higher than expected 1.042 anticipated gravity, 1.055 measured gravity). My efficiency was probably higher due to milling the grains almost to flour.

I didn't squeeze the bag this time just to see the difference. There was definitely still wort in there after the 60 minute boil. I squeezed it a little just to see what was left in there before composting it. If I had to guess, there was 1/4 or more stull stuck in there.

1/4 what (cup, qt, gal, liter) still stuck in there?

Brew on

 

[Apple_Jacker]

1/4 what (cup, qt, gal, liter) still stuck in there?

Brew on

1/4 gallon

 

[AZ Maverick]

I'm new to all-grain brewing and chose to go BIAB.
I just made my second batch a few days ago.
I have a Hullwrecker 2 roller mill set to .028" and did a single pass on my grain bill.
I mashed for 90 minutes at 152° F and at the end of the mash I just lifted the bag and squeezed it pretty well, I did not 'mash out' or sparge.
My measured conversion efficiency came out to 82%.
I'm not sure if I should do anything else to increase that efficiency or just call it good-to-go.

 

[doug293cz]

...
My measured conversion efficiency came out to 82%.
I'm not sure if I should do anything else to increase that efficiency or just call it good-to-go.

Are you sure you are talking about conversion efficiency, and not mash efficiency? Mash efficiency is the product of conversion efficiency and lauter efficiency. 82% is terrible for conversion efficiency, but is good for mash efficiency. How did you measure the efficiency you reported?

Brew on

 

[AZ Maverick]

Are you sure you are talking about conversion efficiency, and not mash efficiency? Mash efficiency is the product of conversion efficiency and lauter efficiency. 82% is terrible for conversion efficiency, but is good for mash efficiency. How did you measure the efficiency you reported?

Brew on

I'm new to this all-grain world, so excuse my newbieness....
I used the Brewer's Friend 'Brewhouse Efficiency Calculator', specifically the efficiency for 'Conversion' and/or 'Pre-Boil' as they were the same for me.
I rechecked and I did make a mistake which lowered my conversion efficiency down to 79.7% (I accidentally included grain absorption water).
Using the same calculator, my 'Brewhouse Efficiency' ended up at 77.58%.

I saw this on BYO.com for extraction efficiency and figured "OK, no big deal - I'm in the ballpark" - is this info not correct?

 

[doug293cz]

I'm new to this all-grain world, so excuse my newbieness....
I used the Brewer's Friend 'Brewhouse Efficiency Calculator', specifically the efficiency for 'Conversion' and/or 'Pre-Boil' as they were the same for me.
I rechecked and I did make a mistake which lowered my conversion efficiency down to 79.7% (I accidentally included grain absorption water).
Using the same calculator, my 'Brewhouse Efficiency' ended up at 77.58%.

I saw this on BYO.com for extraction efficiency and figured "OK, no big deal - I'm in the ballpark" - is this info not correct?
View attachment 722127

Brewer's Friend uses the term "pre-boil efficiency" for what BeerSmith (and others) call mash efficiency. It's the percentage of maximum possible extract (sugar) that the grain bill could create that makes it into the BK. Conversion efficiency measures how much of the maximum potential extract actually gets created in the mash. A good conversion efficiency is near 100%. Lauter efficiency measures the percentage of extract that was created in the mash that actually makes it into the BK. Lauter efficiency is always less than 100%, because some of the extract created in the mash always remains in the grain bed in the absorbed wort. Mash (pre-boil) efficiency is equal to conversion efficiency times lauter efficiency.

Brewer's Friend does a pretty good job calculating mash (pre-boil) efficiency, but it does not correct for the moisture content of the grain. This causes Brewer's Friend to underestimate the actual mash efficiency. However, BF does not calculate conversion efficiency correctly. The proper way to calculate conversion efficiency is presented here.

Brew on

 

[BrewZer]

Brewer's Friend uses the term "pre-boil efficiency" for what BeerSmith (and others) call mash efficiency. It's the percentage of maximum possible extract (sugar) that the grain bill could create that makes it into the BK. Conversion efficiency measures how much of the maximum potential extract actually gets created in the mash. A good conversion efficiency is near 100%. Lauter efficiency measures the percentage of extract that was created in the mash that actually makes it into the BK. Lauter efficiency is always less than 100%, because some of the extract created in the mash always remains in the grain bed in the absorbed wort. Mash (pre-boil) efficiency is equal to conversion efficiency times lauter efficiency.

Brewer's Friend does a pretty good job calculating mash (pre-boil) efficiency, but it does not correct for the moisture content of the grain. This causes Brewer's Friend to underestimate the actual mash efficiency. However, BF does not calculate conversion efficiency correctly. The proper way to calculate conversion efficiency is presented here.

Brew on

Now I know why a good brewday starts with a beer -- it makes the math a lot easier to ignore.

 

[AZ Maverick]

Brewer's Friend uses the term "pre-boil efficiency" for what BeerSmith (and others) call mash efficiency. It's the percentage of maximum possible extract (sugar) that the grain bill could create that makes it into the BK. Conversion efficiency measures how much of the maximum potential extract actually gets created in the mash. A good conversion efficiency is near 100%. Lauter efficiency measures the percentage of extract that was created in the mash that actually makes it into the BK. Lauter efficiency is always less than 100%, because some of the extract created in the mash always remains in the grain bed in the absorbed wort. Mash (pre-boil) efficiency is equal to conversion efficiency times lauter efficiency.

Brewer's Friend does a pretty good job calculating mash (pre-boil) efficiency, but it does not correct for the moisture content of the grain. This causes Brewer's Friend to underestimate the actual mash efficiency. However, BF does not calculate conversion efficiency correctly. The proper way to calculate conversion efficiency is presented here.

Brew on

OK - Thanks for that information.
I ran the math from your link using my actual BIAB kettle values and ended up with a first wort conversion efficiency of 94.7% using the approximation formula and 94.1% using the full accurate formula.
I think I now understand a bit more about the first wort conversion and efficiency measurements....

 

[pedrovic]

But in the case of BIAB, if I remove the grain bag at the end of the mash would I not be stopping the enzymatic activity of the grains?

 

[ScrewyBrewer]

I have not done a mash-out in years. In the end, the extra effort never seemed to make a measurable difference

 

[CascadesBrewer]

I have not done a mash-out in years. In the end, the extra effort never seemed to make a measurable difference

Same here.

When I moved to BIAB I was doing a mash out. It was what I did with fly sparging. I thought that maybe it would help with a little extraction, conversion, and/or head retention. It did not add too much more time and effort (I could elevate the bag and stir while adding heat). But then I started doing a lot more small batch stove top batches where it would be a pain if I wanted to lift the grain bag while heating, so I did not do mash outs for those batches. I did not really notice a difference one way or the other, so I stopped doing a mashout for my 5 gallon batches, and I did not really notice a difference.

 

[doug293cz]

But in the case of BIAB, if I remove the grain bag at the end of the mash would I not be stopping the enzymatic activity of the grains?

No. Very early in the mash, the majority of the enzymes are released into the water/wort. So, removing the grain from the wort will not stop enzymatic action. The enzymes in the wort will continue to act on long chain sugars already in the wort. What will stop is the solubilization of gelatinized starch. Thus the SG will stop increasing (if it hasn't already maxed out), but fermentability of the wort will continue increasing (unless the extract has already been reduced to fermentable sugar and limit dextrins.)

You can start heating the wort to a boil as soon as you pull the bag, and you will denature the enzymes in about the same amount of time as if you did a mash out.

Brew on

 

[cubalz]

I stopped doing a mash out about 4 years ago. Gained some time back from a long brew day and no noticable affect on efficiency