Fermenting in the Mash Tun

[Connor]

Anyone have any experience with doing this?

My idea is to get a steam jacketed mash tun then just leave the mash in the tank, pitch yeast, and ferment. The steam jacket could then be used with cold water to get down to pitching temperature and glycol to manage temperature during ferment.

I'm not worried about tying up the mash tun for a week or so while it ferments. We are not planning on doing more than one run every other week or so.

[Mash]

It's a way to start, but for a professional distillery it would be a tough go.

[Donutboy]

seems like you would be tying up an important piece of equipment. Keep your eyes open and I bet you could find a jacketed tank to use as an FV for less than you think. Nothing is impossible, it's all out there.

[Connor]

Yeah it would purely be just a way to start. Once we get rolling we definitely plan on getting dedicated pieces for fermentation. I'm just wondering if its possible, sounds like it though? I'm mostly worried about the steam jacket and if it could be doubled as a glycol jacket.

[OldSpye]

Not to be argumentative, but I've always been morbidly fascinated with this (recent) compulsion to minutely control fermentation temperatures.

I'm a traditionalist. For me, controlling the temperature in the fermentation room is enough - minute variation in the temperature of the wash as the yeast propagates yields taste profile differences that please me. Hence, we're going the completely open route, probably in wood.

[Jake Holshue]

Well we have something similar, but not exactly. Our reaction tank is a direct steam injection heated tank, with a glycol jacket so (when it is working properly, of which it is not currently) I can ferment in there and transfer to another tank after the weekend so I can start another batch on Tuesday.

Some thoughts on what your describing- So I worry about acidic condensate from your boiler steam contact with any residual glycol. Steam from a boiler is somewhat acidic and I can't recall the ph of glycol, and perhaps the effects wouldn't be instant, but I would be very hesitant about possible contamination of either your glycol, or your condensate tank back to your boilers. And it would seem cumbersome to rinse the jacket in between each heating/cooling cycle. Plus making sure you have proper pressure release valves on your jacket in case of catastrophic failure of your boiler(s)?

Maybe I am off base here, but it seems as though this may not be the best solution??

[Artisan Still Design]

you may find that if you do a grain in mash, that the grainsettleing on the bottom could become problematic. particularly if your mash tun is agitated from the bottom.

[Silk City Distillers]

For me, controlling the temperature in the fermentation room is enough - minute variation in the temperature of the wash as the yeast propagates yields taste profile differences that please me.

Controlling room temperatures requires a room, which may not be available, or cooling the entire production floor, which might not be a realistic option. From an energy efficiency perspective, it's going to require less energy to control the fermentation temp than it is going to be to control the room temp to indirectly control the fermentation temp. Also, depending on the fermentation volume and geometry, it might require an air temp lower than you expect. I've had ferment temps get into the 80s with an ambient temp in the 60s, so I can't imagine trying to cool a building down to the 60s when the outdoor temperature was in the high 90s. I don't have walls, and I sure as heck won't be paying to add air conditioning (jacketed fermenters look cheap in comparison).

[OldSpye]

Hey, Jim! Check your PM.

[mendodistilling]

If you can cool it down then you can use IBC totes made of plastic. The lid will allow co2 to blow off and then when you are done you can use hose and a forklift to gravity feed it into the pot still, then the preheater. The totes have a minor drain angle so it makes them a little easier to clean.

You can usually find them for under 100 used. I got some for 60 but they are all over the place.

You can also use macrobins. They are cheap. They come with lids or you can use a eurosealer for potato chips and painters plastic and make lids.

Using the mash tun for cooling becomes troublesome because of the glycol equipment you'll need to do it in a reasonable amount of time. You can also get a plate chiller from morebeer to use in the grape bin and a perforated racking wand to pull the beer/wine from the totes. All of it for under a grand and you can use a pump to move it all, not much work other than tipping the macro bins over and spraying them out.

[mendodistilling]

Ask the mfg'er if the equipment can handle the stress of the cooling too.