Maintaining mash temp

[toddo97]

I have two BIAB brews under my belt and am getting ready to brew this weekend. I mash on my electric stovetop and rather than doing the blanket wrap thing to maintain my mash temp, I just set the burner on low and frequently stir for the hour. My temps stay pretty steady and since it's low, there's no scorching/melting of the bag. Is this a legit thing to do or am I asking for trouble doing it this way? It seems like a good way of maintaining temps, but I don't see many (any?) people doing it like this.

 

[LittleRiver]

Some people put their pot in the oven to maintain temp. Or you could continue with your stovetop heating/stirring, there's nothing wrong with that.

I like the simplicity of just insulating the kettle, plus it frees up my time to go do something else during the mash.

 

[El Nino]

I never put an insulator on mine, and the temp only changes by 2 degrees at the end of 60 mins. Though usually in my mash the kettle is filled to the brim, I have less than an inch of headpsace with the grains all in there (doing 2.5 gallon batches in a 5 gallon kettle, usually cuts it close but no problems so far)

 

[toddo97]

I looked into doing the oven thing, but my oven only gets down to 175 so I figured rather than heating it to 175 and letting it cool a bit, stirring it on low would be easier. I'm too new to trust walking away and doing something else while it's sitting so I don't mind stirring on low for an hour and hanging out with the mash

 

[LittleRiver]

...I don't mind stirring on low for an hour and hanging out with the mash

It sure sounds like you are enjoying your brewing. Well done. That's what it's all about.

 

[wilserbrewer]

I looked into doing the oven thing, but my oven only gets down to 175 so I figured rather than heating it to 175 and letting it cool a bit, stirring it on low would be easier. I'm too new to trust walking away and doing something else while it's sitting so I don't mind stirring on low for an hour and hanging out with the mash

The oven does not need to be at mash temp for that method to be effective.
Even at 175, the oven temp is a helluva lot closer to mash temp than ambient, and might result in your mash gaining a couple few degrees.

What I would suggest, is warming your oven and putting your mash kettle in to rest, then turn off the oven and ignore it. If you end up losing a little heat this way, leave the oven on a little longer or vice versa.

The idea of the oven method is based upon the oven being a much closer temp to mash temp, not the exact temp. I think you will find the oven method easier than stirring, heating, checking temp, or also known as baby sitting your mash...not fun imo

 

[eric19312]

I think stirring at least occasionally helps efficiency. When I mashed in a cooler this was true. Now I mash in a direct fire recirculating kettle and still find an efficiency boost from stirring once or twice during the mash.

 

[toddo97]

After I get a couple of more BIAB batches under my belt, I can try comparing efficiencies between the two methods. When you let it sit for the mash, either in the oven or wrapped in blankets, aren't you supposed to stir it ever 15 minutes or so?

 

[bleme]

After I get a couple of more BIAB batches under my belt, I can try comparing efficiencies between the two methods. When you let it sit for the mash, either in the oven or wrapped in blankets, aren't you supposed to stir it ever 15 minutes or so?

I preheat my oven to 170F, turn it off, and put my mash in with a thermometer. I set the alarm on the thermometer to tell me if the mash drops more than 2 degrees. If it does, I'll turn the oven back on for a few minutes then give the mash a stir to even out the temp. I usually only have to do that once.

A couple of times I have gotten a call and had to leave the house for a few hours. The mash might drop as low as 140F by the time I got back, but still turned out fine.

 

[boxboybrewing]

I'm using an 8 gallon tamale steamer pot (minus the false bottom) as my BIAB mash and boil kettle. I've noticed if I insulate it with a large towel wrapped around it, it actually GAINS a few degrees at the first of the mash. So, I don't insulate it for the first 20 minutes or so.

 

[wilserbrewer]

After I get a couple of more BIAB batches under my belt, I can try comparing efficiencies between the two methods. When you let it sit for the mash, either in the oven or wrapped in blankets, aren't you supposed to stir it ever 15 minutes or so?

Stirring every 15 minutes just gives the brewer something to do imo. More or less...

Stir well in the beginning, and stir more well at the end and I’m sure the mash sugar will be uniform in the mash.

Stop trying to over analyze imo.

 

[IslandLizard]

After I get a couple of more BIAB batches under my belt, I can try comparing efficiencies between the two methods. When you let it sit for the mash, either in the oven or wrapped in blankets, aren't you supposed to stir it ever 15 minutes or so?

Most efficiency will be gained by getting a fine crush, not so much by mash temps (as long as they are within range). Mash temps primarily influence the fermentability of the wort.

To raise your mash efficiency, simply mill finer.
For BIAB you can use a relatively fine milling gap, since the bag is your lauter filter. Mash efficiencies as high as 85-90% can be easily attained.

If you get your grain from your local brew store, mill them twice. Some places will set the gap narrower upon request, which is even better, but most won't even consider touching their overly wide gap. For that reason, at some point people buy their own mill to be in full control over their crush.

 

[cmybeer]

I always liked the idea of stirring or recirculating in some way to maintain a consistent temp. There have been times in the past that I've "nailed" my temps only to stir it and find the temp plummet because it was colder on the outside. Depending on the your style and starting temp those degrees matter unless you want a light bodied stout.

 

[wepeeler]

I just made this for my kettle. Testing it out on Thursday. I used to use just an old sleeping bag, and I'd lose anywhere from 2-4 degrees. Even if this helps a little, it was worth it. Made it 2 layers thick. Might have to wrap a 3rd time.

http://fermware.com/reflectix-insulation-jacket-for-your-mash-tun/

 

[nymtber]

I made a reflectix coozie for my kettle. Double layer with a double layer lid. Use aluminum ducting tape only!

IN WINTER I lose 4°F over an hour in my enclosed porch (not insulated). Last brew was about 2°F with outdoor temp around 50°F.

Well worth the cost... Maybe $20

 

[PrrCabin]

I made a reflectix coozie for my kettle. Double layer with a double layer lid. Use aluminum ducting tape only!

IN WINTER I lose 4°F over an hour in my enclosed porch (not insulated). Last brew was about 2°F with outdoor temp around 50°F.

Well worth the cost... Maybe $20


Sounds interesting.
Do you have any photos of this coozie?

Cabin

 

[Foosier]

I agree with Wilser... Wrap your kettle and walk away. BIAB is all about simplifying the process. it will make just as good of beer as more complicated methods if you keep track of what is important. Besides, if you lose a degree here or there in the mash, it will be fine. It really won't matter unless you drop out of the enzymes preferred range, which is unlikely.

 

[mongoose33]

When I started to stir at 15 and 30 minutes, my efficiency went up quite a bit. Some of what people experience will be dependent on crush and temp and malt and so on. If it's a very fine crush, most of the conversion will be done by 15 minutes; if coarser (something LODO brewers do), then there's a benefit from either stirring or recirculation.

There's another benefit of stirring: creating more homogeneous temperature throughout.

My biggest concern with using an oven--which isn't a bad idea from the temperature point of view--is lifting a kettle with 7 gallons of water plus grain off the stove and into the oven.

FWIW: when I use my cooler mash tun in the winter, the garage is always pretty cool. I have used a heat mat under it as a way to prevent a lot of temp loss through the bottom as it sits on a cold surface. One could also wrap a cooler fully or partially with a heat mat as a way to help maintain temp.

 

[RM-MN]

I have two BIAB brews under my belt and am getting ready to brew this weekend. I mash on my electric stovetop and rather than doing the blanket wrap thing to maintain my mash temp, I just set the burner on low and frequently stir for the hour. My temps stay pretty steady and since it's low, there's no scorching/melting of the bag. Is this a legit thing to do or am I asking for trouble doing it this way? It seems like a good way of maintaining temps, but I don't see many (any?) people doing it like this.

Here's my opinions.

1. Mash temps are only important while conversion of the starches to sugars is going on. That conversion is really quick but until the starches get wet (gelatinization) nothing happens. How finely your grains are milled determine how quickly all the starch gets wet. With fine milling that happens very quickly and conversion is completed in less than 10 minutes. Coarser milled grains take longer to get the starches all wet. That coarser milling that is required for a conventional mash tun is why the hour long mash was started and with really coarse milling that isn't enough yet. Since you are BIAB, you can deal with a much finer crush so the hour isn't necessary unless you are stuck with the milling done at your LHBS.

2. Adding heat slowly so you don't scorch the grain/melt the bag is a viable technique but you need to stir nearly constantly as the grains in the water restrict the movement and it is really easy to get part of the mash too hot which then denatures the enzymes that cause conversion. Stirring also requires that there is no lid on the mash tun and that is where most of the heat is lost. Just put the lid on an leave the heat off and you will probably get the same result.

 

[angry_gopher]

I have two BIAB brews under my belt and am getting ready to brew this weekend. I mash on my electric stovetop and rather than doing the blanket wrap thing to maintain my mash temp, I just set the burner on low and frequently stir for the hour. My temps stay pretty steady and since it's low, there's no scorching/melting of the bag. Is this a legit thing to do or am I asking for trouble doing it this way? It seems like a good way of maintaining temps, but I don't see many (any?) people doing it like this.

This is what I’m doing, my Insulated hunting jacket. Now it’s useful year round!

 

[mongoose33]

View attachment 576491

This is what I’m doing, my Insulated hunting jacket. Now it’s useful year round!

You have the burner on while the jacket is wrapping the mash kettle?????????

 

[angry_gopher]

You have the burner on while the jacket is wrapping the mash kettle?????????

nope, that would be silly.

 

[rkhanso]

nope, that would be silly.

Hey, whatever works....
Do you wash you jacket before hunting season to get the beer smell out of it?

 

[RM-MN]

Hey, whatever works....
Do you wash you jacket before hunting season to get the beer smell out of it?

Would it be considered baiting if the beer smell wasn't washed out?

 

[wilserbrewer]

Would it be considered baiting if the beer smell wasn't washed out?

Likely not in a legal sense, cause the actual bait needs to be physically present, at least in my grounds.

I had a bottle of “doe scent” and the warning on the label was so funny....
That’s a tough day of hunting getting physically attacked by a buck in rut trying to have his way with you lol.

 

[Korken91]

I have to say about the oven method, I told my freind to use it on he's second brew, first alone. So he did, and he also did the boil in the oven... So you could (depending on oven) mash, take the bag out and boil in the oven apparently.

 

[rkhanso]

You've got me thinking....I'm into grilling and smoking and have a temperature controller for my Kamado Grill. My DIY (Heatermeter) charcoal grill temp controller would keep the temp at a constant mash temp and also boil.
Now, the brand/size of my grill isn't large enough to hold my 25gal brew kettle, so I think I may not be able to give this a try.
But, I wonder if anyone else has tried brewing beer on a smoker and how that would turn out. A 10 gal kettle may fit on my grill/smoker.
I might have to think about this a little more.

 

[Jayhawkrob]

I would pity the person who gets a boilover trying to brew on a kamado. The thermal shock on the ceramic would probably make for a pretty nasty crack at best and a shattered mess of charcoal on the ground at worst.

 

[Shawn3997]

Sleeping bag from Wal-Mart: $30. In the summertime I don't even lose a degree.

 

[LittleRiver]

Sleeping bag from Wal-Mart: $30. In the summertime I don't even lose a degree.

Same here. I brewed yesterday and did not lose a degree over a full hour.

Except in my case I didn't even spend $30, I used an old army mountain sleeping bag given to me by my uncle. It was probably made in the 1960's.

 

[Foosier]

You can go even cheaper. Get a movers blanket from Harbor Freight. They are dirt cheap and work great at insulating your kettle. Easy to replace if it gets destroyed too.

 

[shetc]

Reflectix is totally kick ass. I do a 90 minute mash and temp drops at most 2 degrees.

 

[RM-MN]

Reflectix is totally kick ass. I do a 90 minute mash and temp drops at most 2 degrees.

Have you considered exactly why you do a 90 minute mash? Does your mash really take that long to convert?

 

[RustyBumper]

I went to a 30 min mash and wrap with a Asian mink blanket. Gravity has been good so far.

 

[shetc]

Have you considered exactly why you do a 90 minute mash? Does your mash really take that long to convert?

I'm very conservative [emoji1]

https://www.biabrewer.info/viewtopic.php?p=42947&sid=449c5d262009eaf8a535b2d0e2252148#p42947

 

[angry_gopher]

I'm very conservative [emoji1]

https://www.biabrewer.info/viewtopic.php?p=42947&sid=449c5d262009eaf8a535b2d0e2252148#p42947

Don't you mean 'convertative'

 

[jiMithing83]

Reflectix is totally kick ass. I do a 90 minute mash and temp drops at most 2 degrees.View attachment 579566

I'm thinking of doing a reflectix wrap myself, how many layers did you go with? I'm hoping to get away with just 2 layers.

 

[shoengine]

I found when actively heating the mash I get conduction running up the sides of the pot giving me at least three or four different temperature zones. In the end, I just went back to sleeping bag wraps.

 

[shetc]

I'm thinking of doing a reflectix wrap myself, how many layers did you go with? I'm hoping to get away with just 2 layers.

4 layers around the kettle and 3 to make the lid. I used a hot glue gun to stick the layers together. Not shown here is a bungee cord to hold it close. The trick is to put it on as soon as you turn off the heat then mash in.

 

[Cevan65]

I don't even use reflectix anymore on the sides. I do use two layers on the lid. I mash for 45 minutes (I measured almost no gain in going to 60 min) and I stir at 15 and 30 minutes. I lose about 2 degrees at most. I do this on my stovetop and the burner (electric stove) is still warm once I get the strike water to temp so I imagine this helps reduce the loss of heat. My brew kettle also has very little headspace once the mash starts.