Maximizing Efficiency when Batch Sparging

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I have skimmed over this thread looking for clarification on the following but didn't find it, apologies in advance if i missed it:

When batch sparging, i understand it is preferable to leave the grain bed in tact, but it seems to me that stirring and just adding an extra vorlauf cycle would increase my already lousy efficiency. Is this accurate? I saw one guy on brewing TV talk about skipping vorlauf all together because it doesn't really impact the end result. I agree that it falls out in trub anyway.

I guess my question is, if you aren't worried about vorlaufing, would it increase my efficiency to stir the whole mash in batch sparges? (I'm sparging at 170 degrees)

You definitely can stir your sparge water in a batch sparge setup. In fact, I think you should, and I didn't realize there were people recommending not to. The vorlauf will reset the bed.

I'm suspect you'd be fine if you skipped the vorlauf, though it's a pretty easy thing to do so I don't know what you'd gain by skipping it.
 
Thanks for the reply! I guess when you read brewing forums as much as i do you begin to get conflicting info. My issue with vorlauf is that it seems to be superfluous (for me) and I am constantly trying streamline my brew process. I've read plenty of conflicting threads on that as well. Thanks again.
 
Chromebrew said:
Thanks for the reply! I guess when you read brewing forums as much as i do you begin to get conflicting info. My issue with vorlauf is that it seems to be superfluous (for me) and I am constantly trying streamline my brew process. I've read plenty of conflicting threads on that as well. Thanks again.

Glad it was helpful.

I don't love the idea of boiling a bunch of husk material, which is why I'd probably stick with the vorlauf, but I suspect it's not a huge deal either way.
 
I have skimmed over this thread looking for clarification on the following but didn't find it, apologies in advance if i missed it:

When batch sparging, i understand it is preferable to leave the grain bed in tact, but it seems to me that stirring and just adding an extra vorlauf cycle would increase my already lousy efficiency. Is this accurate? I saw one guy on brewing TV talk about skipping vorlauf all together because it doesn't really impact the end result. I agree that it falls out in trub anyway.

I guess my question is, if you aren't worried about vorlaufing, would it increase my efficiency to stir the whole mash in batch sparges? (I'm sparging at 170 degrees)

Yes, you very much need to stir in the sparge water.
 
You'll bite? I didn't realize I was fishing. :p

The short answer is that you've got to figure out the total extracted sugars in your grains and then divide that by your total strike water. If you've got, for example, ten pounds of two-row at 35 points per pound per gallon and you strike with 6 gallons, you'd expect your first runnings to be (10 * 35 ppg / 6 gallons = 58 points, or 1.058). If you're significantly below that, you've got conversion problems.

Kaiser's got a comprehensive worksheet at his website: http://braukaiser.com/wiki/index.php?title=Troubleshooting_Brewhouse_Efficiency

As for the other stuff, it depends. The water to grist ratio shouldn't effect your conversion, but if there's more grain it will absorb more water, which means you're leaving sugars behind. Big beers tend to have lower efficiency on most systems. Some report that sparge temperature matters, though I'm skeptical. At the very least, I often sparge with cold water and notice no effects.

When I was first trying to sort out the efficiency issues a few months ago, I created a little spreadsheet that shows me what the actual extraction rate would be for each type of grain based on its potential, rather than simply using averages. If I can develop a predictable efficiency rate for my system, I should be able to use this tool to predict how much of each type of grain I need to create the OG I want.

Thanks for Kai's link. I've skimmed through it, and I can see that I've already done a lot of his suggestions, eg, calibrating water volumes, normalizing temperatures to 68 F when taking measurements, etc. I will study it more closely as I have time.

Really appreciate all the input. Good discussion for many of us; I hope all you veterans don't find it tiresome. I'm learning a lot!
 
You'll bite? I didn't realize I was fishing. :p

The short answer is that you've got to figure out the total extracted sugars in your grains and then divide that by your total strike water. If you've got, for example, ten pounds of two-row at 35 points per pound per gallon and you strike with 6 gallons, you'd expect your first runnings to be (10 * 35 ppg / 6 gallons = 58 points, or 1.058). If you're significantly below that, you've got conversion problems.

Kaiser's got a comprehensive worksheet at his website: http://braukaiser.com/wiki/index.php?title=Troubleshooting_Brewhouse_Efficiency

As for the other stuff, it depends. The water to grist ratio shouldn't effect your conversion, but if there's more grain it will absorb more water, which means you're leaving sugars behind. Big beers tend to have lower efficiency on most systems. Some report that sparge temperature matters, though I'm skeptical. At the very least, I often sparge with cold water and notice no effects.

Are you sure you are using the ppg method correctly? Something seems off here. For instance, I recently mashed

50lbs/22.7kg of malt that is 37ppg/80%DBFG in

16gal/60.8L water

By your method, I should be getting

50*37/16 = 116 points, or 1.116 gravity.

With kaiser's method, (or just using his chart), I see that at

60.8/22.7 = 2.7L/kg

I should be getting 1.093 gravity. 1.093 gravity is what I actually get.
 
Are you sure you are using the ppg method correctly? Something seems off here. For instance, I recently mashed

50lbs/22.7kg of malt that is 37ppg/80%DBFG in

16gal/60.8L water

By your method, I should be getting

50*37/16 = 116 points, or 1.116 gravity.

With kaiser's method, (or just using his chart), I see that at

60.8/22.7 = 2.7L/kg

I should be getting 1.093 gravity. 1.093 gravity is what I actually get.

Oops, you're right. I didn't account for the volume increase resulting from the sugar addition. Good catch. :mug:
 
Are you sure you are using the ppg method correctly? Something seems off here. For instance, I recently mashed

50lbs/22.7kg of malt that is 37ppg/80%DBFG in

16gal/60.8L water

By your method, I should be getting

50*37/16 = 116 points, or 1.116 gravity.

With kaiser's method, (or just using his chart), I see that at

60.8/22.7 = 2.7L/kg

I should be getting 1.093 gravity. 1.093 gravity is what I actually get.

Hmmm? I assume you get about 80% efficiency? 116*.8 = 92.8

EDIT: N/m you're talking about first runnings.
 
Yup first runnings - checking the conversion eff. I actually didn't even do a boil - froze the 20gal batch (2x 10gal. runnings) for use in making starters! :)
 
So I've been plagued with bad efficiency my entire all grain brewing life (3 years or so). Its never been a huge problem as I would sometimes compensate by adding extra grains to fix it and as long as I was in the range I would be fine. But now I really want to tackle the problem as its getting worse.

I recently upgraded my equipment to include a blichmann 15 gallon boil kettle, a separate hot liquor tank and my existing converted igloo cooler with a SS braid. I always thought it was me missing my volumes. I would tweak beersmith but it would always be too much wort leftover after the boil. With the new blichmann I use the sight glass so I can monitor my volumes throughout the whole process.

I made an imperial IPA which according to beersmith at 75% efficiency would give me a starting OG of 1.093 (although according to the "official" recipe it should have been 1.080, which is another puzzler). Well, I ended up with 1.062! That’s a horrifyingly low 50% efficiency. So now my great double IPA with 100 IBU's is going to be a regular IPA, but hopped as a double, throwing the whole thing off. I hit all my temps, stirred vigorously to avoid doughballs, used the beersmith recommended mash and sparge volumes (the and even extended the mash by about 15 minutes to be sure. I mashed at about 152 as I wanted a thinner, more fermentable wort. I may have ended up with a bit more Wort, but maybe 5.25 gallons instead of just 5, which doesn't make a huge impact on gravity.

As to what could be causing it I figure there are only two variables it could be: My crush and my mashtun.

As for my crush I did what I usually do, which have the company crush it for me, in this case it was Austin Homebrew. I've heard that letting the HBS crush it can hurt as they are usually conservative with their crush so customers don’t get stuck sparges, but I can't imagine that would lead to a drop in efficiency that dramatic, so while it may be the crush for part of it the main culprit has to be my mashtun

My mashtun is a converted Igloo cooler with a SS braid and a simple batch sparge. I've had it for almost three years and it's served me well, albeit getting a bit banged up. The Braid has compacted a bit but I still get good flow. When I empty the spent grains there's always liquid in the bottom but I figure that's just from the deadspace (which is supposedly accounted for in my beersmith equipment setup)

I am torn between retrofitting my cooler with a false bottom or buying a new pot and turn it into a mashtun with a false bottom and a sparge arm so I can recirculate during the mash, which my homebrew club friends say gives you much better efficiency and clearer wort. I've always liked the dump it in and forget it aspect of the cooler mashtun and have never been keen on the idea of babysitting a pot to watch my temps during the whole mash process.

Sure I could keep some DME on hand to bring up gravity to compensate, but I like IPA's and its hard to make on the fly changes like that as it makes me change my hop addition times, and affects IBU's, plus I never know how much I'm off and it’s a pain. Also, I just want to be able to get it RIGHT. I'd love any advice you guys can give me. Below is my beersmith printout which I followed to the letter.

Water Prep
Amt Name Type # %/IBU
5.25 gal Washington, DC Water 1 -
8.00 g Gypsum (Calcium Sulfate) (Mash 60.0 mins) Water Agent 2 -
4.00 g Calcium Chloride (Mash 60.0 mins) Water Agent 3 -

Mash or Steep Grains
Mash Ingredients
Amt Name Type # %/IBU
14 lbs Pale Malt (2 Row) US (2.0 SRM) Grain 4 77.8 %
3 lbs Munich Malt (9.0 SRM) Grain 5 16.7 %
1 lbs Caramel/Crystal Malt - 20L (20.0 SRM) Grain 6 5.6 %

Mash Steps
Name Description Step Temperature Step Time
Mash In Add 25.70 qt of water at 162.2 F 152.0 F 60 min

Batch sparge with 2 steps (Drain mash tun, , 4.21gal) of 168.0 F water
Boil Wort
Add water to achieve boil volume of 7.63 gal
Estimated pre-boil gravity is 1.076 SG
Boil Ingredients
Amt Name Type # %/IBU
1.75 oz Summit [17.00 %] - Boil 60.0 min Hop 7 71.0 IBUs
1.05 Items Whirlfloc Tablet (Boil 15.0 mins) Fining 8 -
0.75 oz Centennial [10.00 %] - Boil 15.0 min Hop 9 8.9 IBUs
0.25 oz Summit [17.00 %] - Boil 15.0 min Hop 10 5.0 IBUs
1.00 oz Amarillo Gold [8.50 %] - Boil 5.0 min Hop 11 4.0 IBUs
1.00 oz Palisade [7.50 %] - Boil 5.0 min Hop 12 3.6 IBUs
0.25 oz Centennial [10.00 %] - Boil 5.0 min Hop 13 1.2 IBUs
 
I don't have time for a very detailed reply, plus there's a TON of info in this thread on things to check, but here are some quick things that might not be readily thought of:

Your crush - if it you're getting it from various suppliers all the time, your crush will vary as well and therefore your efficiency. This is one nice thing about getting a mill so you can keep that constant. This probably doesn't account for your 50% efficiency though...

Your pH - since you're adding brewing salts I'm assuming you have a good idea of YOUR water profile. What I mean by that is you've tested the water coming out of your tap as opposed to a general profile for a large area. If your mash pH is out of whack it can affect your ability to convert starches to sugars and therefore your efficiency.

Your equipment - have you double checked your thermometers lately to make sure you're really mashing at 152 and not 158 for instance?

Your volumes - I've struggled with this in the past as well, and BeerSmith is no help in this area although I love the program. One thing that tips me off to this being at least part of the issue is your comment about entering the recipe and being so far off the calculated / expected OG. Below are my notes on using BS. Note that I target 6 gallons at the end of the boil.

  1. Set batch volume to 6 gallons with no trub / chiller loss
  2. ignore the fact that BS *** defines batch volume as what goes into the fermenter ***
  3. BS calculates a value in the loss to trub section as an increase in the boil volume and doesn't factor that as diluting your wort.

To this end, with the steps above you're essentially taking that quirkiness out of BS.

Also, you'll want to double check your equipment settings for your boil off rate and make sure it matches what you're typically seeing on brew day. Tied to that, you'll want to see whether you have the "Calc boil volume" box checked in your recipe which is going to factor in that boil-off (and as seen above trub losses) into the starting boil volumes.

The nice thing here is that you can copy a recipe and then play around with those settings to see how all these things affect the calculations. It takes a bit, but once you have BS set up to match your process and equipment performance (and account for they way it calculates things) it really does work great.

Another thing - for the OG in the recipe not matching BS, double check your entry of grains and assumed efficiency and boil-off. Most recipes assume a given efficiency (generally 70%) and also assume a 1 gal / hr boil off rate. Those two things alone if not represented during initial recipe entry can throw it off. I work to make sure the recipe is close in OG (within 2-3 points) and bitterness (within 5 or so IBU - make sure to pick the right formula!) with a generic equipment setting first that matches their assumptions. That way I know it's entered right. Then I pick my equipment which will change the efficiency and other variables and throw things off a bit. I then can work to up the grain or whatever to get it back in line with the target recipe and at that point it's now tailored to my system.

Also - one last thing. Another "quirky" thing I found with BS is that if you change your equipment profile any recipes using that profile are not automatically updated. You'll need to pick another equipment profile in that recipe and then change it back for it to reflect the changes. This actually makes sense since past recipes / brew days stay reflective of the equipment used at that time. Something to take into consideration though if you're playing around with your equipment profile. As a tip, you could set up a copy of your existing profile and label it something obvious so you can toggle back and forth between profiles to see the effect it has on a given recipe.
 
eddiebosox, with that kind of efficiency, I'm 99% certain that your main problem is the crush. The other things mentioned can also be factors, but considering your efficiency I wouldn't mess with anything else until you get a better crush.
 
My PH was a little low when i tested it during the mash, like around 4.8 or so. i adjust according to my DC water profile that's posted online and from what other homebrewers in the area do as well.

I check my thermometers fairly regularly but i do it from boiling water which can vary, ill try it again tonight in slushly water to see if i can hit 32.

I set my boil off rate when i got my new burner and kettle just so i could get the measurements right in beersmith. Their equipment profiles are maddening. When you say you enter things with a " generic equipment setting", which one do you use? I use the 15 gallon kettle and igloo cooler which is pretty much what i have, but my volumes were never right so i would tweak it and tweak it, and it just seemed to get even more out of whack.

I settled on just measuring my wort at the beginning and, knowing my boil off rate, adjust my boil time to get down to 5.5 gallons at the end of the boil. But sometimes that would mean a longer boil and if its something like a wit i dont want to get too much malliard reaction in that to screw up the style, plus the changes to hop additions.
 
My PH was a little low when i tested it during the mash, like around 4.8 or so. i adjust according to my DC water profile that's posted online and from what other homebrewers in the area do as well.

I check my thermometers fairly regularly but i do it from boiling water which can vary, ill try it again tonight in slushly water to see if i can hit 32.

I set my boil off rate when i got my new burner and kettle just so i could get the measurements right in beersmith. Their equipment profiles are maddening. When you say you enter things with a " generic equipment setting", which one do you use? I use the 15 gallon kettle and igloo cooler which is pretty much what i have, but my volumes were never right so i would tweak it and tweak it, and it just seemed to get even more out of whack.

I settled on just measuring my wort at the beginning and, knowing my boil off rate, adjust my boil time to get down to 5.5 gallons at the end of the boil. But sometimes that would mean a longer boil and if its something like a wit i dont want to get too much malliard reaction in that to screw up the style, plus the changes to hop additions.

I don't plan on a constant boil off rate, as it can vary depending on the weather conditions (most recently for me, in VT, is lowered heat output due to freezing propane tanks). I kill the boil briefly at 30 and 15 minutes to check my liquid levels (I have a sight glass, but you could calibrate a stick to measure where you're currently at.) so I can adjust the heat output of my burner. That's something to consider.
 
I don't plan on a constant boil off rate, as it can vary depending on the weather conditions (most recently for me, in VT, is lowered heat output due to freezing propane tanks). I kill the boil briefly at 30 and 15 minutes to check my liquid levels (I have a sight glass, but you could calibrate a stick to measure where you're currently at.) so I can adjust the heat output of my burner. That's something to consider.

My blichmann has a sightglass that has helped immensely and i watch it throughout the boil and do math in my head as to where I am in regards to how much ill lose in the hour boil. This last one was fairly consistent.

Another thing, the fermentation is very vigorous. Although thats probably becasue i pitched the yeast expecting a 1.080 gravity beer so it was a lot of yeast..
 
My blichmann has a sightglass that has helped immensely and i watch it throughout the boil and do math in my head as to where I am in regards to how much ill lose in the hour boil. This last one was fairly consistent.

Another thing, the fermentation is very vigorous. Although thats probably becasue i pitched the yeast expecting a 1.080 gravity beer so it was a lot of yeast..

Did you insulate your sight glass? I have to stop the boil to get an accurate reading.
 
Did you insulate your sight glass? I have to stop the boil to get an accurate reading.

Blichmann gives you a piece of sheet metal to wedge under the pot to shield the sight glass and brewmometoer from excessive heat. Works great.
 
Blichmann gives you a piece of sheet metal to wedge under the pot to shield the sight glass and brewmometoer from excessive heat. Works great.

Hmm, I have a Blichmann kettle. My piece isn't really big enough to completely shield my thermometer and my site glass at the same time. I guess I'll have to experiment with positioning or something.
 
•
When batch sparging, the temperature of the mash-out and/or sparge water influence your extract efficiency. You want to make sure that either your mash-out infusion or your first batch sparge addition are hot enough to raise the grist to as close to 170 F as possible. This allows more sugar to be dissolved and reduces viscosity to facilitate easier lautering, both of which will improve your efficiency.

I hope you are still following this thread. I found it very helpful. I am a new brewer and breaking into all grain brewing. I keep missing my O.G. numbers (as suggested by the recipes) and am trying to figure out what I'm doing wrong.

My question about the statement above has to do with the 170F sparge temperature. I thought I underestood that at 165-170 we need to be concerned with tannin extraction. For that reason I've tried to hold my batch sparge in the mid 150's. Aren't tannins an issue here?
 
My question about the statement above has to do with the 170F sparge temperature. I thought I underestood that at 165-170 we need to be concerned with tannin extraction. For that reason I've tried to hold my batch sparge in the mid 150's. Aren't tannins an issue here?

Tannin extraction is most closely tied to high pH. As long as your pH is correct, you're good. Ever heard of a decoction mash? You boil the grain, which is certainly hotter than 170! It works because the pH is low enough to not extract undesirable tannins. I always use 185+ water for sparging. It helps complete the gelatinization and conversion of starches.
 
I always use 185+ water for sparging. It helps complete the gelatinization and conversion of starches.

Great info! Thanks! And yes I had heard of decoction and didn't put the pieces together in my mind. (duhh) I'll bet we are closing in on my low OG problem.

So what pH range is best?
 
OK, so here's the question ... I've got my mash perking along at 152 per the recipe - how do I determine the pH? Take a sample, let it cool then stick some litmus paper in it?

Also, what temperature is the grain during the sparge? Assuming we introduce 185F water into grain that is already at 145-150 from the mash, what temperature are we shooting for in the lauter tun during the sparge?
 
Also, what temperature is the grain during the sparge? Assuming we introduce 185F water into grain that is already at 145-150 from the mash, what temperature are we shooting for in the lauter tun during the sparge?

Temp doesn't matter at that point.
 
Temp doesn't matter at that point.

Wow! Now I'm really confused. Help me with this if you can. I've been given to understand that temperature is critical - too low and it doesn't convert the enymes in the grain -- too high and it leaches the tannins in the grain husks and releases puckery tannins into the wort. You are saying temperature doesn't matter? I'm trying to keep up with you and I am not doubting what you are saying, it's just that what you are saying seems to fly in the face of everything else I (think) I have learned to this point.
 
Wow! Now I'm really confused. Help me with this if you can. I've been given to understand that temperature is critical - too low and it doesn't convert the enymes in the grain -- too high and it leaches the tannins in the grain husks and releases puckery tannins into the wort. You are saying temperature doesn't matter? I'm trying to keep up with you and I am not doubting what you are saying, it's just that what you are saying seems to fly in the face of everything else I (think) I have learned to this point.

When you get to the sparge, conversion has already happened. And as Denny stated, it is pH, not temperature, that is most responsible for tannin extraction.
 
So if I understand you correctly, I can pour 160F sparge water into my mash tun or I can pour 185F water and, either way, so long as the pH is correct, the second runnings will rinse off the same amount of sugars from the grain?
 
So if I understand you correctly, I can pour 160F sparge water into my mash tun or I can pour 185F water and, either way, so long as the pH is correct, the second runnings will rinse off the same amount of sugars from the grain?

Not exactly. Hotter will typically result in more sugar dissolving. Solids dissolve more easily at hotter temperatures.

But sugar dissolving is different from conversion, which is what I was addressing in my previous post.
 
Ok, so forgive me for being a complete noob here, please. I thought conversion was the process of taking the stored (potential) sugars in the malt and releasing them into the mash or sparge water so it could be rinsed off and eventually become the stuff that feeds the yeast in the wort. The efficiency of the mash/sparge combination was simply a factor of the amount of potential sugars as opposed to the actual sugars released into the wort. Perhaps I don't have a clear understanding of what is actually taking place. Am I oversimpifying the process?
 
Ok, so forgive me for being a complete noob here, please. I thought conversion was the process of taking the stored (potential) sugars in the malt and releasing them into the mash or sparge water so it could be rinsed off and eventually become the stuff that feeds the yeast in the wort. The efficiency of the mash/sparge combination was simply a factor of the amount of potential sugars as opposed to the actual sugars released into the wort. Perhaps I don't have a clear understanding of what is actually taking place. Am I oversimpifying the process?

Conversion is when enzymes convert starches into sugars. Sparging is rinsing the grains. While some conversion may occur during the sparge, the conversion and the rinsing are fundamentally different things.
 
Conversion is when enzymes convert starches into sugars. Sparging is rinsing the grains. While some conversion may occur during the sparge, the conversion and the rinsing are fundamentally different things.

I think I got it. Thanks for your patience with me on this:

So conversion takes place during the mash, and only during the mash. The sparge is just to rinse off any remaining sugars in the grain that didn't run off with the mash. Right?

If the sparge pH is critical I think I'd better learn the best way to test it. What do you do?

But doesn't the temperature of the sparge matter at all?

"""
 
Sparge temps matter because they will determine how much sugar will be solved in that sprage cycle.
Think about it this way. When you drink coffee and you put sugar in it, desolves quickly doesnt it? Ever tried iced coffee and sugar? Doesnt work well. Same principle for beer.
Once the sugars have been released during the mash there is no need to worry about much other then making sure you have some hot water. I perfer 170-175. Some people may do it differently. I think tannins are more of a worry when you are mashing. Keep those mash temps under 170 (imo)
PH is important for mashing because it creates an ideal environment for the grain to think it is sprouting. That in return releases its glorious reward.

Any who, Cheers.
 
I think I got it. Thanks for your patience with me on this:

So conversion takes place during the mash, and only during the mash. The sparge is just to rinse off any remaining sugars in the grain that didn't run off with the mash. Right?

Pretty much. You may have a very small amount of additioanal conversion going on during the sparge, but the vast majority will occur during your mash, assuming you mashed properly. :D

If the sparge pH is critical I think I'd better learn the best way to test it. What do you do?

For me, the easiest way to ensure I don't have issues with sparge pH is to acidify my sparge water to around 5.5 pH. If you're using distilled, RO, or otherwise low alkalinity water, that's probably not even necessary, as the buffering capacity of the mash will keep the pH down. If, however, you're sparging with higher alkalinity water (as many municipal waters are), then you do run the risk of higher pH occuring. I use phosphoric acid.

But doesn't the temperature of the sparge matter at all?

Well, you don't want to sparge at say, 100 degrees, as the sugars won't be as soluble. I think most people sparge with water in the 170-180 range.
 
Sparge temps matter because they will determine how much sugar will be solved in that sprage cycle.
Think about it this way. When you drink coffee and you put sugar in it, desolves quickly doesnt it? Ever tried iced coffee and sugar? Doesnt work well. Same principle for beer.

There's no sugar in solid form to be dissolved. Your mash starts out with solid starches, which are drawn into solution as part of enzyme conversion. At no point do you have actual crystals of sugar waiting to be picked up by the water.

Furthermore, the solubility of sugar in even 150ºF water is well above anything that would be a limit for brewers. I'm going off of memory here, but I believe the number is somewhere around 1.400.

Some people do notice increased efficiency from a warm sparge, but I never have. I've sparged with both hot and cold water over dozens of batches, and my efficiency is incredibly consistent. I suspect those who are getting better efficiency from a mash out are either (a) ending the mash a bit early, and the mash out speeds up the last remaining conversion or (b) having grain bed fluidity problems and are thus getting a more complete lauter from warm temperature.
 
Furthermore, the solubility of sugar in even 150ºF water is well above anything that would be a limit for brewers. I'm going off of memory here, but I believe the number is somewhere around 1.400.

Yes, but if you get really technical about it, even if you're not at the solubility limit, i think the sugars will have a stronger driving force to migrate from the grains to the bulk liquid at higher temps. At least that's what I think I remember from p-chem. :p

Now, whether that change in driving force is actually relevant in a typical homebrew situation..... totally different question, and one to which I must admit I have no answer.
 
Yes, but if you get really technical about it, even if you're not at the solubility limit, i think the sugars will have a stronger driving force to migrate from the grains to the bulk liquid at higher temps. At least that's what I think I remember from p-chem. :p

Now, whether that change in driving force is actually relevant in a typical homebrew situation..... totally different question, and one to which I must admit I have no answer.

Certainly, but remember, there's never a point where you have solid crystal sugar waiting to be snatched up by the water. It's not as though the solid grain with solid starches turning into solid sugars, which then get dissolved. The entire enzymatic process of the mash happens already in solution.

If you've got remaining solids at the end of the mash, they're not sugars but starches. If you've got significant remaining starches, relative increases in solubility won't help you.

At least, that's my understanding. :)
 
Back
Top