For some (myself included) holding a set temperature during the mash rest can be difficult. Many homebrew setups involve mashing in a cooler at a set temperature (Single Infusion Mash). In my experience getting this dialed in can be difficult and even with the best cooler there will be different temperatures throughout the mash tun itself. If you are like me, you also often times miss your initial target temperature when first mashing in and have to scramble by either stirring rapidly to chill or add quarts of boiling water to heat. For those trying to control mash temperatures over stove top it can be difficult as most kitchen stovetop elements really flucuate the temperatures of a liquid. Those with RIMS and HERMS systems are lucky and dont have said problems, they can disregard this whole post 🙂

Sous Vide is a popular cooking method based around cooking food in a vacuum sealed container that is then put inside a water bath thats heated to a precise temperature. I ended up with an extra Anova Sous Vide cooker and saw a post on the Anova site about using the SV cooker in a homebrew mash. Just recently I’ve started doing experimental 2.5 Gallon BIAB batches in my tiny kitchen and was excited to try this as I always had problems getting a precise temperature via my stove. The anova blog post didn’t get into much detail about using SV in a mash, so I figured I would make this post and go through my process & thoughts.

Setup

In the picture is a 5 gallon stainless steel pot with an insulation (reflectix) lining. As you can see in the picture above I have the SV cooker setup outside the mash bag. Since the lid wont fit due to the cooker I also have a reflectix cutout specifically to fit as a lid (see the right side of the picture).

Process

Fill your pot with your normal mash volume (the SV cooker doesnt take up much volume)

Set SV cooker to your target strike temperature. You can also turn on an element if you are on a stovetop, it will heat quicker this way. Make sure to turn off once you hit temp though.

Once strike temp is reached, mash in and set the SV temp to your target mash temperature.

Stirring occasionally is still recommended. The SV will circulate water, but its not strong enough to really circulate water fully through your whole mash. To ensure a consistent temperature, I think this is important.

Sometimes I do a mash out, this is easy to do with the SV as well just increase to your mash out temperature and wait.

After mashing out and trying to get up to boil temps, I usually crank up both my stove and SV cooker. This is helpful to get to boiling quickly. Once I start boiling I remove the Sous Vide and continue with my brew day

I’ve used my SV cooker for a fair number of batches now, and figured I would break down the pros and cons of using this tool in your mash.

Pros of SV Mashing

Trivial to set your target mash temp, and easy to maintain it.

If you want to do a step mash, this would be very easy to do as well.

Set it and forget it (for the most part, stirring occasionally is recommended).

Can function as a heat stick, and get you up to boil temperature quickly.

Cons of SV Mashing

Food Safety : Technically the SV is not a food safe cooking tool (when using a SV normally, the water bath is completely separate from the food being cooked). The SV could have grease/dirt in the internal parts, so I would recommend taking it apart and inspecting/cleaning it first. I’ve done a fair number of batches now with the Anova SV and havent died, so from my personal experience its food safe 🙂

: Technically the SV is not a food safe cooking tool (when using a SV normally, the water bath is completely separate from the food being cooked). The SV could have grease/dirt in the internal parts, so I would recommend taking it apart and inspecting/cleaning it first. I’ve done a fair number of batches now with the Anova SV and havent died, so from my personal experience its food safe 🙂 Cleanliness: While a BIAB mesh bag keeps most of grains separate from the SV, some small particles definetly get through and will start to accumulate inside the device. I’d recommend both double bagging and also regularily cleaning the SV. Here’s a shot of my SV after a brew. You can see all the grain matter that has accumulated. It’s getting very hard to completely clean it.

Damage to your SV: Since you arent cooking in a standard water bath, its possible your SV could break, either during the mash or when you take apart to clean. Some people have said the impeller (The part that circulates water) could break. So be warned.

Conclusion

Looking at both the pros and cons I ended up talking more about the cons. In truth I actually really like mashing with SV and think the pros outweigh the cons. For brewers who are very focused on cleanliness this might not be for them, because the SV could definetly introduce contaminants if not kept clean. Whether these contaminants will introduce either an infection or possible flavor changes, who’s to say. It’s certainly a risk. For me personally I love the convinence of SV mashing and am willing to deal with the risks.

For those that don’t want to risk contaminants or destroy their Sous Vide machines, you can find other uses in homebrewing. I’ll have a future post about doing a Lacto Sour with a SV, so stay tuned!