Maximizing Efficiency when Batch Sparging

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tochsner said:
This is my story as well. I done a bunch of BIAB and had it dialed in pretty well around 72-75%
Today I did my first mash in a cooler following the steps outlined here and ended up around 54.8%. I have my own mill and have been doing well with the crush that I have it at. Today's recipe was 60% wheat malt. Do I have to crush finer with wheat? I know the kernels are a little smaller.

I've done a few other batches since my last post. I think my problem was not preheating the mash tun also not considering heat absorption from the cooler.
 
Tizzomes said:
I've done a few other batches since my last post. I think my problem was not preheating the mash tun also not considering heat absorption from the cooler.

One more think to answer your wheat question I've brewed two consecutive strawberry wheat beers.I also have a grain mill ( Barley Crusher from Northern Brewer ) I left the gap setting alone but used a half pound if rice hulls.I guess you could have a finer crush I would just use more rice hulls to prevent a stuck sparge.
 
I've done a few other batches since my last post. I think my problem was not preheating the mash tun also not considering heat absorption from the cooler.

I didn't read the entire thread, so I don't know if you mentioned this before, but do you use software like BeerSmith? I use BS and can tell you it takes into consideration the thermal mass (which goes to heat absorption) and other physical aspects of the mash tun. And it compensates for them.

In my, probably limited, experience with the software, it doesn't give me anything totally exact, but the numbers are lot more accurate than winging it and as I hone other techniques, such as making sure I stir the mash well and for a good amount of time, my numbers get closer and closer to those of the software.
 
My efficiency sucks. Worse than that, it's not even reliably sucky. Sometimes 60%. Sometimes 65%. Sometimes under 60%. I'm not greedy. I just want a nice, healthy 70%, give or take a couple %'s. I understand that bigger beers will suffer in terms of efficiency. I'm not talking about huge beers. I'm talking about regular sized beers. OGs of 1.045 to 1.060. Next beer I'm doing is going to be a Kolsch. I Will collect 7.7 gallons preboil, and will boil for 90 min down to a 6 gallon post-boil batch. I'm using Chicago, Lake Michigan water, untreated.

My water:

Calcium - 35 ppm
Chloride - 13 ppm
Alkalinity (CaCO3) - 105 ppm
Magnesium - 11 ppm
Sodium - 10 ppm
Sulfate - 10-25 ppm

My grain bill:

10 lbs pils
8 oz munich
8 oz wheat
4 oz carafoam (carapils)

Here's what I'm going to do about my efficiency:

I'm going to preheat my Coleman Xtreme cooler mash tun with water ~15F hotter than my strike temp. I will preheat for at least 20 minutes. Then I will stir the water down until it reaches strike temp.

I will use Beersmith to give me an accurate strike temp. (On this matter, I've never been let down. I nail it within a degree everytime.)

I will use Beersmith to calculate my efficiency into the kettle.

I'm going to dough-in at a moderate pace, pouring my grains into my very preheated mash tun, stirring all along the way, being VERY careful to break up any doughballs. I will continue to stir the mash, with my mash paddle, after doughing in, for another 3-4 minutes.

I'm going to calibrate my dial thermometer at boiling point, accounting for local atmospheric pressure, so I can better trust it when it says 154F, or whatever.

I'm going to give the mash a stir once or twice throughout the 60 minute mash.

I'm going to keep my preheated mash tun inside and cover it with blankets to better hold mash temp over the course.

I'm going to use Iodophor to ensure a non-positive starch result after the 60 minute mash.

[I am NOT going to measure the pH of my mash. Not without a good pH meter. Something I don't have.]

I'm going to mash at a water/grain ratio that will give me at least a gallon of top-off water, which I will bring to boiling before adding back to the mash for the 1st run-off.

I'm going to heat my sparge water to raise the mash to 165-170 before the 2nd run-off.

Both of my run-offs start out slowly for about 20 seconds, then I open 'er up and let 'er rip.

I'm going to, once again, calibrate my measuring rod which I use to measure the volume of pre-boil wort I collect. I will know how many gallons I have collected to the nearest tenth of a gallon.

***************

If I do all of this, and my efficiency is still under 65%, what next? The only unknown I'm leaving behind is pH and my crush. Can I automatically blame the crush? Is pH a possibility? But what if people using my same water and the same mill from the same HBS are getting much better efficiency? Where could I possibily be failing myself?

Long post. Sorry.
 
Here's what I'm going to do about my efficiency:

I'm going to preheat my Coleman Xtreme cooler mash tun with water ~15F hotter than my strike temp. I will preheat for at least 20 minutes. Then I will stir the water down until it reaches strike temp.

I will use Beersmith to give me an accurate strike temp. (On this matter, I've never been let down. I nail it within a degree everytime.)

Keep in mind that if you pre-heat your mash tun you need to let BeerSmith know, otherwise it will still assume a bunch of heat will be lost to a cold mash tun and you'll end up really high for your strike. This can be done by unchecking the "Adjust temp for equipment" box. (see this link)

Pre-heating and stirring down to strike temp is lost time for a critical path task so I try to reduce it as much as possible since it directly affects your overall brew day length. Miscalculating that strike temp way too high makes that day even longer and is pretty frustrating. Ask me how I know. :)
 
Keep in mind that if you pre-heat your mash tun you need to let BeerSmith know, otherwise it will still assume a bunch of heat will be lost to a cold mash tun and you'll end up really high for your strike. This can be done by unchecking the "Adjust temp for equipment" box.
I tell Beersmith my mash tun is roughly the same temp as my target stike temp. Usually 165F or so. I assume this leads Beersmith to assume no heat loss.

Like I said, I never have any troubles [according to my thermometer] hitting my target mash temps. Whether my thermometer is accurate is another matter, but one which I also plan to address.

It's efficiency, either in conversion, or in lautering, or in grist potential, or a combination of some or all, that I'm struggling with.
 
ASantiago said:
I didn't read the entire thread, so I don't know if you mentioned this before, but do you use software like BeerSmith? I use BS and can tell you it takes into consideration the thermal mass (which goes to heat absorption) and other physical aspects of the mash tun. And it compensates for them.

In my, probably limited, experience with the software, it doesn't give me anything totally exact, but the numbers are lot more accurate than winging it and as I hone other techniques, such as making sure I stir the mash well and for a good amount of time, my numbers get closer and closer to those of the software.

To answer your question no I don't use any brewing software.I probably should it's cheap enough huh...
For a regular 10 to 12 pound mash I use 3 1/2 gallons of strike water and mash in at about 170 to 180 degrees. I would rather be a bit high and stir for 10min to reach my desired mash temp.With 2 kids under 2yrs old and the fact I brew when there asleep I'm not to technical.
 
This thread's been a great read. One question I had was, why should we aim to have the first runnings make up approximately half of the pre-boil volume? Just curious as to why this helps with efficiency. Cheers!
 
axeman9182 - the reason to aim for 1/2 of the boil volume as your sparge volume is that volume provides plenty of water to wash the sugars out of the mash. If the sparge volume gets to be too small a percentage, you leave sugars behind in the mash. The first page of this thread has some comments by Kaiser with links to a lot of detail on the impact of the sparge volume percentage to efficiency.
 
I have not quite figured out how to use my dead space under the false bottom. I have a 40 gallon Stout Mash tun that holds 2.5 gallons under the false bottom. I do HERMS and normally add 1.25 qts per pound on top of the 2.5 gallons. I do use batch sparging and always adjust my volume to hit my OG ( Normally by adding boiling water at 15 minutes along with Irish Moss and Nutrient but sometimes have a boil off (normally we always start where we will have to add water so only once have I had not to add water). Do I count the 2.5 gal in the 1.25 qts per pound (I have not)? Also things seem to work better with a wetter mash.
 
I have not quite figured out how to use my dead space under the false bottom. I have a 40 gallon Stout Mash tun that holds 2.5 gallons under the false bottom. I do HERMS and normally add 1.25 qts per pound on top of the 2.5 gallons. I do use batch sparging and always adjust my volume to hit my OG ( Normally by adding boiling water at 15 minutes along with Irish Moss and Nutrient but sometimes have a boil off (normally we always start where we will have to add water so only once have I had not to add water). Do I count the 2.5 gal in the 1.25 qts per pound (I have not)? Also things seem to work better with a wetter mash.

I was wondering the same thing. I did my first all grain last weekend and I got about 7 gallons out of my mash tun after draining the mash. I was going to sparge twice with 3 gallons each to put me at 13 gallons preboil. I added the three gallons and there wasn't enough liquid to submerge the grain bed, so I added the remaining three gallons, but I don't think I stirred enough. I didn't think I needed to stir if I was running it through the HERMS coil and recirculating though.
 
axeman9182 - the reason to aim for 1/2 of the boil volume as your sparge volume is that volume provides plenty of water to wash the sugars out of the mash. If the sparge volume gets to be too small a percentage, you leave sugars behind in the mash. The first page of this thread has some comments by Kaiser with links to a lot of detail on the impact of the sparge volume percentage to efficiency.

Thanks, that makes sense. So if your first runnings are going to provide less than half your preboil volume you can just mash thinner, I take it if they're going to provide more than half your volume you should just boil longer and sparge more?
 
If I recall Kaiser's information, the sparge efficiency is pretty good (similar) over a range that might be from 40 to 60% (guessing) of preboil volume. At some point it starts to see significant impact. I wouldn't get real specific about hitting 50% but you want to be somewhere around there.

Your suggestions on how to get closer to 50% are correct although remember that changing the mash thickness and/or boiling longer can have other impacts. Whether that matters depends of the specific beer you are making.

Another variable is the temp of the water for the infusion. At times I have raised the infusion temps - to reduce the water volume - which allows for larger sparge volumes. There are a lot of ways to mash, which can provide a lot of variation in the first runnings/sparge ratio.
 
I'm struggling to reconcile mash density and efficiency. Denny, in a recent post, you suggested a mash density of 1.66 to 2 qt/lb to improve fluidity. First of all, I assume that this density represents the strike and the sparge volumes separately.

I'm trying to hit 75% efficiency, at least. If I want a 6.5-gal post-boil wort at OG=62, I start with a 14.5# grain bill. To produce 7.75 pre-boil wort, the initial strike calculates at 15.5 qt., plus an additional infusion of 7 qt. toward the end of the mash to make up for absorption (.125 qt/lb for my system). The sparge would also be 15.5 qt. So, there's no way I'm getting a mash density much higher than 1.07.

Do I have to resign to low efficiencies for higher gravity worts? I understand there are other issues related to boiling higher volumes longer to achieve a target gravity, so I'm not inclined to go that way.
 
I'm struggling to reconcile mash density and efficiency. Denny, in a recent post, you suggested a mash density of 1.66 to 2 qt/lb to improve fluidity. First of all, I assume that this density represents the strike and the sparge volumes separately.

I'm trying to hit 75% efficiency, at least. If I want a 6.5-gal post-boil wort at OG=62, I start with a 14.5# grain bill. To produce 7.75 pre-boil wort, the initial strike calculates at 15.5 qt., plus an additional infusion of 7 qt. toward the end of the mash to make up for absorption (.125 qt/lb for my system). The sparge would also be 15.5 qt. So, there's no way I'm getting a mash density much higher than 1.07.

Do I have to resign to low efficiencies for higher gravity worts? I understand there are other issues related to boiling higher volumes longer to achieve a target gravity, so I'm not inclined to go that way.

OK, let's see if I understand what you're getting at.....first, if you haven't worked on your crush, that's the place to start. If you have a poor crush, no other measures will really make a difference. I've started using enough mash water that I don't need to do what you call the "make up for absorption" addition (it's not really that, anyway). Then I simply sparge with enough water to get my total boil volume. Higher gravity worts will pretty much always reduce your efficiency, but mine stays in the mid 80s up to a mid 80s OG. I started by working on my crush. That gained me quite a bit. By fine tuning my water chemistry and amounts I've managed to add the rest of my efficiency increase.
 
OK, so here’s where I am after the June 12 post and reply.

I usually buy the pre-crushed 2-row malt at my LHBS, and it appears to be very fine, then I grind the specialty malts, which comprise about 25% of my grain bill, using their mill. For my next session I noticed that it was still quite coarse after milling so I asked the owner about it and he said that he sets the gap just wide enough to crack the grain, but not too fine to cause a stuck sparge. So then I did something pretty unconventional: I threw the under-milled grain into my Cuisinart at home one small batch at a time and whirred it around until it started looking like the pre-milled malt. Because I’m using a hose braid, I wasn’t particularly worried about a stuck sparge.

Then I mashed using more strike water than usual to increase fluidity, and stirred vigorously after infusion and again after adding the sparge. This time, however, I added quite a bit more sparge water than I needed (after reading several suggestions in this string), and stopped the flow when I hit my preboil volume. No problem with sparge flow, as expected. I took an end-of-running gravity for the first time, and it seemed pretty high at 30; then after mixing the wort thoroughly, I took a total pre-boil gravity reading, and it was still lower than I was looking for at 45. Post-boil OG came in at 55, several points lower than my target of 62, which is what it calculates at 75%, assuming I’ve done everything right.

So still confused, but not discouraged. All of the beer I’ve made so far has been delicious. It’s just frustrating not to be able to predict and achieve the results I want. I just went back to an earlier post and found a link to Ken Schwartz’ article on how to sparge, and I think I’m beginning to understand the water volumes a bit better. I’m going to go back to just adding enough strike water for a “normal" mash then add a little more before vorlauf to increase fluidity, then sparge with just the 50% balance and see what happens.

Make sense?
 
It does make sense. What you found when you over-sparged (and your end-running gravity was 30), was that you still had a lot of sugar left in the mash tun by the time you achieved your pre-boil volume. That obviously hurt your efficiency. Ideally you want to run all the fluid out of the tun exactly as you hit your pre-boil volume.
 
The saga continues with mash efficiency and gravity dilemmas.

I've been working on improving my batch sparge techniques (getting better!), but I'm ending up with irreconcilable gravity readings. Yesterday, I mashed 14.5 lbs of grain crushed at .024", and produced 7.75 gal of wort with a pre-boil gravity of 1.050. Since I was shooting for an OG of 1.062, I calculated the final boil volume before cooling at 6.5 gal, figuring I'd lose another .25 gal when cooled (based on the formula: 7.75 gal x 50 = 387.5 pts; divided by 62 = 6.25 gal cooled). What I actually got after boiling and cooling was 1.058. If you're wondering, I adjusted all gravity readings to 68 F, so that's not the problem.

If the sugar content in the wort is constant, and the density is a function of wort volume, is there something wrong with my math, or are my water or hydrometer calibrations out of whack?
 
I've recalibrated once already, but I don't mind doing it again. I think I'll take my hydrometer into my LHBS next time and see if it matches theirs. They make a lot of good beer on site.

Do I have the "conservation of sugar" formula right?
 
It checks out in water.

But are my calculations solid? If I start at 1.050 and 7.75 gal preboil (387.5 pts) shouldn't I end up at 1.062 and 6.25 gal post-boil? I want to confirm the math while I look at calibrations.
 
Viejo said:
It checks out in water.

But are my calculations solid? If I start at 1.050 and 7.75 gal preboil (387.5 pts) shouldn't I end up at 1.062 and 6.25 gal post-boil? I want to confirm the math while I look at calibrations.

The math is correct, though it's a small enough margin of error that it is easily attributable to measurement errors. That's why people are keying in on that.
 
If the sugar content in the wort is constant, and the density is a function of wort volume, is there something wrong with my math, or are my water or hydrometer calibrations out of whack?

Another possibility, did you stir the wort thoroughly before taking your sample? If not that could explain why the sample read lower than expected.
 
Yeah, pretty well. The final runnings read 1.025, and the preboil gravity was 1.050, so I think it was stirred pretty well.
 
I've been trying to fix my efficiency problems for a while now. I normally get 60-65% with grain milled at my LHBS. This time, I took those milled grains and used a friend's mill set fairly small (don't know the gap size). Here's the grain bill I used for this recent recipe...

Code:
11 lbs 	Pale Malt (2 Row) US
2 lbs 	Munich Malt
1 lbs 	Caramel/Crystal Malt - 40L
8.0 oz 	Chocolate Malt
6.0 oz 	Acid Malt
4.0 oz 	Midnight Wheat

I mashed with 5.75 gal of water at 164.9 F (153F mash temp) and sparged with 4.15gal of 180.0 F water.

1st runnings: 4gal, 1.074
2nd runnings: 4gal, 1.032
Pre-boil: 8gal, 1.054

Using Kaiser's efficiency brewsheets, I noticed that on this batch I got 91.6% conversion effiency (way higher than usual).

After everything was finished, I added 5 gal cold water to the mash tun, stirred and drained. From that, I got 1.020 wort. The spreadsheet says this is a 68% lauter efficiency.

Is that a normal lauter efficiency for batch sparging with a 10gal Igloo cooler?
 
• Your crush will have a big impact on your mash efficiency (although some debate this point). Regardless, the biggest gains in efficiency that users tend to report are when they improve their crush (e.g., buy their own mill). If your LHBS is crushing your grain for you, consider that most shops will set their crush so that their customers get between 60 and 70% efficiency. They may claim it is to help brewers avoid stuck mashes, but conveniently, it also helps them to sell more grain!

I think I just had this issue. I just switched to a new LHBS for my last two brews and both batches we hit an OG that was significantly below the target OG.
For the first, I wrote it off as my new digital thermometer being off, but when I verified everything was correct for the second and the numbers were still .03 off, I had to assume it was the crush.

Perhaps its time to get my own....
 
Hey gang,

Just finished my first IPA today, really stoked to try this one out.

My Measured Mash Eff was 74.3
My Measured Eff was 63.8

Recipe
11.0 lbs of Maris Otter
2.0 lbs of Vienna Malt
1/2 lb Para-Pils
1/2 lb Caramel Crystal 20L
1.25 Qts per lb for mash mashed at 153* for 65 mins
Batch sparged with 4.0 gal in two batches, 170*
My final runnings was 1.032 at just shy of 7.0 gal in an 8 gal pot. This seems very high to me. What should I be looking at to get closer to 1.010 at 7 gal?

My digital thermometer is accurate, stirred like mad for each sparge... The crush was done by my LHBS and I always ask them to tighten it up from standard which they do, it was set to .20 on the gauge FWIW

Where do I go from here?
Thanks in advance
Toy4Rick
 
Sounds an awful lot like my IPA grain bill. What was your preboil gravity and your OG? What was your postboil volume? My end of running gravities are typically pretty high too, like .030, and I've wondered if I can do any better batch sparging.
 
Measured pre-boil was 1.058
OG was 1.064
Post boil volume was 5.5 gal

All my numbers seem pretty spot on except for end of runnings gravity

Toy4Rick
 
Toy4Rick said:
Measured pre-boil was 1.058
OG was 1.064
Post boil volume was 5.5 gal

All my numbers seem pretty spot on except for end of runnings gravity

Toy4Rick

I think there might be some confusion here. Where are you getting the idea that you're looking for 1.010?

"End runnings" is usually a term associated with fly sparging. In batch sparging, I'd expect my second drain to produce something like what you got in the 1.030s range.
 
We batch sparge and have added 1/2 pound of 2 row per 5 gallons for lost %. We used to sparge until we got to 1.018 or so. We now just sparge on volume and no longer worry about the ending sg. We adjust the volume for our final gravity. I try to shoot where I will not have to excessively boil off or add water. We are not a "big brewery" where we care about $$ as much as time. We err on the extra grain (and some extra Wort) normally but we get our brew day done in six hours(All clean and put away).
 
So where did I get 1.010...

Well, it's the default in BeerSmith and I have read it here on this forum more than once.

It seems to me at 1.032, there is still quite a bit of sugars still in the grain, leading me to believe my effeciency is still pretty low.

If you are saying this is what should be expected with batch sparging, then so be it

Toy4Rick
 
I'm going to be brewing my Oatmeal Milk Stout next week and have been having problems with efficiency. I've been hitting 70%-75% but I'm looking for more consistency. I've read a lot of this thread and have decided to do a second sparge. One thing that confused me though is that Hopville recommends doing the first sparge with just .3 gallons of water, then 2.8 gallons for the second. Is this normal or should I just measure out 3.1 gallons and split it between the two sparges?
 
So where did I get 1.010...

Well, it's the default in BeerSmith and I have read it here on this forum more than once.

It seems to me at 1.032, there is still quite a bit of sugars still in the grain, leading me to believe my effeciency is still pretty low.

If you are saying this is what should be expected with batch sparging, then so be it

Toy4Rick

Yeah, that's not out of the ordilnary for batch sparging. Keep in mind that the 1.010 number for fly spargingis not a hard limit, but rather a way to tell that you might not have enough buffering capability left in the grain to prevent the pH from rising. pH is the real issue and the 1.010 number is just an easy way to be aware of that.
 
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