Boiling Down Leftover Runnings

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ultravista

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Who here boils down leftover runnings?

I mash in a bag and often have a few quarts of wort after sparging. I put an upside down colander in a bucket and put the bag right on top.

After two minutes or so, and with a little light compression, I can get another three qaurts or so.

When making an outmeal stout yesterday, I collected 3 quarts and boiled it down to a quart (on the stove) while the kettle was doing it's thing.

The collected runnings were 1.045 and after condensing, 1.085.

I dumped it into the kettle and it brought my OG up a couple of points. It was very tastey.

Anyone else do something similar? If so, what have your results been?
 
I have thought about this a few times, on a bit of a larger scale however. On a ten gallon batch spargeI've wondered if I could pull one more run and boil down to get a low to mid range starting gravity and ferment to see what I end up with. I'm not too worried about tannins due the fact I don't mash out, and I'm also not worried about volume. It is what it is.


I'm interested enough to give it a shot on my next brew.

If I end up with something in the realm of a couple gallons, might be worth the experiment.
 
I have thought about this a few times, on a bit of a larger scale however. On a ten gallon batch spargeI've wondered if I could pull one more run and boil down to get a low to mid range starting gravity and ferment to see what I end up with.

This is parti-gyle, no?
 
This is parti-gyle, no?

Well, technically I suppose it is. When I thought about this last was on a modified parti-gyle I brewed. I started with a schwarzbier, ran it off then added a few lbs of grain and some cereal mashed oatmeal to get an oatmeal stout. My temp came in a bit low, so by the time I added enough boiling water to raise it up, I was basically at full water volume for my boil.

I then had the idea that I could probably sparge and still get some wort out of the tun, since what I had accomplished was essentially a no sparge. I just felt like I was leaving some sugar behind and I hate to waste resources!

I also hate making crappy beer, but it may have been worth a shot to get a 3 gal batch of mild perhaps?
 
I'm not too worried about tannins due the fact I don't mash out

I had a big problem with tannins in one that I tried this way. Not technically a parti-gyle, or at least, not planned. I fly sparge with 180 degree water. I left the tun full, finished my boil, then drained the tun and made a beer we were calling "backwash ale." It came after a stout, so it was pretty dark itself - more brown than anything else. It's tasted like tannin and monkey grundle every time I open one. I've been hiding them in the basement for months now - I'd pitch the whole batch if I new exactly which ones they were.

What do you mean, you don't 'mash out.' The terms surrounding all grain, especially the sparge part, have for whatever reason never stuck in my mind. Why, also, are you dodging tannins by not mashing out?
 
I batch sparge and I'm not mashing out, as in I dont raise my mash above 170. It's my understanding anything north of that will potentially extract tannins. I actually keep my grainbed around the same temps that I sac rest at usually.

Tannins can also be extracted if pH levels raise over 6 I think. That could be a problem for me I suppose, I don't test my pH most times.

This last batch I did was basically a no sparge, so I felt as if I could sparge once just to rinse the grain and maybe end up with a wort that's workable.

I could well be wrong, but on my next double batch I believe I'll give it a shot to find out.
 
Maybe I should rephrase a prior comment in that as far as temperature is concerned I'm not worried about tannins.
 
I batch sparge and I'm not mashing out, as in I dont raise my mash above 170. It's my understanding anything north of that will potentially extract tannins. I actually keep my grainbed around the same temps that I sac rest at usually.

Tannins can also be extracted if pH levels raise over 6 I think. That could be a problem for me I suppose, I don't test my pH most times.

This last batch I did was basically a no sparge, so I felt as if I could sparge once just to rinse the grain and maybe end up with a wort that's workable.

I could well be wrong, but on my next double batch I believe I'll give it a shot to find out.

This sounds like a great experiment. Especially if you're using enough grain and essentially doing a no sparge, you should be able to get at least a good three gallon batch out of it. You could also just throw in a couple of lbs of specialty grains away you go.
 
This sounds like a great experiment. Especially if you're using enough grain and essentially doing a no sparge, you should be able to get at least a good three gallon batch out of it. You could also just throw in a couple of lbs of specialty grains away you go.

I have done 10 gal batches, then backed up with another 5. I usually add a few lbs of grain before the last batch but this thread peaked my interest. I usually end up low in gravity on the last one even after the grain addition, so I thought I could just boil longer and just get a smaller last batch.

In my addition of base grain I usually add a bit of specialty as well. I'll probably do the same as before, just shoot for 3 gallons instead of 5. Lawnmower beer!
 
If high grain temperatures caused tannin extraction then decoction mashes would not exist. The tannins come from the high pH as the enzymes that act as pH stabilizers are rinsed away during excess sparging. Highly kilned malts also possess pH lowering due to the toasting of the kernel that keeps tannin extraction at bay.

Personally, I just add the residual runoff directly to my boil pot.
 
If high grain temperatures caused tannin extraction then decoction mashes would not exist. The tannins come from the high pH as the enzymes that act as pH stabilizers are rinsed away during excess sparging. Highly kilned malts also possess pH lowering due to the toasting of the kernel that keeps tannin extraction at bay.

Personally, I just add the residual runoff directly to my boil pot.

The decoction point you make seems reasonable, I wonder if there are tannins extracted. I'll have to study up on that. My thought is that they are in fact extracted but since there is maillard reaction going on, maybe its muted? Also usually decoctions are only a small portion of the grain bill, not the entire mash.

If the entire grainbed gets too warm I think tannins would make up a much higher percentage of the runoff, thus making them more pronounced.

This is all just my speculation of course, I'll read up on decoctions.

I do agree with your pH info, and that's something I should probably measure on these crazy batches I sometimes make. :mug:
 
"Homebrewers used to infusion mashing may wonder how a decoction could be boiled without extracting a large amount of tannins and yielding a very astringent beer. After all, when lautering, they are repeatedly told that their grain bed temperature should never exceed 170 °C (77 °C). The key to understanding this apparent discrepancy is understanding when tannins are soluble in wort. Increased heat and increased pH both favor tannin extraction. At lower pH values, such as those found in a thick mash, tannin extraction from grain husks is minimal even at boiling temperatures. At higher pH values — such as those in a grain bed that has been extensively sparged — excess tannin extraction occurs at a much lower temperature.

Decoction mashing inactivates some of the enzymes in a mash. Enzymes are proteins (strings of amino acids) that are folded into a specific three-dimensional shape. The shape of the enzyme determines its function. When heated, enzymes unravel (or denature, in the lingo). Different enzymes denature at different temperatures because they assume different shapes and some are “cross-linked” by sulphur bridges that stabilize their structure. Boiling temperatures are sufficient to denature almost all enzymes and thus boiling the mash inactivates any enzymes that are useful in brewing. In decoction mashing, only roughly a third of the mash is boiled at each decoction and enzymes from the unboiled mash compensate for those denatured in the decoction boil.

Besides boiling of a portion of the mash, decoction mashing involves a lot of stirring and can result in an increased yield for many brewers. In a home brewery, a decoction mash is likely to give the brewer a better yield compared to an unstirred single infusion mash. My efficiency typically jumps by around 5% when I decoct."

Taken from a byo article. Here's the link to it http://***********/stories/techniques/article/indices/45-mashing/541-decoction-mashing-techniques
 
Also usually decoctions are only a small portion of the grain bill, not the entire mash.

Maybe so, but then you would have to justify a "triple decoction." At what point is no longer a "small" portion of the grain bill?
 
"
Decoction mashing inactivates some of the enzymes in a mash. Enzymes are proteins (strings of amino acids) that are folded into a specific three-dimensional shape. The shape of the enzyme determines its function. When heated, enzymes unravel (or denature, in the lingo). Different enzymes denature at different temperatures because they assume different shapes and some are “cross-linked” by sulphur bridges that stabilize their structure. Boiling temperatures are sufficient to denature almost all enzymes and thus boiling the mash inactivates any enzymes that are useful in brewing. In decoction mashing, only roughly a third of the mash is boiled at each decoction and enzymes from the unboiled mash compensate for those denatured in the decoction boil.
Not mentioned is that the enzymes are in the liquid, not so much the solid of the mash. When decocting it is important to pull a generous amount of grain while leaving the liquor-- and thus the enzymes- behnd.
 
Not mentioned is that the enzymes are in the liquid, not so much the solid of the mash. When decocting it is important to pull a generous amount of grain while leaving the liquor-- and thus the enzymes- behnd.

Right! And when the decoction is returned to the tun, all the enzymes left in there can go continue to work. The enzymes denatured during the decoction is kept minimal, since most were left behind in the first place. That's why balanced grainbills are important, to make sure there's enough buffering power left in the bulk of a mash.

What I was referring to however is while I'm batch sparging my first beer, I run off and sparge only once. Then I add some grain to the tun, sac rest again with enough volume to no sparge for my second beer.

If I decide to sparge, after collecting enough wort for a full boil on beer number 2, I feel I can get a few more gallons to make a small batch of small beer without worrying about tannins.

My reasoning is this, I haven't sparged the crap out of my grain yet, and I also haven't raised the grainbed over 170. Also, I have some 'fresh' grain in there, with fresh and active enzymes ready to go to work.

I have pulled a third beer a few times before, without a tannin problem. The problem I did have consistently was low gravity. So if I boil longer on beer 3, I can evap more water and get my gravity at the expense of volume.

I don't decoct when I do this method, if I did who knows? Possibly I could get tannins.

The reason I brew this way sometimes is to get more bang for my buck in terms of time spent brewing. I can get 2 awesome beers @ five gallons each and a third mild at around 3 gallons and it takes Mr about an hour and a half longer than a single 5 gallon batch.

With a baby and 2 older kids, my time is very expensive. Lol

I need to make the most of it, and so far, its working out very well for me.
 
I routinely sparge until I get to boil volume, the continue until the runnings are no longer sweet. I use those second runnings as smaller, experimental batches (10l ~2.64gal), mainly using herbs, spices, wild hops picked while hiking etc. If OG is not high enough, I add some honey or similar stuff at appropriate times during the boil. Worked out well so far.
 
Do you get any tannin extraction that you notice from sparging to such a low gravity? Most fly sparging is supposed to stop at the 1.015 mark right?
 
cooper said:
Do you get any tannin extraction that you notice from sparging to such a low gravity? Most fly sparging is supposed to stop at the 1.015 mark right?

This is news to me. I guess I wouldn't notice a lot of residual sweetness at 1.015 after successively tasting wort that's less and less sweet though. I think I might actually take a reading next time. No tannin taste I could discern. However, I mash out and then let the sparge water cool down a bit (read: I take the pot containing the sparge water from the stove), maybe to sacc rest temp. It was my understanding that lower temperatures can help reduce tannin extraction. Also, I use what is described as "hybrid" method in the AG forum (don't know how to make a link on my phone, but the thread describing the technique is a sticky). This makes temp control in the grain bed during sparging difficult and I suspect that it is relatively low.
 
they say to stop sparging when you get to 1.010 running off. This is moreso tailored to fly sparging. Using batch sparges, even with SLOW runoff, I've never gotten to 1.010.
 
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