BIAB Mashing Out

HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.

Help Support Homebrew Talk:

CarolinaMatt

Well-Known Member
Joined
Nov 14, 2014
Messages
147
Reaction score
19
I use a roller mill with a .025" gap, and yes there's a fair amount of flour.

Make getting a mill a priority. Your efficiency will increase, and you can buy/store grain in bulk without worry of it going stale, since you'll be able to crush it whenever you need it.
Good deal! I have looked at a low entry cost for something like that such as a corona mill. I know it's not as big and bad as other options, but for around $30 with a corona mill can I accomplish the finer crush?
 

Oginme

Well-Known Member
Lifetime Supporter
Joined
Apr 13, 2013
Messages
1,926
Reaction score
880
Absolutely! The much maligned Corona-type mills can do an excellent job at producing a very good crush with a minimum of flour all the way up to making it all flour.
 

dwightr8

Well-Known Member
Joined
Aug 22, 2010
Messages
63
Reaction score
20
Location
Lyndale, WA
I shared my results. Throwing shade on other home brewers doesn't make this site a more inviting place to visit.
Sorry for the snarky remark John. It certainly didn't add anything to the thread. Please accept my apology.
 

CarolinaMatt

Well-Known Member
Joined
Nov 14, 2014
Messages
147
Reaction score
19
Absolutely! The much maligned Corona-type mills can do an excellent job at producing a very good crush with a minimum of flour all the way up to making it all flour.
Great to hear! Trying to keep costs in check lately with first little one arriving any day. I'll try to configure it to run on a drill.
 

shetc

Well-Known Member
Joined
Jul 28, 2013
Messages
2,056
Reaction score
1,472
Very interesting data points. Looks like anywhere from 2 points to 10 points, but a bunch of different processes as well.
I mash out based on this information, and I usually hit my predicted OG. I could change my malt bill instead but I'm not really in a hurry on brew day anyway.
 
Joined
Dec 26, 2013
Messages
3,037
Reaction score
2,758
I had stopped the mash out step as the most I ever got was 2 points, but like shetc says, I'm not in a hurry. May try again.
 
Joined
Dec 26, 2013
Messages
3,037
Reaction score
2,758
So just for a private test, I am brewing a Pilsner this morning that calls for pre-boil gravity of 1037 at 70% mash efficiency.
At 60 minutes I was at 1040
I made a quick run for ice but was only gone 10 min at most.
Bumped temp to 168 and was at 1044 (This may be a combo of longer mash and bump in temp)
After sitting for 10 minutes at the higher temp .. still 1044
 
Last edited:

Fewk

Member
Joined
Dec 2, 2017
Messages
22
Reaction score
17
I also lift my bag out and start heating my wort at the same time, and have had consistent results and beers that I’ve been stoked about (i.e. way tasty).
 

John Burns

Member
Joined
Apr 9, 2018
Messages
12
Reaction score
0
I always leave the bag in the kettle until I reach mash out temp, then pull and drain while raising to boil. I have been getting good efficiency/conversion doing this.
I always leave the bag in the kettle until I reach mash out temp, then pull and drain while raising to boil. I have been getting good efficiency/conversion doing this.
I've been very curious about this approach as well. I do BIAB method. How does raising the temp to 170F improve efficiency? Does it cause the alpha amylase enzymes to increase in productivity because they usually work at higher temperatures. Just curious. Would like some insight behind the method. Thanks!
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
Lifetime Supporter
Joined
May 14, 2014
Messages
10,183
Reaction score
6,208
Location
Renton
I've been very curious about this approach as well. I do BIAB method. How does raising the temp to 170F improve efficiency? Does it cause the alpha amylase enzymes to increase in productivity because they usually work at higher temperatures. Just curious. Would like some insight behind the method. Thanks!
If you don't get complete conversion of starch to sugar within the allotted mash time, a mash out can sort of supercharge the completion (at least until the amylase enzymes are completely denatured.) The limiting step in conversion is gelatinization of of the starch, as the enzymes cannot act on un-gelatinized starch. Gelatinization proceeds from the surface of the grits towards the center, and the larger the grit, the longer this takes. With the very fine crushes that can be used with BIAB, gelatinization can occur much more quickly, and with fine enough crushes mash outs provide no benefit. Some malts can also have starch with higher gelatinization temps, and if you have any of these, they may not completely gelatinize during the mash. A higher temp rest can gelatinize more of these stubborn starches, thus improving your conversion efficiency.

Net: If conversion is complete at the end of the mash, a mash out will not increase your efficiency. If conversion is incomplete, then a mash out is likely to increase your efficiency.

Brew on :mug:
 

fendersrule

Well-Known Member
Joined
Oct 11, 2018
Messages
566
Reaction score
233
Doug is spot on.

It’s probably faster to try a 90 minute mash vs a 60 min + mash out as a first step.

It’s far less work at least.

if you can pick up 5% more efficiency with a 30 minute longer mash time, that could be very well worth it.
 

wsmith1625

Well-Known Member
Joined
Aug 14, 2014
Messages
210
Reaction score
91
Location
Manchester, NJ
My last few batches I have been getting low final gravity readings. First batch that had this problem I was using my original dial thermometer to get strike and mash temp readings. I thought I was dead on, but then took a mash temp reading with my LavaTools PT-09 and realized I was off. After brew day, I calibrated my dial thermometer and realized that I mashed too low.

For my next brew, I bought a ThermoWorks RT610B-12 thermometer for strike and mash temps. Checked the calibration when I received it and it was right on. I thought this would solve my low FG issues.

I do BIAB brewing and wrap the brew kettle in blankets to hold the mash temperature. My typical temperature drop is only 2 degrees in 60 minutes. I'm very happy with that and don't plan on changing anything there.

The last batch I brewed was an expect 1.012 and I finished at 1.008. I'm fairly confident my mash temperature was good and I don't see any signs of infections in any of my brews. I started thinking about doing a mash out. I did read this thread and see that most agree it's not necessary. I don't sparge or mash out, I simply pull the bag and let it hang over the brew kettle while I bring the wort to a boil.

What occurred to me is that the grain in the bag is slowly cooling as it drips into the brew kettle. As the grain is hanging and temperatures are dropping, am I getting additional fermentable sugars that I don't want? Should I do a mash out and then pull the bag to see if I get better results?
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
Lifetime Supporter
Joined
May 14, 2014
Messages
10,183
Reaction score
6,208
Location
Renton
My last few batches I have been getting low final gravity readings. First batch that had this problem I was using my original dial thermometer to get strike and mash temp readings. I thought I was dead on, but then took a mash temp reading with my LavaTools PT-09 and realized I was off. After brew day, I calibrated my dial thermometer and realized that I mashed too low.

For my next brew, I bought a ThermoWorks RT610B-12 thermometer for strike and mash temps. Checked the calibration when I received it and it was right on. I thought this would solve my low FG issues.

I do BIAB brewing and wrap the brew kettle in blankets to hold the mash temperature. My typical temperature drop is only 2 degrees in 60 minutes. I'm very happy with that and don't plan on changing anything there.

The last batch I brewed was an expect 1.012 and I finished at 1.008. I'm fairly confident my mash temperature was good and I don't see any signs of infections in any of my brews. I started thinking about doing a mash out. I did read this thread and see that most agree it's not necessary. I don't sparge or mash out, I simply pull the bag and let it hang over the brew kettle while I bring the wort to a boil.

What occurred to me is that the grain in the bag is slowly cooling as it drips into the brew kettle. As the grain is hanging and temperatures are dropping, am I getting additional fermentable sugars that I don't want? Should I do a mash out and then pull the bag to see if I get better results?
If you start heating your wort as soon as you pull the bag, that is pretty much equivalent to heating the wort to mash out prior to pulling the bag, as far as the effect on wort fermentability. If the wort that drains slowly from the bag over time actually is more fermentable, it's a small fraction of the total wort volume, so will have minimal effect on the fermentability of the total wort volume.

If you want to try something that might actually "quench" the enzyme action, calculate how much boiling water you need to raise your mash to 170, withhold it from the mash, and add at the end of the mash to raise the temp to mash out "instantly."

Brew on :mug:
 

Bobby_M

Vendor and Brewer
HBT Sponsor
Joined
Aug 3, 2006
Messages
24,713
Reaction score
3,371
Location
Whitehouse Station
Running the full volume up to 160 for a few minutes, then ramp to 170 will boost conversion efficiency by a measurable amount and it happens faster than the same rest at say 155. It is LIKE a mash out process wise but for a different purpose.
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
Lifetime Supporter
Joined
May 14, 2014
Messages
10,183
Reaction score
6,208
Location
Renton
Running the full volume up to 160 for a few minutes, then ramp to 170 will boost conversion efficiency by a measurable amount and it happens faster than the same rest at say 155. It is LIKE a mash out process wise but for a different purpose.
This is true, unless the conversion is already at 100%, which is often the case with very fine crushes. It can be especially useful if you have malt that has some fraction of starch granules with higher gelatinization temp. Not all grain is like this, and I don't think it's easy to find data on the grain that indicates if it does or not (unless you can get the DSC curve for the gelatinization temp test, which will have a big lower temp hump, and a smaller higher temp bump. Look at the left curves, the right ones are for a rerun.)

Differential-scanning-calorimetry-thermograms-of-prime-starch-from-nonwaxy-high-amylose.png


Brew on :mug:
 

Bobby_M

Vendor and Brewer
HBT Sponsor
Joined
Aug 3, 2006
Messages
24,713
Reaction score
3,371
Location
Whitehouse Station
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.
 

wsmith1625

Well-Known Member
Joined
Aug 14, 2014
Messages
210
Reaction score
91
Location
Manchester, NJ
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.
 
Top