Mash-Out by infusion, decoction, or both?

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klnosaj

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I have rather low efficiency (~55%) and it's been offered that a proper mash-out might help. Am I to raise the temp to 170 through infusion, decoction, or both?

For the Special Bitter I'm brewing tomorrow I'll have a mash of 16.63 qts @ 149F. To raise that to 168 I'd have to add 19 qts of boiling water! If I add only 1 gallon of boiling water to my 16.63 qt 149F mash all I've done is raise the mash temp to 154F and that hardly seems worthwhile. I'm confused....:drunk:
 
A mash-out won't help your efficiency it's done to stop the conversion of starch to sugar. With that said, what is your grain bill? You may have a problem with your water to grain ratio.
 
This might also help, my answer to another post. Mash-out is commonly done at a temperature of 170F.

The rest temperatures for alpha and beta amylase are commonly between 149 *F (65 *C) and 165 *F (69 *C). A low temperature rest favors the beta amylase and sets the fermentbility of the wort. A high temperature rest favors the alpha amylase and completes the starch conversion. Many brewers like to use 152-154 *F (66.5-67.5*C) as their preferred mash temp as it gives a nice balance of body and fermentability that works well for British and American style ales. Temperatures closer to 133 *F (55 *C) result in more medium chained proteins (good for head retention and body).
 
This might also help, my answer to another post. Mash-out is commonly done at a temperature of 170F.

The rest temperatures for alpha and beta amylase are commonly between 149 *F (65 *C) and 165 *F (69 *C). A low temperature rest favors the beta amylase and sets the fermentbility of the wort. A high temperature rest favors the alpha amylase and completes the starch conversion. Many brewers like to use 152-154 *F (66.5-67.5*C) as their preferred mash temp as it gives a nice balance of body and fermentability that works well for British and American style ales. Temperatures closer to 133 *F (55 *C) result in more medium chained proteins (good for head retention and body).

Mash-out stops sugars from continuing to degrade and may help the sparge work more effectively at separating the fermentables from the grains. My grain ratio is fine, though maybe a little thin (I'm going down to 1.25 for this batch).

I know that mash-out is done at 170. My question is, how do I get there.
 
For decoction mash you will have to remove some of your mash and bring it to a boil then add it back. My equation came out to 5 quarts of wort that needs to be removed and boiled. Or, if possible, you can just go with direct heat.
 
For the Special Bitter I'm brewing tomorrow I'll have a mash of 16.63 qts @ 149F. To raise that to 168 I'd have to add 19 qts of boiling water! If I add only 1 gallon of boiling water to my 16.63 qt 149F mash all I've done is raise the mash temp to 154F and that hardly seems worthwhile. I'm confused....:drunk:

That 19 quart number has to be wrong - I get a bit over 7 quarts of boiling water needed to raise 16.6 quarts from 149 to 168. And if you add 1 gallon of boiling water to 16.6 quarts at 149, the temp should go up to about 161. Note - my calculations are crude and don't account for what portion of the 16.6 quarts is grain vs. wort - use a program like BeerSmith to get more exact numbers, but my numbers should be in the ballpark.
 
That 19 quart number has to be wrong - I get a bit over 7 quarts of boiling water needed to raise 16.6 quarts from 149 to 168. And if you add 1 gallon of boiling water to 16.6 quarts at 149, the temp should go up to about 161. Note - my calculations are crude and don't account for what portion of the 16.6 quarts is grain vs. wort - use a program like BeerSmith to get more exact numbers, but my numbers should be in the ballpark.

I was using BeerSmith but you're 100% correct that 1 gallon of boiling water will raise the temp to 161. I don't know why I said 154 in my OP. And you're also right of course that I wouldn't need 19 qts of boiling water. Apparently I was pretty damned tired when I wrote the first post! Thanks for pointing out the errors.

In any event, the question remains: is it routine to hit mash-out temperature by infusion or decoction or a combination. And as for infusion if I increase tempt by infusion using 7 qts I'm still using up almost half of my sprage water and that doesn't seem right.
 
In any event, the question remains: is it routine to hit mash-out temperature by infusion or decoction or a combination. And as for infusion if I increase tempt by infusion using 7 qts I'm still using up almost half of my sprage water and that doesn't seem right.

I don't think many people use decoction for mash-out. Many people don't do a mash-out at all. I usually do a mash-out, and I have two methods - which one I use depends on the particular grain bill and how much sparge water I will need. The easiest way is just to add the required amount of boiling water, but sometimes I use a heat exchanger coil in my cooler mash tun. I have 4 or 5 gallons of boiling water in my kettle and use my March pump to circulate boiling water through the coil and back to the kettle. This used to be my prechiller, but I realized it was more effective to recirculate ice water for chilling, so decided to turn this into something useful - now use for mash-out or could use for step mashes if I want to.

DSC00012.JPG

The horizontal handle rests on the lip of my 10 gallon round cooler and supports the coil just off the false bottom - the vertical handle is used to rock the coil back and forth and I can stir with a paddle in the center. Works well - the only problem is that grain sticks to the coil - not a problem for mash-out, but for step mashes, after raising the mash temperature I would probably want to knock the grain off with a brush or squirt bottle. At this point I have only used it for mash-out.
 
If it's really 55%, I think you ought to look other places to improve your efficiency.

How is your grain being crushed? What does it look like? How about your mash pH?
 
If it's really 55%, I think you ought to look other places to improve your efficiency.

How is your grain being crushed? What does it look like? How about your mash pH?

I agree 100%. I know that a mash-out isn't going to give me appreciably greater efficiency, if any improvement at all. But it seemed a good technique to add to my arsenal irrespective of whether it helps with efficiency in this particular batch. Of course, I'm still not 100% sure how it's supposed to go but I'll keep reading the advice I get here.

I crush my grain at the LHBS. I've suspected that it might not be fine enough but I've never heard anyone else complain about it there and I've asked a couple of other customers when the workers' backs were turned. And I haven't checked my ph. I know my water is pretty high out of the tap. I'll definitely look into it.

I think my biggest deficit is in precision. Up until now I've been a little too loose with measuring water volumes in particular. I've decided that today I'm going to ignore the sage advice that says "It takes homebrew to make homebrew" and not allow myself an adult beverage until after I've finished brewing. That will be the hardest part of the brewing day.
 
I use a 5G cooler mash tun. 4G of water for mash @ roughly 168 degrees (temp of water going in) hits mid to low 150's. Drain after an hour. Add 4 more gallons of ~182 degree water, hits close to 168.

Print this out, tape it to your wall, and now you are free to drink and brew at the same time. :cross:
 
My experience is that if you batch sparge, there's really nothing to be gained by doing a mashout. It will not increase efficiency measurably, and since you get to a boil so quickly there's no need to denature enzymes.

FWIW, I stopped drinking while brewing 12 years ago. If I drink, I make more mistakes and the cleanup becomes much more laborious.
 
My experience is that if you batch sparge, there's really nothing to be gained by doing a mashout. It will not increase efficiency measurably, and since you get to a boil so quickly there's no need to denature enzymes.

FWIW, I stopped drinking while brewing 12 years ago. If I drink, I make more mistakes and the cleanup becomes much more laborious.

I find that if I "sample" my previous batches of homebrew (strictly for quality purposes - haha) my cleanup after the brew sessions becomes much faster... however the next day when I have to re-wash everything... that kinda sucks. :drunk:
 
Specifically with regards to the mashout, I have done it with boiling water infusions, and I have done it with thin decoctions, and I have done it with direct heat.

If you are using a cooler and batch sparging, I have had better luck actually hitting my target temps with decoction than with extra infusions, but to each their own. I don't usually bother with an extra infusion. Although, I will do a mash out decoction if I am already doing a decoction mash, since I'll already have the equipment ready and it doesn't really add any time to the brew day.

Apart from recirculating systems, the easiest by far is if you are doing BIAB, where you can just turn on the burner and heat your mash up to the requisite temperature before pulling out the grain bag.
 
Efficiency problems can be frustrating. I batch-sparge, and while I am mashing I pop open the cooler and vigorously give it a 30 second stir every 5-10 min for the first 45 min, then let it settle for 15 min before I collect my runnings. Then when I sparge at 168-170, I stir twice in 5 min intervals, let it settle for about 10 min and then drain.

When I do the stirring, I don't even open the cooler lid up all the way so I hardly get any temp drop at all.

I feel this helps with the efficiency and always seem to end up with decent gravities.
 
If you are mashing at 149F, how long are you mashing for? I found that if I mashed for just 60 minutes at that sort of temperature, I wouldn't get complete conversion. I now mash for 90 minutes at 150F, and do get complete conversion. I also get > 85% mash/lauter efficiency with a mash out, followed by a fly sparge. Without the mash out, my efficiency drops to about 75%.
I use a mash thickness of 1 qt / lb, and for a typical brew, I need to add an infusion of about 5 qt water to bring the temperature up to the high 160's When I started doing a mash out, I thought that the increased sparge temp (high 160's vs low 150's) was responsible for the efficiency increase. I now think that the vigorous stirring of the mash out water prior to starting the sparge is the main reason for the efficiency increase.
The thick mash (recommended by Daniels and Noonan for English beers) also allows me to do a mash out, and still allows for a thorough sparge. With a thinner mash, I would need a bigger infusion for the mash out, and would not have enough sparge water to sparge as thoroughly.
I've also tried double batch sparging without a mash out, but using sufficiently hot sparge water to raise the temperature up to about 170F. This gave me about 80% efficiency (less with larger beers).

-a.
 
If it's really 55%, I think you ought to look other places to improve your efficiency.

How is your grain being crushed? What does it look like? How about your mash pH?
+2 on the crush

I've sparged with hot tap water and my efficiencies don't suffer/vary in the least.

I have two LHBS stores within 30 min of me. At the closest LHBS, I always get 78 - 80% efficiency. When he is closed and I have to go to the other shop, I consistently get around 68 - 70%. The primary difference is where I get the grain. My between-batch efficiencies are very precise.

To be honest, it's not really a big deal. I just know that I have to buy an extra pound of base malt when I have to go to the other shop.
 
The results are in!

I ended up using an infusion of ~8 qts of boiling H2O and still came up well short of my 169F target during mash-out. I compensated by using ~180F for my sparge which got the 2nd runnings up to ~167. Close enough.

I ended up with MUCH higher efficiency this time (~69%)...so much higher that I had to recalculate my hops additions which I ****ed up because....

It turns out it is impossible not to drink beer while brewing beer (at least for me...more power to those of you who can resist). I now have like a 5.8% IPA when I was aiming for a 4.6% Special Bitter. I tend not to like IPAs but hey, worse things could have happened!

Thanks to all for the suggestions and tips!
 
Efficiency problems can be frustrating. I batch-sparge, and while I am mashing I pop open the cooler and vigorously give it a 30 second stir every 5-10 min for the first 45 min, then let it settle for 15 min before I collect my runnings. Then when I sparge at 168-170, I stir twice in 5 min intervals, let it settle for about 10 min and then drain.

When I do the stirring, I don't even open the cooler lid up all the way so I hardly get any temp drop at all.

I feel this helps with the efficiency and always seem to end up with decent gravities.

You "feel" it helps with efficiency, but have you ever checked? I average 80-85% efficiency without all that rigamarole.
 
You "feel" it helps with efficiency, but have you ever checked? I average 80-85% efficiency without all that rigamarole.

I have checked. I typically get in the mid to upper 70%'s with this process, whereas when I started AG I was in the 60%'s without the stirring. But I've tweaked a few other things such as water ratios that may have also helped with my efficiency. So maybe a combo of each...

Who knows, but I would hardly calling stirring rigamorale...and when it comes to brew day I can't just sit still for a whole hour while the mash cooks. I think there are other people that have reported better efficiencies when they stir while mashing/sparging. If you don't need do to it, then more power :rockin: to ya!
 
I don't sit around waiting for the mash. I clean the house, do laundry, cook, bake bread....all that happens for me when I stir the mash is that I lose heat by opening the cooler.
 
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