Holding Mash Temperatures

[stone1ipa]

Greetings Fellow Brewers,
I'll be doing my first BIAB all grain in a couple of weeks and after reviewing a lot of threads and videos it looks like most of you insulate (in a variety of methods) to keep your mash temps close to desired state. However I've seen a few folks simply measure the temp occasionally and turn on their burners for a short period of time to get the mash temp back up. Does anyone know if using the burner option has any undesired side effects other than the hassle?

 

[DonGavlar]

Depending on your kettle, you may scorch the bag with the heat. If it has a cladded bottom then there's no issue. A way around would be to just make sure your bag isn't sitting against the bottom.

 

[auburntsts]

I could be wrong, but I don't think scorching a bag in a non-electric setup (ie no internal element) at mashing temps is much of a concern. Easiest solution is hit your mash temp, insulate, and let it be. That's what I do (albeit I'm small batch on a stovetop) and haven't had any issues.

 

[mongoose33]

Unless you stir once the heat has entered the mash, you'll get stratification in mash temps between bottom and top. The difference can be fairly significant. The grist acts to prevent convection as well as serving as an insulator.

I struggled a bit at the outset of doing BIAB because I have a Hellfire burner, and the burner retained a fair amount of heat which then transferred to the mash kettle. But in the end, simply by wrapping the whole affair well in a good blanket, I was able to keep temps from falling more than 2 degrees or so.

 

[LittleRiver]

Either will work, but I find that insulating the kettle is the way to go. I only add heat if it's really cold, and the temp has dropped more than I would like.

I find that a thermometer with a remote probe is nice to have, because I can monitor the mash temp without removing the insulation or opening the kettle.

If you do add heat, just keep it very gentle, and stir constantly (be patient, the temp will rise slowly). If you do that you won't scorch your bag.

 

[DaveCS]

I’m doing small batch BIAB (1 gallon) so, for me, the mash temp seems to maintain pretty well in the kettle since I’m using a no sparge method (i.e. all my water is in the kettle with the grain). I just put the lid on and, if necessary, put the kettle in the stove to hold the temperature.

I did a brew on the weekend and left my kettle on the stove...my temp dropped from about 155 F down to 147F over the whole hour... and that included opening the lid, stirring a bit, measuring the temp etc.

Cheers,
Dave

 

[Morrey]

I use propane burners for both 10G and 20G kettles for BIAB. I have found, similar to Mongoose33, that temperature layers form making it difficult to get an accurate reading unless you stir hard. Then, by stirring hard, you are cooling the wort. Heating with the burner is tricky and difficult to hit it just right w/o overshooting.

I use two insulating items compliments of a moving company. I use a quilted, padded movers pad thrown over the kettle followed by a heavy movers blanket on top of that. These insulators will maintain my mash temps on a typical brew day around 1 degree for an hour or even a 75 minute mash...maybe two degrees at the most but never more than that. Just play around with your strike temp anticipating a temp drop while doughing in, then insulate well.

 

[soccerdad]

Just my experience, but I find it easier to hold temp indoors with stovetop BIAB than outdoors with a larger batch

 

[wilserbrewer]

Similar to cooking anything with a thick consistency, say spaghetti sauce for example. If you add heat it is best to use low heat and stir constantly. Without constant stirring the heat is not dissipated from the bottom of the kettle and temps soar and can scorch.

If you use a little care, gentle heat and stir, you don’t need a clad bottom pot, or a false bottom imo.

Gentle heat and stirring is the key...if the heats on you should be stirring, it’s that simple.

 

[wilserbrewer]

The worst possible combination is someone tries to heat up to mashout temps without stirring, equals burnt mess

 

[Browne]

Greetings Fellow Brewers,
I'll be doing my first BIAB all grain in a couple of weeks and after reviewing a lot of threads and videos it looks like most of you insulate (in a variety of methods) to keep your mash temps close to desired state. However I've seen a few folks simply measure the temp occasionally and turn on their burners for a short period of time to get the mash temp back up. Does anyone know if using the burner option has any undesired side effects other than the hassle?

I heat with propane. Remove kettle and sit it on heavy blanket; wrap kettle in sleeping bag. Stir twice, every 20 min. Might lose 3-4C degrees in an hour in -10C temp ~15F.

 

[deadwolfbones]

I use my Anova sous vide wand (outside the bag). Works great for the 3 and 5gal batches I'm doing, and also helps recirc.

 

[RM-MN]

You need to hold mash temps only until the conversion is complete. That might be 60 minutes, or 90, or 120, or maybe only 5 minutes. It all depends on the quality of the crush with fine crush being really quick. If your conversion takes more than 60 minutes, find somewhere else to get your grains crushed or get your own mill.

I'll usually only leave my grains in the wort for 30 minutes, not because it takes that long to convert, but that seems to be the sweet spot between taking more of my time and getting all the color and flavors extracted from the grains. Even if the conversion is done in 10 minutes, don't stop there as you don't get the flavors.

 

[DaveCS]

You need to hold mash temps only until the conversion is complete. That might be 60 minutes, or 90, or 120, or maybe only 5 minutes. It all depends on the quality of the crush with fine crush being really quick. If your conversion takes more than 60 minutes, find somewhere else to get your grains crushed or get your own mill.

I'll usually only leave my grains in the wort for 30 minutes, not because it takes that long to convert, but that seems to be the sweet spot between taking more of my time and getting all the color and flavors extracted from the grains. Even if the conversion is done in 10 minutes, don't stop there as you don't get the flavors.

This is a good point! A finer crush, meaning a “faster” conversion (I use the quotes because the word is relative to each individual’s brewing set up), would/could also suggest that one may not need heat their strike water too far beyond their targeted mash temperature.

For example; I aimed for 160F in my last brew (about 10F above the mash temp I wanted) for strike temperature and dumped in my grains expecting it to drop significantly but I had adjusted my grain crush to be a lot finer and I had more water in the kettle than required based on my brewing set up (still dialing that in).... so the temperature didn’t drop as expected immediately and I ended up mashing at a higher temp than I wanted to.

So one could end up saving time and energy if they know how the crush impacts their conversion ability.

Thanks RM-MN!

Cheers,
Dave

 

[Morrey]

This is a good point! A finer crush, meaning a “faster” conversion (I use the quotes because the word is relative to each individual’s brewing set up), would/could also suggest that one may not need heat their strike water too far beyond their targeted mash temperature.

For example; I aimed for 160F in my last brew (about 10F above the mash temp I wanted) for strike temperature and dumped in my grains expecting it to drop significantly but I had adjusted my grain crush to be a lot finer and I had more water in the kettle than required based on my brewing set up (still dialing that in).... so the temperature didn’t drop as expected immediately and I ended up mashing at a higher temp than I wanted to.

So one could end up saving time and energy if they know how the crush impacts their conversion ability.

Thanks RM-MN!

Cheers,
Dave

Getting that "perfect" strike temperature is part of getting to know your individual set-up as you mentioned. In most cases, I overshoot strike water temps by 4 - 5F, then after adding the grains, I will drop right down to my ideal mash temp. Some folks call this "Kentucky Windage"...lol.