Easy Partial Mash Brewing (with pics)

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Pour it in through a funnel after it cools. It splashes alot, which is good at that stage...you want aeration so you can get oxygen in the wort for the yeasties to eat up while they go through their reproductive stage.
 
I know it's been asked but I don't think it's been answered. Hey I'm a nube to the group though.

I have a wheat kit from Austins (the mini mash Belgian White) and it asks for 2.5 gal for mash and 3 qrts for the sparage water. The total grain bill is 2.75 lbs. I'm think'n more along your lines of 1 gal of mash water and 3 gal of sparage water. Would this make this a better (and true to form) PM?

I've had this kit for a week and really need to get it done so I can try your Dunkel recipe.
 
Back reviewing the guide for my next beer...such a great guide!

I just ordered a new 60qt brew kettle (In preparation for full boils and double batches). This may be a dumb questions, but is that pot going to be too large for this method to boil in? I would still do my mash in the smaller 5 gal pot.

Thanks.
 
Hey Death Brewer,

I tried this method for my witbier the other day, but got terrible efficiency(not sure the exact number, but my OG was 1.036 and was supposed to be 1.044). Not a big deal, just added more extract

Which of these mistakes that I made, do you think could have been the cause(if not both)

1. I was using a really thin Stainless Steel pot that would not hold heat. So, the heat dropped to as low as 140 and jumped as high as 164 during the mash, before I found a way to regulate it properly.

2. I may not have stirred it well enough before trying to hold the temp, and I definately didn't stir at all while mashing. Will stirring during the mash increase my efficiency?
 
1. Yes, fluctuations in temp can cause poor efficiency, especially if you are killing enzymes (close to that with 164°F.) Hitting your temp the first time is something that takes a little practice. Regulating temp using a burner is not recommended, as your temps will jump up and down and using a glass thermometer for reading will throw it off with hot and cold spots.

I recommend keeping boiling water on hand in case you need to raise your temp. If you need to lower it, put some cold water in. No matter what, add a little at a time, mix well, and let it sit covered for a minute before reading the thermometer. Only then will you get an accurate reading. Some software can help you to know exactly how much boiling water to add to get to your desired temp.

2. I generally only stir once or twice during the mash. Once I see I am at the right temp, I just let it sit. Mixing will increase efficiency and speed up the process, but it is not necessary...those enzymes will find their way to the starches...and I think maintaining the right temperature is more important, flavor-wise.

Time might be more of a factor...how long did you mash?
 
Back reviewing the guide for my next beer...such a great guide!

I just ordered a new 60qt brew kettle (In preparation for full boils and double batches). This may be a dumb questions, but is that pot going to be too large for this method to boil in? I would still do my mash in the smaller 5 gal pot.

Thanks.

That should be fine. You might have trouble attaching the bag and if you are using a stove-top, there might be problems with bringing it to a boil.
 
\Time might be more of a factor...how long did you mash?

I mashed for 60 mins.

I did regulate with my burner though. Also, my mash looked a lot thicker than yours. I didnt account for the rice hulls on my water to grain ratio, so that might have been a factor.

Thanks for your response Im going to try this again soon using boiling water to add heat if I need it and try mashing a bit thinner and mixing a bit better.

Is there anything you can recommend that will help my thin SS pot hold heat better?

:mug:
 
Make an insulator that you can slide on once you reach temp. My buddy made one out of a windshielf reflector. I've wrapped my pots in blankets in the past and now I have a wrap made out of actual insulation.

I rinse off the rice hulls before I use them. That will make them absorb some water so it doesn't mess up your ratio and it gets the dust off of them...I've found they aren't the cleanest product on the planet. You don't really need rice huls when using the bag method, and I rarely use them with wheat anymore, unless there are more adjuncts.
 
Make an insulator that you can slide on once you reach temp. My buddy made one out of a windshielf reflector. I've wrapped my pots in blankets in the past and now I have a wrap made out of actual insulation.


Yeeeah Buddy!! Just did an all grain 2.5 gallon batch and got 70% efficiency.

I built a little insulator out of a towel some tinfoil and masking tape. It held my temp even at 153. Thanks for your help!

:mug:

Here's a pic of the insulator I made. It was super simple and worked like a charm

brewpotinsulator.jpg
 
Quick question...due to shipping charges and time it takes to get here (want to brew friday) i was wondering if i absolutly had to have a grain/hop bag thats 24x24? and what kind of sack am i looking for? (ex. nylon steeping, mesh, etc..) to do this partial mash. This will be my first partial mash and ordered everything i need but they only had a 18x22 nylon steeping bag will this work?
 
If the grains will fit, it will work. I like the 24x24 because they wrap around the outside of the pot. You may have trouble with that, depending on the size of your pot and amount of grain. Other than that, it should work fine.

bgough...great insulator. I have one that looks similar. We used housing insulation and just taped the **** out of it to ensure no fiberglass will be exposed to the brew. Works like a charm.
 
great thread, thanks DB! Will be trying out this method on my next batch

edit: if I'm looking at an all-grain recipe and trying to convert it to partial mash, how close would i be if i:

1) take all the specialty grains and as much base malt as i can comfortably mash with the pots i have available
2) replace the rest of the base malt from the recipe with about 75% of their weight in DME

does that sounds about right?
 
great thread, thanks DB! Will be trying out this method on my next batch

edit: if I'm looking at an all-grain recipe and trying to convert it to partial mash, how close would i be if i:

1) take all the specialty grains and as much base malt as i can comfortably mash with the pots i have available
2) replace the rest of the base malt from the recipe with about 75% of their weight in DME

does that sounds about right?

I think it's 60%

0.6 lb DME = 0.75 lb LME = 1 lb Grain

But that's correct, just replace the base malt. You could choose an extract that matches the type of grain, too, to get even closer. American 2-row = Briess Light, Marris Otter = Muntons Light, Pilsner Malt = Briess Pilsner, etc.
 
I think it's 60%

0.6 lb DME = 0.75 lb LME = 1 lb Grain

But that's correct, just replace the base malt. You could choose an extract that matches the type of grain, too, to get even closer. American 2-row = Briess Light, Marris Otter = Muntons Light, Pilsner Malt = Briess Pilsner, etc.

Hmmm...is there a reference guide or database somewhere that lists all the different grain types along with their comparable extract??? (If not, there should be!)
 
It's not that tough...there are only a few base malts, so it's just trying to match the company or country of origin. British grain = british extract, etc.

Until you get into the "amber" and "dark" extracts. They may list what they put into it on their website, but I don't even want to screw around with trying to get the ratio perfect. I'll just wing it and make my own beer :)
 
Thanks for the thorough explanation and the pictures. I feel a little bit more confident about trying this down the road!

Thanks,

Jason
 
Wanted to say thanks for the all the effort put into the OP. I did a partial mash on on Wednesday following your steps. Target OD 1.067, I got 1.066. I was pretty happy with that. My step came over to help. He was like, there's a lot of down time between the steps LOL.

Side note, when I was puttin my blow off tube into the lid of my bucket the rubber grommet split so I don't have an air tight fit. I haven't had a chance yet to get to my LHBS (I work 12 hour shifts) but I tried putting some tape around it but I don't seem to be getting any bubbling. Looking in the little hole I can see what appears to be foam/kausen. Should I be that worried? Should pop the lid and take a reading see if it's dropped any? Should I just RDWHAHB?
-Thanks
 
Wonderful post, I read almost every page, thank you.

I will be using this for a wit on monday.
 
Question and it might already be in the 18 pages but I assume you turn the heat off when mashing for the 30-60 minutes. Do you have any problems with the mash going too low temperature?
 
OK...first attempt at partial mash and I used this method. I am pretty sure I messed up. Not that the beer will be bad. Just that I think I had really bad efficiency.


I had a problem keeping the mash between 150 and 155. When I put the grain in the 170F water dropped to 148. So I applied some heat and got it back to 154 and wrapped up the pot. 10 minutes later and the temp was down to 144. So I applied more heat and gave the mash some stirring. Then when I was back to ~154 I removed from heat and wrapped it up again. 15 minutes later I checked and the mash was at 161F. So left the lid off and stirred it for a little while. It some time but the mash returned to 153. Then I back to below 150.... You get the idea.


In the end when I checked the gravity of the 5 gal wort prior to pitching the yeast my reading was 1.040 (had hoped for something closer to 1.050). If the reading it correct then I believe I managed only 50% efficiency. Normally when I have brewed extracts and I missed my expected OG I'd just chaulk up as poor mixing or something like that.

Can poor mixing once again be the problem with a partial mash? My boil was only about 3gals.
 
Question and it might already be in the 18 pages but I assume you turn the heat off when mashing for the 30-60 minutes. Do you have any problems with the mash going too low temperature?


I dont think its a good idea to keep the flame on. I asked the same question.
I also have a cheap pot and had some problems with my temp dropping.

I made a simple insulator that worked like a charm. Deathbrewer said he made one out of actual insulation. Heres my post fom the page before...

I built a little insulator out of a towel some tinfoil and masking tape. It held my temp even at 153. Thanks for your help!

brewpotinsulator.jpg
 
Deathbrewer, is there any reason this couldnt work for a 5 gallon all grain batch in two 30 qt pots? I got a turkey fryer for $30 and am thinking about getting another one.
 
Deathbrewer, is there any reason this couldnt work for a 5 gallon all grain batch in two 30 qt pots? I got a turkey fryer for $30 and am thinking about getting another one.

I believe there is a thread somewhere where Deathbrewer demos how to do AG on the stovetop. Very similar in theory if I am not mistaken
 
OK...first attempt at partial mash and I used this method. I am pretty sure I messed up. Not that the beer will be bad. Just that I think I had really bad efficiency.


I had a problem keeping the mash between 150 and 155. When I put the grain in the 170F water dropped to 148. So I applied some heat and got it back to 154 and wrapped up the pot. 10 minutes later and the temp was down to 144. So I applied more heat and gave the mash some stirring. Then when I was back to ~154 I removed from heat and wrapped it up again. 15 minutes later I checked and the mash was at 161F. So left the lid off and stirred it for a little while. It some time but the mash returned to 153. Then I back to below 150.... You get the idea.


In the end when I checked the gravity of the 5 gal wort prior to pitching the yeast my reading was 1.040 (had hoped for something closer to 1.050). If the reading it correct then I believe I managed only 50% efficiency. Normally when I have brewed extracts and I missed my expected OG I'd just chaulk up as poor mixing or something like that.

Can poor mixing once again be the problem with a partial mash? My boil was only about 3gals.

Sounds like what I went through a couple hours ago. This was my second brew and my first partial mash. For the first 20 mins it was up down up down. For a while hovering around 160, then I put water in to chill, and overshot and it got in the 140’s. Then I heated it up again, but too much. Finally got it to level out at 155 and I wrapped it in a towel wrapped in tinfoil (as seen in this thread) but over the rest of the hour it dropped (I think I need a thicker towel and more tinfoil). Went down to the low 140’s near the end but I said the heck with it, I did an iodine test and there was full conversion at that point anyway.

I was shooting for 1.050 but got 1.042. Guess that works for a wit?

I won’t be too hard on myself, it was my second beer and there was no sign of any starch and I had a lot of fun. I think this is an awesome method and I can’t wait to make my third beer (a porter) with it in a few weeks.

Mahalo DeathBrewer
 
'A'ole pilikia

I've often had the temp drop when I have too much headspace and/or not enough insulation. It always seems to go down to 140°F and stick there. I wonder what that's about. In any case, it still made fantastic beer :)

More important is hitting your temp the first time. It still takes some getting used to and changes a little with different equipment, but you can get a better handle on it by using promash or this calculator:

Green Bay Rackers--Mash Calculators
 
Deathbrewer, is there any reason this couldnt work for a 5 gallon all grain batch in two 30 qt pots? I got a turkey fryer for $30 and am thinking about getting another one.

There is a link in my sig for stove-top all-grain. Two 30 qt pots will work fine. I use a 5 gallon pot for the mash so there is less headspace and less heat loss, but it limits the amount of grain I can use, so it is only for smaller beers. A 30 qt would allow you to do any size beer, although you might strain your back lifting that heavy bag. ;)
 
Alright so last night my roommate and I did our first Partial Mash using this technique. It went alright but im pretty sure my conversion wasnt very good. We had to split the sparge water into 2-2gallon pots due to not having a 3 or bigger gallon pot to sparge (what do u think deathbrewer?).

So we had the same problem with getting the temperature to stay consistant pretty much most the mash period. I used a floating thermometer for the first time and probably wont use that thing again because of how many hot and cold spots those things hit. It looked like everytime i took a reading it would vary 10-15 degrees everytime. Sometimes it would say as low as 140 and other times as high as 165 maybe even 170 at times. Lesson learned but how do u manage to keep the temp in a 5 gal pot with only 2 gals of water? Seemed the headspace was way to much and thats why the temp keeps changing.

We brewed blacklab's (i think) cascades/orange pale ale and boy did it smell good during the brew. I forgot to take a gravity reading and had already pitched the yeast and thrown the airlock on so i wont be able to do the conversion math but im sure its pretty low. We did 10 minute sparges in each of the 2 gallon pots with 1 gallon of water so it sparged for 20 minutes. I figured this might help the efficiency out a little bit. Any ideas as to how this might turn out?
 
I've found that the glass thermometer is the best tool for reading the temperature of the mash. Any other thermometer will also be subject to hot and cold spots.

One reason for getting wild readings is impatience or being overly concerned. Calculate your strike water so you should be in the neighborhood of your intended mash, mash in and cover for at least 5 minutes. This will allow the temperature to stabilize and you should get an accurate reading. If you need to correct, add a small amount of hot or cold water, stir well and let it sit for another 5 minutes before checking the temp again.

I'm sure it will turn out fine...it would be nice to know what your efficiency was, however, or it's all speculation. Why do you think you got poor efficiency? Bobby_M has a thread regarding double-batch sparging, which is what you did in essence. It increases efficiency.

And everyone, please don't worry too much about your mash temp dropping. Get it in the range you want, keep it covered, and let it sit. As I've said many times, I've often had my partial mash batches drop down to 140°F by the end of the mash. I've never experienced any off flavors or poor conversion due to this...simply a drier beer, which I prefer ;)
 
DeathBrewer said:
7 lbs of grain with 2.5 gallons of water (1.43qt/lb) gives you a total of 3.06 gallons for your mash

Is there an easy way to guesstimate how much grain/water you can fit in a X-sized pot? I have a 24qt currently for extract brewing and I am thinking of getting a larger pot for full boils while using the 24 for mashing.

Would I be able to get away with, say, 8 or even 9 lbs of grains in there?

edit -- just answered my own question - the calculator linked a couple posts up has a function for this. Cool!
 
So its been approximatly 30 hours and its been my most vigorous fermentation yet ( 3 extract, this one Partial Mash) of course this is only the second time i have used dry yeast. Two of my extracts were wyeast liquid yeast and were good ferments but not very vigorous. Any chance its because there was a decent conversion and the yeast have plenty of sugar to feast on from the malt? (yeah i know i forgot to take a hydrometer reading....it was a long drunken night the night before so brew day was rough but still fun)
 
Honestly, no way of knowing. I'm sure it'll be good, tho. Chalk this one up to experience, enjoy the beer and be sure to take that gravity reading next time.
:mug:
 
I just tried this method tonight, with some modification. I only have one kettle, so after mashing, I racked the "first runnings" to a bucket, then lautered in the kettle and racked the first runnings back into the kettle once the grains were removed.

I'm a little stymied by my hydrometer reading, though. My grain bill was:
  • 5 lb American 2-row
  • 6 oz Crystal 40L
  • 2 oz Belgian Special B
  • 5.25 lb DME

With an assumed efficiency of 70%, some software (beer tools pro) tells me I should have gotten an OG of around 1.072. But I'm measuring more like 1.080, which implies an efficiency of ~90%! This really can't be right, somehow. It's fine to take a hydrometer reading directly from a wine thief cylinder, right? It's not too narrow or anything? Is there a certain amount of time one should wait (for the heavier particles to fall to the bottom of the carboy) before taking the OG reading?
 
It could be a poor mixture of DME or you could have ended in a little less than 5 gallons.

Or it could be right. I often get close to 90% efficiency when I do large scale brewing and it has happened before with this system (but not common.) Just make sure you mix very well when using extract. Particles aren't really a problem.
 
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