Is using a sous-vide to get to strike temp, then not regulating mash temp a viable approach?

[Yirg]

If the old experiment by brulosophy.com is representative and mash temp is indeed not that critical, I think it can make a sous-vide a tool that really simplifies mashing. Here's what I have in mind:

1. Get strike temperature where it needs to be by using a sous-vide to heat water directly in the pot, without using a dedicated mash tun
2. Once water temp is reached, take the sous-vide out, put the grain in.
3. Cover the pot and let mashing continue without worrying about temperature and without trying to prevent it from dropping.

Would this really result in beer that's indistinguishable (to most people) from one that was brewed with tightly temperature-regulated mashing? If so, it could reduce the bar for all-grain home brewing and make it not that much more demanding than using partial mash or extract + specialty grains.

 

[RM-MN]

Two thoughts.
1. How finely your grain is milled determines the time it takes to get full conversion. A very poorly milled grain may take more than 2 hours to complete in which case the temperature drop would put that final amount of time outside the conversion temperature range. That would make an already poor mash efficiency even worse.
2. The results of number 1 would matter as to whether or not a average person could tell the difference. It also would matter the reason a person is drinking the home brew. Some people drink because they like the taste and don't much care if they get a buzz from it. Some people want to drink their home brewed beer to get drunk. For the latter, a really poor mash efficiency would result in a much lower alcohol by volume and make getting drunk much more difficult.

 

[Yirg]

Thanks for raising these points. I have my own grain mill and can control how fine it grinds.

As for getting drunk, that's not a goal, so no issue there. I only care about the beer tasting good. I do want efficiency to be good, but the lower temperature may actually be beneficial here. To quote from the article I linked in the OP:

The low mash temp beer had a calculated 4.4% ABV while the high mash temp beer clocked in at a much lower 3.4% ABV.

 

[GrowleyMonster]

If the old experiment by brulosophy.com is representative and mash temp is indeed not that critical, I think it can make a sous-vide a tool that really simplifies mashing. Here's what I have in mind:

1. Get strike temperature where it needs to be by using a sous-vide to heat water directly in the pot, without using a dedicated mash tun
2. Once water temp is reached, take the sous-vide out, put the grain in.
3. Cover the pot and let mashing continue without worrying about temperature and without trying to prevent it from dropping.

Would this really result in beer that's indistinguishable (to most people) from one that was brewed with tightly temperature-regulated mashing? If so, it could reduce the bar for all-grain home brewing and make it not that much more demanding than using partial mash or extract + specialty grains.

You might need two sous vide wands for heating enough strike water for a 5 gallon batch. Even so, it is gonna be like watching paint dry. But you could probably set both to your desired mash temp and leave them in, or leave one in. I have been thinking about trying that, myself, since my first adventures in sous vide cooking.

 

[micraftbeer]

I currently brew with a RIMS setup, so constantly recirculating, and frequently doing step mashes of some sort. But before that, I brewed on propane outside and did essentially as you describe. I didn't use a sous vide, but once I hit strike temperature, I mashed in, and was done for an hour. I used an old winter coat to sit around my mash tun to hold the heat. I'd last a 60-minute mash with only losing 1-2 degrees. So definitely possible to get good performance.

I'm guessing the sous vide part comes in so you can set it long before brew start and it will get to temp and hold it until you're ready. That seems reasonable.

I switched to RIMS because sometimes I didn't hit my strike water exactly and it was a pain to adjust. Sous vide would eliminate that. I also like RIMS for my step mashes. Sous vide would be too underpowered probably to try that.

 

[RM-MN]

You might need two sous vide wands for heating enough strike water for a 5 gallon batch. Even so, it is gonna be like watching paint dry. But you could probably set both to your desired mash temp and leave them in, or leave one in. I have been thinking about trying that, myself, since my first adventures in sous vide cooking.

I've seen some report that they put the sous vide into the water in the evening so the water is up to strike temp for a morning brew. Quicker would be to start heating on a burner and then switch to the sous vide to get to the strike temp without needing to be watching so closely.

 

[Yirg]

I've seen some report that they put the sous vide into the water in the evening so the water is up to strike temp for a morning brew. Quicker would be to start heating on a burner and then switch to the sous vide to get to the strike temp without needing to be watching so closely.

That's exactly what I plan to do and one of the reasons why I'd like to to use a pot for mashing and not a separate mash tun.

I switched to RIMS because sometimes I didn't hit my strike water exactly and it was a pain to adjust. Sous vide would eliminate that. I also like RIMS for my step mashes. Sous vide would be too underpowered probably to try that.

I'm brewing indoors, so there's less chance of things like wind affecting mash temperature. I also don't plan to step mash (brulosophy.com to blame here too ), so RIMS setup is the opposite direction from what I'd like to achieve - simplify the mash process, have less things to worry about, reduce the amount of gear that needs to be cleaned, keep costs to the minimum - and all that, without impacting beer quality.

 

[marc1]

The method that you heat your water isn't going to make a difference to the beer. (Barring something silly that contaminates the water).

If you had heated your water in an HLT by any method, and then added to your grain, you'd have the same result, no?

 

[hotbeer]

I'd just heat the water up with something that cost less than my sous-vide. Why wear it out trying to get cold water to strike temp? But some sous-vide's are about the price of a decent burner. But which will last longer? Which will heat it up before you get tired of messing around?

 

[Yirg]

The method that you heat your water isn't going to make a difference to the beer. (Barring something silly that contaminates the water).

If you had heated your water in an HLT by any method, and then added to your grain, you'd have the same result, no?

Sure, but what I'm suggesting here is all about convenience (without compromising quality). Press a button, wait for the water to reach exact strike temperature, put the grains in and come back when the mash is done.

Furthermore, you can (sort of) avoid the waiting by scheduling the sous-vide to the next morning, so that when you wake up on brew day the water is already at the correct temperature. Convenience and simplicity are worth $70 I think.

 

[CascadesBrewer]

Would this really result in beer that's indistinguishable (to most people) from one that was brewed with tightly temperature-regulated mashing? If so, it could reduce the bar for all-grain home brewing and make it not that much more demanding than using partial mash or extract + specialty grains.

It would be interesting to see some research into the impact of falling mash temps. I do BIAB and crush my grains fairly fine. With my 5 gallon batches wrapped in a sleeping bag, I measure a 1F to 2F drop over a 60 minute mash. I do a number of 2.5 gallon batches. With those I often measure a drop in temps of 4F to 6F over 60 minutes. Maybe I could try to analyze data from my batches, but if I mash in a 152F and the temp drops to 146F over an hour, the results seem very close to what I would expect for a constant 152F mash.

But in general, what you are talking about seems in line with what many brewers have done. The guys mashing in coolers don't have an easy way to add heat during the mash. With my BIAB setup and propane burner, adding heat during the mash is more likely to cause issues than fix problems. I am not sure that most sous-vide units are really designed to heat up the near 8 gallons of strike water that I would typically use in a 5 gallon batch though.

 

[marc1]

Sure, but what I'm suggesting here is all about convenience (without compromising quality). Press a button, wait for the water to reach exact strike temperature, put the grains in and come back when the mash is done.

Furthermore, you can (sort of) avoid the waiting by scheduling the sous-vide to the next morning, so that when you wake up on brew day the water is already at the correct temperature. Convenience and simplicity are worth $70 I think.

Exactly, so as long as you're OK with a temp drop (will be system dependent) you're fine. BIAB people do something like this all the time. Wrapping the kettle in insulation (reflectix, sleeping bag, coat, etc.) helps keep it from dropping too much.

You can certainly dial it in over a few batches, so that your average temp is in the area you want it to be.

Like most process changes you have to try it out to see how it works in your hands, maybe tweak it to get it performing well for you.

Have you done a single infusion mash before without actively heating it?

 

[RM-MN]

With my 5 gallon batches wrapped in a sleeping bag, I measure a 1F to 2F drop over a 60 minute mash. I do a number of 2.5 gallon batches. With those I often measure a drop in temps of 4F to 6F over 60 minutes. Maybe I could try to analyze data from my batches, but if I mash in a 152F and the temp drops to 146F over an hour, the results seem very close to what I would expect for a constant 152F mash.

First analyze how long it takes for full conversion. Once full conversion has occurred the temperature drop doesn't change it. You may have a constant 152 degree mash during conversion but until you analyze when that has occurred you won't know.

 

[CascadesBrewer]

First analyze how long it takes for full conversion.

I am not exactly sure how I would test for "full conversion". I am not convinced an iodine test will tell me that no more break down of sugars will occur. I could try taking multiple refractometer readings to monitor gravity changes. For me a 60 minute mash gives me a good window to calibrate my pH meter and take a reading, to prep other ingredients/equipment, and often to eat breakfast. I crush my grains pretty fine, so I expect conversion is done fairly quickly.

 

[RM-MN]

I am not exactly sure how I would test for "full conversion". I am not convinced an iodine test will tell me that no more break down of sugars will occur. I could try taking multiple refractometer readings to monitor gravity changes. For me a 60 minute mash gives me a good window to calibrate my pH meter and take a reading, to prep other ingredients/equipment, and often to eat breakfast. I crush my grains pretty fine, so I expect conversion is done fairly quickly.

You'll probably need to do several test batches where you use the same ingredients in the same proportions and change the mash period for each, then check the FG to see if you get a more fermentable wort by mashing longer. In my case the difference between a really short mash and longer ones was in the flavor extracted. The FG stayed the same. The very short mash resulted in beer with the same alcohol level of the longer mashes but had little flavor.

Try the iodine test first, then the varying mash period to see if the FG changes for you.

 

[CascadesBrewer]

If the old experiment by brulosophy.com is representative and mash temp is indeed not that critical, I think it can make a sous-vide a tool that really simplifies mashing.

Cycling back to the original post...

I am in the "mash temp is not that critical" camp, but I do feel that mash temp is important. Mash temp does have a direct and noticeable impact on the fermentability of the wort. OG and Mash Temp are important levers that can help you drive the character of a beer along with the final ABV.

While I feel feel that the "low mash = thin/dry, high mash = thick/sweet" rule is mostly bogus, I to tend to think that a low mash temperature beer that is more fermentable produces a more "digestible" beer. So even if tasters cannot pick out the difference between a 147F and a 161F mash temp beer when drinking a small sample, I tend to think that the difference would stand out more after drinking a pint of each beer. I do target different mash temperatures for different styles, though I could probably mash every beer at 152F without a lot of impact.

So is "tightly temperature-regulated mashing" important? Is the mash temperature at 0 min to 15 min (or 30 min?) the driver of the character of the mash? Does it matter if your mash drops 2F vs 4F vs 8F over 60 minutes? My mostly anecdotal experience with minimal data to back it up, says that a drop of 5F over an hour has minimal impact. I am not sure how this applies to other systems, ingredients or grain crush. There is a part of me that wants to limit the drop to around 4F just for consistency. I am not sure I would be comfortable with a 10F+ temp drop.