# Efficiency still in the crapper



## mr_wibble (23/9/13)

G'day,

Here's the on-going saga with my efficiency ~

I talked to the LHBS dude, and he advocated stirring the mash to help improve my efficiency.

So on the last brew, here's how it went:

Buy roughly 6kg of grain (60% pilsener, 40% wheat), for a 23 litres brew at 65% efficiency


Pre-warm mash tun a bit (it was 6 degrees outside, as I started at 05:30)
Add Grain
Add 15 litres of water at 76C to hit step temperature of 67C
Stir vigourously
Wait 15 minutes
 Stir Vigourously
(repeat 3 times)
Draw off wort
Add 21 litres of water at 76C
stir vigorously
Draw off 2nd-runnings

I estimate I had about 27 litres in the kettle

Boil vigorously for 1 hour (add hops etc.)

So ... I boiled too vigorously again ... ended up with 18 litres in the fermenter.

But since I boiled off so much I actually hit the desired specific gravity - 1.052 (that's 0.002 over).

So even with the efficiency bar set so low, I still only achieved about 78% of that... what does that make the final efficiency ... about 50% right? *sigh*

Attached is some photos of my esky-tun, obviously it has a lid too.

I tasted some grain after sparging, it was still very sweet.

Maybe I should double-sparge or something ?

Any ideas?

thanks,
-kt


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## vortex (23/9/13)

What's your crush size/mill gap? How long are you taking for your sparge? Sparging too fast will leave sugar behind


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## MikeHell (23/9/13)

Have you rated the extract/yeild percentage of the grain accurately in your recipe software/calculator?

Personally I do equal mash and sparge water (generally 3L water to 1kg grain), so for you would be 18L mash & 18L sparge, might be worth a go.


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## manticle (23/9/13)

Before you start looking at ways to improve, find out which part of the process needs improvement. Are you not achieving proper conversion?

Measure first runnings gravity and get a sense then if that's where the problem is, look at strike temps, grain crush, measuring equipment, mash pH etc.
Are you not extracting enough sugar from your sparge? Look at manifold design and placement, sparge temperatures, sparging technique etc.
Find out where and what the problem is before throwing every tool at it trying to fix it.

In my experience you shouldn't need to stir that much to fix efficiency issues. You'll just lose temperature.
Meanwhile set your efficiency to where it actually is, rather than where you want it to be and adjust recipe accordingly till you work it out (obviously set it where you want it when running your tests to see where and how far off you are).


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## Thefatdoghead (23/9/13)

Is your thermometer correct or have you checked with a glass type thermometer? Also is the wheat malted or raw or what? As Manticle said, check your PH as this may be out as well.


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## verysupple (23/9/13)

What others have said is of course correct, I just want to add my experience.

I've only done 14 brews with grain (partials and AG) and when I started I would get ~65% eff. into the kettle and it slowly rose to ~75% as I improved. Then I did a couple of batches with large portions of wheat malt (>50%) and my efficiency took a big hit and dropped to ~50%. I looked at things like pH and water chem, but couldn't adjust the crush as many said to do with wheat becuase I buy my grain already crushed from the HBS.

To make a long story short, I figured out I wasn't getting very good conversion with the wheat and I just needed to mash longer. When I went from 60 min to 90 min mashes my wheats got up to my normal efficiency. This might work for you, but as Manticle said, you should figure out where your problem is, i.e. conversion, lautering etc.

Since then I've increased my usual efficiency into the kettle to 80 - 85% by doing a mash out. The higher temp (lower viscosity) lets me get a lot more liquid (and therefore sugars) out of the grain (I do maxiBIAB).

So now I'm happy with both my conversion eff. and my "lautering" eff.

EDIT clarification


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## MikeHell (23/9/13)

Similar experience as above, with addition of only 12% wheat malt, brought usual 75-80% efficiency down to 65% using the same routine as usual.


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## pyrosx (23/9/13)

Temperature - you've listed a whole bunch of steps, and only mentioned temperature twice - 76C for water out of a HLT.

If the thermometer in your HLT is even a couple of degree's off, and you're not measuring anywhere else.... then everything beyond that is going to be out of whack.


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## mr_wibble (23/9/13)

vortex said:


> What's your crush size/mill gap? How long are you taking for your sparge? Sparging too fast will leave sugar behind



Grain crush size is whatever the LHBS sets it to.

I guess my sparge takes about 15 minutes to run off, but I haven't timed it.


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## mr_wibble (23/9/13)

Thanks for all the info ... I'll have to cogitate on all the ideas and suggestions a bit.

I don't take mash temperature measurements, I take it on faith that adding X degrees of water gives me the target temperature. Which on the face of it does sound a bit naive.


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## manticle (23/9/13)

Iron out all the possibilities.

Definitely measure your mash temp accurately.

Every time.


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## pyrosx (23/9/13)

http://www.wiltronics.com.au/catalogue/180803/science/thermometers

The sub-$10 one on the bottom of that list... buy 2. 

Test both in heavily iced water, then in kettle-still-on-boiling water... the one that reads closest to 0 and 100 is your brewery thermometer. The other one that is only a degree or so off is great for the kitchen.


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## pyrosx (23/9/13)

I'm completely serious about having a second digital thermometer for the kitchen too... if you're into beer enough to be attempting AG homebrew, i'd be stunned if you didn't have an interest in cooking decent food as well. I'd probably let someone take away my knives before letting them have my thermometer.... The difference between chicken at 65 and 75 is only about 5 or 10 minutes in the oven/bbq, but the difference in taste and therefore enjoyment is ridiculous - and there isn't another tool, method or trick in the world that will tell you properly when that chicken is done. And don't get me started on deep frying oil temperature....


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## slcmorro (23/9/13)

pyrosx said:


> The difference between chicken at 65 and 75 is only about 5 or 10 minutes in the oven/bbq, but the difference in taste and therefore enjoyment is ridiculous


And not throwing it up the next day


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## vittorio (24/9/13)

i normally batch sparge because its much quicker but the efficiency is always low.... so i found a way around that, add 10-15% more base malt to the brew when batch sparging and it will equal to the right efficiency amount!


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## jimmy01 (24/9/13)

I have had similar problems when there is a high % of wheat in the grain bill. Have found running the wheat malt and raw wheat through the mill twice helps to improve efficiency


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## BeerNess (24/9/13)

Mr Wibble said:


> Grain crush size is whatever the LHBS sets it to.
> 
> I guess my sparge takes about 15 minutes to run off, but I haven't timed it.


Grain crush - Specify with your LHBS!!! Otherwise you can get into all sh!t if they just throw it through at whatever it was last set to, massive efficiency changes possible there. 

Sparge - I'm a BIABer so not an authority but are you letting your batch sparge rest for 30 min or so before running it off?

Smarter people than I have already highlighted wheat being better in a longer mash. 

Record your 1st and 2nd runnings gravity, get some iodine to check your conversion. 

Sounds like even for a 60min boil you need to increase your mash/sparge volumes to compensated for your evaporation rate. 

Something I've learnt recently that's helped me with some brewhouse problems is MEASURE AND RECORD EVERYTHING for every brew. 

Good luck!!!


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## pimpsqueak (24/9/13)

So are you actually doing a mash-out?
If you stirred 3 times and it was that cold outside, you must have lost a few deg.
Then you added 21L @ 76 deg which given the volume already in your tun, wouldn't have hit 75-78 deg. 
These temps reduce the viscosity of your mash and make it easier to extract a higher percentage of sugars.
Next time, do a 90 min mash, perform a starch iodine test for full conversion and then give it a 10 min rest at mash out temp before running off and sparging.

My 2c.


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## yum beer (24/9/13)

I agree with the idea of upping your grain bill amount.
I feel a lot of brewers get caught up too much with hitting certain eff. numbers. Yes it would be great to hit 80% every brew but the reality is we are all using different equipment to make our beer.
Keep records and work towards getting consistent figures from your brew day.
I use BIAB with a seperate dunk sparge and hit around 61-63% eff. into the fermenter....not great but thats what my sytem gives me and it works nicely for me, I need an extra .5 - 1kg of grain to get my volumes than I would if hitting 70% or better, but at under $3 extra for each batch I don't care.
I'm half way through fitting out my esky mash-tun and no doubt will have to start again regards hitting the numbers I want.
The most important thing is getting your volumes into the fermenter right; at the SG your after.


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## verysupple (24/9/13)

yum beer said:


> I agree with the idea of upping your grain bill amount.
> I feel a lot of brewers get caught up too much with hitting certain eff. numbers. Yes it would be great to hit 80% every brew but the reality is we are all using different equipment to make our beer.


Some of us need to keep the efficiency up because we can't mash any more grain  . I use a BigW 19 L pot and with 4.5 kg of grain and a liquor-to-grist ratio of 2.67 :1 (L/kg) it's full to the brim. 





BeerNess said:


> Sparge - I'm a BIABer so not an authority but are you letting your batch sparge rest for 30 min or so before running it off?


I'm not an authority either, but I've found that if you get all the conversion done in the mash you don't need to let it sit, just give it a really good mix to get the sugar into the water and it's all good. If you get poor conversion during the mash and then let it sit for 30 min at ~76 C isn't that going to make a rather dextrinous beer? I know a-amylase will probably denature at that temp but it's going to take a fair while, and before it does it's going to go nuts on the starches, but b-amylase will have denatured and you're left with dextrins etc. Although I could be wrong.


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## QldKev (24/9/13)

Take a pic of the crush and put it up.


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## wbosher (24/9/13)

90 minute mash for me, I got an extra 5 points or so just by doing that. It's an extra 30 minutes to relax and have a home brew.


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## slcmorro (24/9/13)

With an extended mash, are you blokes upping the temp a little to compensate? Say at 67c mash temp for 60 mins, bumped to 69c mash temp to counter the difference? Or just not worrying?


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## .DJ. (24/9/13)

i mash for 90-120 or even 3 or 5 hours and dont compensate....you dont loose much temp over that time...

Most of the conversion is done early from what I understand so i dont think it would matter???


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## DJ_L3ThAL (24/9/13)

wbosher said:


> 90 minute mash for me, I got an extra 5 points or so just by doing that. It's an extra 30 minutes to relax and have a home brew.


So typical recipes (let's say Dr. Smuto's GA) that call for a 60min mash, if doing a stovetop going for a high gravity to be diluted in the FV, would a 90min mash get more gravity points then the recipe 60?



slcmorro said:


> With an extended mash, are you blokes upping the temp a little to compensate? Say at 67c mash temp for 60 mins, bumped to 69c mash temp to counter the difference? Or just not worrying?


My understanding is that your strike temp/mash temp is more important than holding your mash if we are talking a few degrees loss over 60-90min, the effect of upping the temp to compensate could result in unintended results, can someone confirm?


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## wbosher (24/9/13)

DJ_L3ThAL said:


> So typical recipes (let's say Dr. Smuto's GA) that call for a 60min mash, if doing a stovetop going for a high gravity to be diluted in the FV, would a 90min mash get more gravity points then the recipe 60?


I've only ever done full volume, so can't really answer that. But in my limited experience, I have noticed a difference with the extra 30 minutes...and that does include the good doctor's recipes. It's only an extra 30 minutes, can't hurt to try.


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## DJ_L3ThAL (24/9/13)

wbosher said:


> I've only ever done full volume, so can't really answer that. But in my limited experience, I have noticed a difference with the extra 30 minutes...and that does include the good doctor's recipes. It's only an extra 30 minutes, can't hurt to try.


Cool will experiment on my stovetop rig setup, did a 90min mash for my first brew and 60min for second but were different recipe, will try a 90min mash and do a 2nd Smurto's GA in anticipation that is is going to taste absolutely gorgeous in 3.5 weeks when it's in my mouth.


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## verysupple (24/9/13)

slcmorro said:


> With an extended mash, are you blokes upping the temp a little to compensate? Say at 67c mash temp for 60 mins, bumped to 69c mash temp to counter the difference? Or just not worrying?


Yeah, the longer mash seems to result in a _slightly _more fermentable wort as the literature suggests. I only end up about 1 - 2 points lower, though, so only needed to bump my mash temp up about 1 C. You could probably just leave it and not notice the difference when you taste it (although it's hard to judge when you _know_ the FG was lower than last time and expectations sway you).

EDIT: To clarify, it's not the drop in temp that leads to the higher fermentability, it's the fact that b-amylase has more time to chop down the longer chain sugars (that a-amylase has already converted from starches) into short ones.


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## verysupple (24/9/13)

DJ_L3ThAL said:


> So typical recipes (let's say Dr. Smuto's GA) that call for a 60min mash, if doing a stovetop going for a high gravity to be diluted in the FV, would a 90min mash get more gravity points then the recipe 60?


It depends... If you get complete conversion in 60 min then another 30 min will not yield anything more in terms of specific gravity (it might have a small affect on the fermentability, though (see above)). If you don't get complete conversion in 60 min then the extra time should help.


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## Phillo (24/9/13)

I tried a 60 min mash once with no other variables, and went from 70s down to late 60s. I do 90 min now.

I reckon crush size and temperature of your sparge also make a difference. I do a two stage batch sparge and get ~75% efficiency.


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## malt_shovel (24/9/13)

Mr Wibble said:


> I tasted some grain after sparging, it was still very sweet.
> 
> Maybe I should double-sparge or something ?
> 
> ...


If the grain is still very sweet, then it sounds like you are getting conversion, you are just leaving it behind.

If you are not measuring anything, it is impossible to say, but best guess is that you are channelling from draining too fast, leaving sweet wort behind.

In an ideal world, you would measure volumes added and grain added accurately. Compare the gravity of the first runnings to this table based on the grist / liquor ratio (http://braukaiser.com/wiki/index.php?title=File:First_wort_gravity.gif). If you are not close to this number, look at crush, mash pH etc and cosider mashing for longer or a profile to improve conversion (acid rest for this grain bill may help). Check out braukaisers notes on understanding efficiency from the link above.

Also measure second runnings if batch sparging to see if there is a lot of sugars remaining. Your taste of very sweet grains suggests you are leaving a lot behind. Slow the draining down to reduce channeling in the grain bed, and maybe consider centralising the false bottom a little more, though I would put that down as a low priority.

Get some tools to measure temperature, volume, grain weights and gravity if you dont have them already.

Cheers


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## mr_wibble (27/9/13)

The 2x thermometers are on the way

So for the next brew (might make Tony's dunkel-weizen) I'll ...

- Adjust the recipe for 55% efficiency
- ask my LHBS wizard to double-mill the what malt
- verify mash water is at an accurate temperature
- verify target temperature of mash (add more, hotter water if low)
- mash for 90 minutes
- get some iodine and do a starch test (at 60 mins and 90 mins)
- run-off the wort slowly
- measure the SG of the 1st runnings
- verify the temperature of the sparge water-to-be
- verify the sparge temperature is hit (adjust with extra water)
- run-off the 2nd more slowly
- measure the SG of the 2nd runnings

Report back here.


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## wbosher (27/9/13)

Mr Wibble said:


> - Adjust the recipe for 55% efficiency


Not sure I'd do that. If you're going to do all the other stuff, that is likely to increase you efficiency quite a bit. Personally, I'd set it at maybe 65% and see how you go.


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## Dunkelbrau (27/9/13)

wbosher said:


> Not sure I'd do that. If you're going to do all the other stuff, that is likely to increase you efficiency quite a bit. Personally, I'd set it at maybe 65% and see how you go.


Nothing wrong with overshooting your target preboil gravity and volume.. Just recalculate your hop additions on the fly while heating the wort to boil.. More volume with correct gravities is a much more enjoyable brew session over coming short and having had the opportunity to add a little more grain.


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## fletcher (27/9/13)

slcmorro said:


> With an extended mash, are you blokes upping the temp a little to compensate? Say at 67c mash temp for 60 mins, bumped to 69c mash temp to counter the difference? Or just not worrying?


personally I wouldn't, as this can then affect the alpha and beta amylase in your wort. 

just record how much temp loss you normally get and go from there. I test my mash temp at 30 mins (halfway) for a 60 min mash, and then at 45 mins for a 90 min mash and adjust once. normally i'll only lose about 1C tops. YMMV.


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## Thefatdoghead (27/9/13)

Mr Wibble said:


> The 2x thermometers are on the way
> 
> So for the next brew (might make Tony's dunkel-weizen) I'll ...
> 
> ...


All of the above will deffinitly see your efficiency raised. You'll probably get a lower ph from the dark wheat malts as well. I don't know what your water profile is but I would guess your PH would be up around 5.6 to 6 with lighter grains. Just a guess though its deffinitly worth seeing what your mash PH is.


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## mr_wibble (27/9/13)

Gav80 said:


> [...]. I don't know what your water profile is but I would guess your PH would be up around 5.6 to 6 with lighter grains.


We're on tank water.

It is filtered, but only with a paper-type filter (which doesn't seem to be paper at all)


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## mr_wibble (27/10/13)

Ok ... here's the results ...

Brewed a smoked porter (no wheat in the grist) designed at a 65% efficiency.
I think I managed to be 68% efficient, since I managed a slightly higher final gravity 1.060 (for 19.2 litres) instead of 1.050 (for 22 litres) - once again, boiled too hard.

So looking at my list, here's what happened:





> verify mash water is at an accurate temperature


 - New digital probe thermometer matched reading of the big dial thermometer in the HLT within +/- 0.5 °C




> verify target temperature of mash (add more, hotter water if low)


 - Using the volumes calculated by BeerSmith, the 16.8 litres of water at 75°c gave me a mash temp of 78°C
- This was 78.9°C in the recipe, but the probe thermometer only reads in single degrees, so I stuck with 78.
i wasn't confident raising the mash temp by 1 degree with hotter additions anyway




> mash for 90 minutes AND
> Get some iodine and do a starch test (at 60 mins and 90 mins)


Yep did both of these.

Starch test was a bit of a darker brown at 60 minutes, but certainly less-dark at 90 minutes.
But nothing like when we tested against flour-water which was inky black, no brown at all.

I again measured the temperature of the mash at 60 and 90 minutes, it was a constant 68°C throughout.




> run-off the wort slowly


Yeah did this, sounded like a urinal, and took ages.




> measure the SG of the 1st runnings


1.084





> verify the temperature of the sparge water-to-be


There was two parts to the sparge according to my brewsheet 5.4 litres, and then 16.5 litres
The recipe wanted these at 76.5°C (or is that BeerSmith?), I had the first at 74°C, and then the 2nd at 79°C.





> verify the sparge temperature is hit (adjust with extra water)


This gave me a sparging-mash temperature of 66°C, and then 73°C - I guess it cooled while I had the lid off.
I don't know if this is OK - what should the mash temperature be during sparging?!




> run-off the 2nd more slowly


Did so.





> measure the SG of the 2nd runnings


2nd Runnings (the 5.4 litres) was 1.050
3rd Runnings (the 16.5 litres) was 1.020

I boiled for 60 minutes, giving me about 19 litres into the fermenter (not 22) at 1.065 SG

I have since diluted this with cooled boiled water (3.85 litres) to 1.050.

I worked out that perhaps I achieved a slightly better efficiency ... maybe about 68%.

I think the 2-part sparge helped with this, and I left the sparge water on the grain for (guess) 10 minutes before running off much slower.

Attached are a few photos of the process (if I can get them to work).


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## BeerNess (27/10/13)

Great to hear back! You can enter your actual boil off rate into beerSmith so it can give you better mash and sparge water volumes, fantastic to hear that your numbers matched up a lot better this time! I'm sure over time and practice (with accurate records ;-) ) your efficiency will stabilise, probably around 70%. But what ever efficiency as long as your brewing software and results match up you'll be golden! Good luck and happy brewing! :-D!


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## Adr_0 (27/10/13)

Mr Wibble said:


> Ok ... here's the results ...
> 
> Brewed a smoked porter (no wheat in the grist) designed at a 65% efficiency.
> I think I managed to be 68% efficient, since I managed a slightly higher final gravity 1.060 (for 19.2 litres) instead of 1.050 (for 22 litres) - once again, boiled too hard.
> ...


I think the crush looks good - husks aren't too torn up, and the endo-thingies are broken up nicely. I assume there is some flour at the bottom? Make sure you add this to the mash.

Was your mash temp 78°C or was that a typo? Most single infusion mashes are in the 65-69°C range. Some people stir once through the mash, but don't do any more than this as you will lose heat each time you open the lid - this includes each time you check your temp with a thermometer.

Your sparge water should be 75-80° ideally. The only, single function of this is to transport the sugars out of the mash tun and into your boiler. Hot is good as it thins everything out and makes it easier to drain. You will notice if you drain too quickly, as the grain bed starts to compact and the flow slows right down, with the wort only going through the path of least resistance. You basically have you play it by ear and just monitor your grain bed - you can always try to flow quickly and see what happens if you really want.


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## mr_wibble (28/10/13)

Adr_0 said:


> I think the crush looks good - husks aren't too torn up, and the endo-thingies are broken up nicely. I assume there is some flour at the bottom? Make sure you add this to the mash.
> 
> Was your mash temp 78°C or was that a typo? Most single infusion mashes are in the 65-69°C range. Some people stir once through the mash, but don't do any more than this as you will lose heat each time you open the lid - this includes each time you check your temp with a thermometer.
> 
> Your sparge water should be 75-80° ideally. The only, single function of this is to transport the sugars out of the mash tun and into your boiler. Hot is good as it thins everything out and makes it easier to drain. You will notice if you drain too quickly, as the grain bed starts to compact and the flow slows right down, with the wort only going through the path of least resistance. You basically have you play it by ear and just monitor your grain bed - you can always try to flow quickly and see what happens if you really want.


There was a little bit of flour ... bugger all really, but the whole lot went in.

Yeah, the mash temp was 68C ... I can't edit the post now, *sigh*.

thanks,
-kt


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## Adr_0 (28/10/13)

Mr Wibble said:


> There was a little bit of flour ... bugger all really, but the whole lot went in.
> 
> Yeah, the mash temp was 68C ... I can't edit the post now, *sigh*.
> 
> ...


You could go finer in the crush then, and in hindsight you have some headroom on the husks to go finer. That will probably help, I have definitely gone a lot finer than that without issue on a similar setup I have for my pilot batches (the false bottoms work well).

I would hazard a guess that your lautering efficiency is 100% fine - nothing more to do there, but...

Your iodine test still looks to have a lot of starches in it. Is your pH really 4.6-4.8? Tank water probably is great water for brewing, but needs hardness in the form of calcium carbonate and a bit of calcium sulphate. Try EZ water or Braukaiser's water calculator.

Otherwise, how are you calculating your efficiency? Your efficiency cannot change when you stop sparging and have your preboil as you are not changing sugar content past this, but your brewing numbers can look like it one of the following is off:
- Leftover volume from trub/hops is too high
- Boiloff is off (if it's too high the SG ends up about right but volume is too low, disguising lower mash efficiency)
You should change these numbers to get the right volume/SG in your beer design once you have measured your mash efficiency (conversion + lauter) and input this into the software. Don't change the efficiency to get these numbers to look correct.

Good luck...


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## Adr_0 (28/10/13)

actually... did you add anything to get pH 4.6 or was that just the mash pH?


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## Thefatdoghead (28/10/13)

Nothing wrong with a 68% efficiency. What was your mash PH? I'm guessing that photo of PH 4.6 is your rain water?


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## mr_wibble (29/10/13)

Adr_0 said:


> actually... did you add anything to get pH 4.6 or was that just the mash pH?


No, didn't adjust the water. 
That was the mash pH. 

I assume the water pH is 7, the only minerals it would get is dust off the roof.


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## Spiesy (29/10/13)

I get around three "pellets" per session in the crapper.


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## Adr_0 (29/10/13)

Where do you live? Apparently rainwater can be quite acidic. Don't live near a power station do you?

The mash pH it slightly outside the ideal 5.2-5.5 range and would also be lacking calcium. The pH means that the enzymes just work slower, and the calcium has a number of carry-on effects including clarity, hop utilisation, yeast health and wort fermentability... apparently.

Regardless, the iodine test seems to show starch still. Can you do a hardness and alkalinity test on your water? Probably very very low and I would say you need to put in some calcium carbonate to help buffer the pH (keep it stable) and potentially some calcium sulphate for more calcium and to prevent the beer being too 'soft'.







Just further on what I said previously, I would say your lauter effieincy is very good. I only do a single sparge and get 74-78% fairly consistently. Efficiency is not a measure of self-worth, but you might as well get some value out of your grains and then figure out what works for you process-wise and what gives you the most consistency.


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## Adr_0 (29/10/13)

Spiesy said:


> I get around three "pellets" per session in the crapper.


What does that put your efficiency at?


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## billygoat (29/10/13)

Mr Wibble said:


> No, didn't adjust the water.
> That was the mash pH.
> 
> I assume the water pH is 7, the only minerals it would get is dust off the roof.


Rain water absorbs CO2 as its falling which drops the pH. I have three different tanks and they each have different pH readings and they also vary on the amount of rain we've had and how long since it rained. I always use the same tank as its cleaner water being further away from trees etc. Over the last couple of years I have measured it each brewday and it has ranged from 5.5 to a touch over 6. Even though it varies a bit, my mash pH is more effected by the grains used and the salts I've added.


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## Adr_0 (30/10/13)

billygoat said:


> Rain water absorbs CO2 as its falling which drops the pH. I have three different tanks and they each have different pH readings and they also vary on the amount of rain we've had and how long since it rained. I always use the same tank as its cleaner water being further away from trees etc. Over the last couple of years I have measured it each brewday and it has ranged from 5.5 to a touch over 6. Even though it varies a bit, my mash pH is more effected by the grains used and the salts I've added.


What would be an example of added salts for a pale ale? Do you get much joy with calcium carbonate or does bicarb soda work better?


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## billygoat (30/10/13)

Adr_0 said:


> What would be an example of added salts for a pale ale? Do you get much joy with calcium carbonate or does bicarb soda work better?


I add my salts to the total water (mash and sparge) in the HLT, usually 44 litres which leaves some left over at the end of the sparge depending on brew length, boil time etc. The additions for an American Pale Ale would typically be 14g of Gypsum, 4g of CaCl2 and 5g of MgSO4.
I have tried chalk and sodium chloride but don't bother now.
For other styles I change it up a bit and reduce the Gypsum and up the CaCl2.
If using only Pilsner malt I have just started adding some acidulated malt to the grist as my pH was closer to 6 when pilsner only.


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