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Having trouble with mash temps and whirlpool

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FatDragon

Not actually a dragon.
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I just did my third BIAB batch yesterday, and for the third time, I've had trouble with my mash temps. The first batch attenuated at least 0.006 below the anticipated FG (of a popular HBT recipe), and with the second and third batches I've found thermometer readings swinging wildly (5-6 degrees Celsius) just from a little bit of stirring.

I'm doing ~5 gallon batches in a 9 gallon pot on my kitchen stove (natural gas).

The beauty of BIAB is simplicity. Is there a simple way to get a more even mash temperature, or at least a tried and tested method for achieving mashing goals in a kettle with such varying temperatures?

Secondarily (don't want to start a separate thread), how does one effect a whirlpool to create a trub cone for more efficient siphoning? I've used Whirlfloc at 15 minutes and stirred until the mostly-cooled wort was spinning in a whirlpool and covered for half an hour, but both of my attempts have left me with the same two inch bed of cold break that I got with my first two brews that I didn't whirlpool. What am I doing wrong here?
 
I think a cone would form when using hop cones to give the pile some structure.

Try stirring the mash more to get temps more even. I've never done biab, but I wonder if the pot is small and mash thick.
 
Stop stirring your mash. You only need to stir when you add the grains and then you stir really well to get them all mixed in. Then you put the lid on and insulate the pot with something like a bath towel and walk away.

When you open the lid of the pot to stir, you lose heat. When you stir you lose even more. You don't need to stir once the grain is in.
 
Okay, so for mash, I should stir less and try to do a better job of insulating the kettle? Makes sense for maintaining consistent temperatures (though not necessarily even through the pot) but I thought stirring BIAB was supposed to increase efficiency by giving the grain more contact with the water? I'm definitely struggling with efficiency (~60%), so I don't want it to get even worse; my next attempt, I'm going to tighten my Corona mill as tight as it can get while still being able to turn.

And for the whirlpool, does it really only work with cone hops? I feel like a lot of people whirlpool and most people use pellets, so I would be surprised if I had to use cones (which aren't available to me) to get the proper trub cone.
 
If you bag the pellets perhaps the break will have a stronger coagulation.

Is there any reason for this? I would think that hops, even pellets, would be a bit more solid than the gelatinous/plasmic cold break, thus giving a better shot at coagulation. However, I'm wrong a lot when it comes to anything physics related, so I could very well be wrong here.

In future brews, if I continue to fail to get a trub cone, I'll probably just toss the whole thing in the fermenter, maybe through a BIAB bag for filtration. My thinking there being that there's a lot more time for the trub to settle in the fermenter, so I'll end up with more beer that way, even if I have more trub to deal with. Since I'm neither washing yeast nor pitching directly on previously-used yeast cakes, it's not really a big deal to leave a bit of extra trub, is it?
 
I can't tell the difference between adding and removing trub from the fermenter. Though I have yet to compare side by side.

The reason I think pure break might bond better without hops is based on observations of the break material without hop particles present. I am able to tip the kettle quite considerably to extract liquid while the bonded break material stays put. This doesn't happen when I throw the pellets in loose.
 
I can't tell the difference between adding and removing trub from the fermenter. Though I have yet to compare side by side.

The reason I think pure break might bond better without hops is based on observations of the break material without hop particles present. I am able to tip the kettle quite considerably to extract liquid while the bonded break material stays put. This doesn't happen when I throw the pellets in loose.

Well, it certainly can't hurt to give it a try in my next brew.
 
You can definitely stir during the mash; moving the wort during mash is how a RIMS system works. The problem you're going to have is keeping the temperature consistent while doing so. I BIAB and "regular" mash, and when I BIAB I always stir it and have never had problems. I keep a close eye on my temps and will add a bit of heat if I need to. Make sure you ALWAYS stir if you add heat, otherwise you will get temperature stratification and the bottom will be WAY over temp.

I, too, have always had the whirlpool problem--nothing I tried would create an effective trub cone. You don't have to use whole hop cones to get a trub cone, that's just silly. Any particulate matter will form a pyramid if whirlpooled properly. The problem is having such a large mass to get moving evenly. If you're like me, you've got temp probes and tubes jutting into the pot which makes it damn hard to get a smooth motion.

Both of these reasons are why I've decided to by a chugger pump. The pump will recirculate my mash and whirlpool my wort. I will mash for about 30 minutes, then during the last half hour I will recirculate. Using a temp probe installed after the wort leaves the pot, but before it enters the pump will allow me to keep control on the heat.

When it comes to whirlpool, I can just turn it on and let it do its thing for 20 minutes, then shut it off and let it settle. Using a pump will give me the power and uniformity that I can't get by hand.

That's my two cents.
 
You can definitely stir during the mash; moving the wort during mash is how a RIMS system works. The problem you're going to have is keeping the temperature consistent while doing so. I BIAB and "regular" mash, and when I BIAB I always stir it and have never had problems. I keep a close eye on my temps and will add a bit of heat if I need to. Make sure you ALWAYS stir if you add heat, otherwise you will get temperature stratification and the bottom will be WAY over temp.

I, too, have always had the whirlpool problem--nothing I tried would create an effective trub cone. You don't have to use whole hop cones to get a trub cone, that's just silly. Any particulate matter will form a pyramid if whirlpooled properly. The problem is having such a large mass to get moving evenly. If you're like me, you've got temp probes and tubes jutting into the pot which makes it damn hard to get a smooth motion.

Both of these reasons are why I've decided to by a chugger pump. The pump will recirculate my mash and whirlpool my wort. I will mash for about 30 minutes, then during the last half hour I will recirculate. Using a temp probe installed after the wort leaves the pot, but before it enters the pump will allow me to keep control on the heat.

When it comes to whirlpool, I can just turn it on and let it do its thing for 20 minutes, then shut it off and let it settle. Using a pump will give me the power and uniformity that I can't get by hand.

That's my two cents.

Have you ever done an iodine test to see if your mash is done? When I did, I found that conversion happened in much less than half an hour.
 
Okay, so for mash, I should stir less and try to do a better job of insulating the kettle? Makes sense for maintaining consistent temperatures (though not necessarily even through the pot) but I thought stirring BIAB was supposed to increase efficiency by giving the grain more contact with the water? I'm definitely struggling with efficiency (~60%), so I don't want it to get even worse; my next attempt, I'm going to tighten my Corona mill as tight as it can get while still being able to turn.

And for the whirlpool, does it really only work with cone hops? I feel like a lot of people whirlpool and most people use pellets, so I would be surprised if I had to use cones (which aren't available to me) to get the proper trub cone.

To get the best efficiency my Corona mill has its plates rubbing when empty. If I let them loosen just a little, my efficiency goes down. You want your particles of grain to be pretty small for the best efficiency. When you stir in the grain, it should have all the grain in contact with the water. More stirring won't get it any wetter.

If you have iodine available, you should do a test for conversion. It only takes a drop of iodine and a drop of wort. If the iodine/wort combination turns blue, you stilll have starch. When the color no longer shows any blue/purple the conversion is over and further mashing might only be making the beer more fermentable as the beta amylase keeps breaking down long chain sugars. At 30 minutes of mashing, my beers seem to be plenty fermentable as I typically get a higher OG than expected and a lower FG than predicted by the software.
 
To get the best efficiency my Corona mill has its plates rubbing when empty. If I let them loosen just a little, my efficiency goes down. You want your particles of grain to be pretty small for the best efficiency. When you stir in the grain, it should have all the grain in contact with the water. More stirring won't get it any wetter.

If you have iodine available, you should do a test for conversion. It only takes a drop of iodine and a drop of wort. If the iodine/wort combination turns blue, you stilll have starch. When the color no longer shows any blue/purple the conversion is over and further mashing might only be making the beer more fermentable as the beta amylase keeps breaking down long chain sugars. At 30 minutes of mashing, my beers seem to be plenty fermentable as I typically get a higher OG than expected and a lower FG than predicted by the software.

Alright, so my first order of business is tightening up my mill, then. That'll be easy enough. I'm also wondering if the cheap and potentially low-quality grain I'm using might have an effect, but at the same time I don't want to spend $60+ ($7.50/lb) for base grains for a test batch using the quality stuff (Briess, Weyermann, etc) that most of you are using, and I don't have a suitable pot to do a small test batch that would cost less.

Would PVP-I (Povipone-Iodine) Iodophor be suitable for the iodine test, or does it need to be pure iodine?
 
Alright, so my first order of business is tightening up my mill, then. That'll be easy enough. I'm also wondering if the cheap and potentially low-quality grain I'm using might have an effect, but at the same time I don't want to spend $60+ ($7.50/lb) for base grains for a test batch using the quality stuff (Briess, Weyermann, etc) that most of you are using, and I don't have a suitable pot to do a small test batch that would cost less.

Would PVP-I (Povipone-Iodine) Iodophor be suitable for the iodine test, or does it need to be pure iodine?

Other people have mentioned using Idophor but I have no experience with that. Give it a try. You could try it with a little corn starch in water so you'd know before you made a batch of beer. It should turn blue/purple with starches. It only takes a drop of each so don't mix up a big batch of corn starch.
 
Iodophor works fine for the conversion test, just be sure to throw away the sample. Too much iodine is poisonous for people and yeast alike.
 
I did my third BIAB this past weekend as well and while i did manage to get my efficiency up to 67% without double milling I did have trouble maintaining the mash temps. I hit strike temp at 166 and when I put the grain in the temps fluctuated quite a lot. I stirred the water before I put the grain in to get a good even mixture but still saw crazy temp mixing when the grain was in. This got me nervous as it would read anywhere between 145 and 165! So I stirred and let it sit, then stirred more, then let it sit, etc... I mashed for 90 mins and eventually got a solid reading of 152 and threw the lid on a said screw it I will wait it out (this was 45 minutes into the mash). My pot is a 10gal with the basket and a grain bag in that. Going to try again Friday I think, would really like to figure this all out, maybe it is just understanding your equipment? Open to any suggestions! Oh, and I smashed the absolute crap out of my grain after the mash to get everything out of it.
 
It took me several batches to figure out how to get my temps under control. At first I was constantly checking/stirring/adding heat, and my temps bounced around like crazy. Now I start a few degrees too high and stir like crazy until it comes down to the right temp, then cover it and don't touch it again until its done. I like to use my 5 gallon pot because I can put it in a pre-warmed oven, but if I'm using a bigger pot I zip my winter coat around it. I think having no head space in the pot helps too.

I don't understand the point of whirlpooling. I just pour it through a strainer, which aerates it and separates out the gunk at the same time.
 

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