Cooling mash before pitching (on grain fermenting)

[Stump Lake]

20260828_141206.jpg

Here is a picture of my cooling coil with the aerator You can see the air stone attached to the the bottom of the cooling coil. You can also see the air pump that I use to drive it with.

This rig has greatly increased the efficiency of the cooling coil. I use it to cool down a 55 gallon blue barrel of mash just before pitching my yeast. The air rising up past the cooling coil moves the mash around the coils cooling it down much faster.

I don't have to stir the mash. The air rising from the air stone continuously stirs the mash for me. It cools so much faster than when I used a cooling coil without Agitation. I don't use a paddle or a drill to stir my mash. It's a perfect lazy mans mash day.

A whiskey mash needs oxygen in the very beginning right when you add the yeast. The moving air stirs my mash moving it past the coils of my cooling coil and adds oxygen to my mash for a good yeast start.

[Osse87]

The few times I've done AG batches, I've mashed really thick, then you can add more cold water when diluting. Mash as thick as you can handle, enzymes/conversion loves it aswell IME.

[The Booze Pipe]

20260828_141206.jpg

Here is a picture of my cooling coil with the aerator You can see the air stone attached to the the bottom of the cooling coil. You can also see the air pump that I use to drive it with.

This rig has greatly increased the efficiency of the cooling coil. I use it to cool down a 55 gallon blue barrel of mash just before pitching my yeast. The air rising up past the cooling coil moves the mash around the coils cooling it down much faster.

I don't have to stir the mash. The air rising from the air stone continuously stirs the mash for me. It cools so much faster than when I used a cooling coil without Agitation. I don't use a paddle or a drill to stir my mash. It's a perfect lazy mans mash day.

A whiskey mash needs oxygen in the very beginning right when you add the yeast. The moving air stirs my mash moving it past the coils of my cooling coil and adds oxygen to my mash for a good yeast start.

I have a shop size air compressor next to my mashtun. I'll have to look to see if I can run one of these air stones from my compressor. I'm getting tapped out on space for any more tools and stuff

[Stump Lake]

I have a shop size air compressor next to my mashtun. I'll have to look to see if I can run one of these air stones from my compressor.

A shop compressor should be way more than adequate. You'll probably have to dial back the pressure some.

I made mine up from parts I had laying around.

[PalCabral]

That’s a great idea, Stump. I will try this later this week!

[higgins]

There is a chance of some oil droplets getting thru a compressor. I'd use an inline filter to ensure that doesn't happen.

[Stump Lake]

There is a chance of some oil droplets getting thru a compressor. I'd use an inline filter to ensure that doesn't happen.

That is a good idea

[shadylane]

Maybe use a small oil less compressor. Something cheap meant for running an airbrush.

[The Booze Pipe]

Maybe use a small oil less compressor. Something cheap meant for running an airbrush.

I should be able to adapt this to a type C air fitting.
https://pondscape.com/products/easypro- ... 5603597624
The compressor I have now is oil-less. But maybe I should still add a catch or filter? I can turn my regulator way back to 10psi

[shadylane]

Here's a thought for injecting air into the fermenter that would stir things up.
Make a big cap with slots and put it on the end of a pipe.
This way the injector can sit on the bottom without plugging up, it would also be easy to clean.

[Stump Lake]

Here's a thought for injecting air into the fermenter that would stir things up.
Make a big cap with slots and put it on the end of a pipe.
This way the injector can sit on the bottom without plugging up, it would also be easy to clean.

That should work.
When I first started using this method I was just using the airstone to add oxygen (air) to my mash before pitching my yeast. I was using the cooling coil as a stand alone. When I dropped the airstone into the mash, it was like Wow, that really got the mash moving.

I started sticking the airstone around the cooling coil to get the mash moving past it. That worked so good I eventually tied the airstone to the cooling coil.

[shadylane]

Using air to kill two birds with one stone. If Ya want to cool something off, blow on it and stir.
I use a drill powered stirrer on a timer. A couple seconds on until the mash is a tornado and the prop cavitates then several minutes off.

[The Booze Pipe]

Here's a thought for injecting air into the fermenter that would stir things up.
Make a big cap with slots and put it on the end of a pipe.
This way the injector can sit on the bottom without plugging up, it would also be easy to clean.

I like that idea. But with what material? I would use copper but it would be expensive! a two or three inch cap, reducers, adapter, npt this & that. I could silicone hose straight to a cap (if it was heavy enough).

[shadylane]

I like that idea. But with what material? I would use copper but it would be expensive! a two or three inch cap, reducers, adapter, npt this & that. I could silicone hose straight to a cap (if it was heavy enough).

1/2" copper tubing for the pipe and some sheet that's been rolled into a cap.
Add around $1 worth of solder and torch gas.

I'd have air injector in the middle and the chiller wrapped around it.

[Stump Lake]

I'd have air injector in the middle and the chiller wrapped around it.

yea Shady putting the air injector in the center of the cooling coil would work better. When I built mine I just threw it together. POC (PROOF OF CONCEPT) kind of thing. I had the cooling coil, and I had the air injector, and I had some cables ties. BOOM it was all tied together. I sunk it in my mash and "Da.n that actually worked"

Having the air injector centrally located at the bottom of the cooling coil would work the mash more evenly around the cooling coil for better heat transfer.

[higgins]

Injecting air into wort/mash for oxygenation is great, but in the beer world brewers are cautioned not to expose hot wort to aeration.

This is called HSA, or Hot Side Aeration. Oxygen binds to the malt and creates trans-2-nonenal and causes beer to develop that wet cardboard character, but it takes a few months to develop.

This may not be applicable to mashing for distillation, but may be something to consider.

[Username]

Injecting air into wort/mash for oxygenation is great, but in the beer world brewers are cautioned not to expose hot wort to aeration.

This is called HSA, or Hot Side Aeration. Oxygen binds to the malt and creates trans-2-nonenal and causes beer to develop that wet cardboard character, but it takes a few months to develop.

This may not be applicable to mashing for distillation, but may be something to consider.

The idea of hot side aeration has been discounted by the brewing industry in recent years.

Many modern brewhouses are now designed to allow for vigorous pumping of the hot wort over spreaders to help volatilize SMM (DMS pre courser) in the boil kettle during "DMS breaks"

[Stump Lake]

Injecting air into wort/mash for oxygenation is great, but in the beer world brewers are cautioned not to expose hot wort to aeration.

That was new to me so i had to look it up. Its is a thing It seems to be hottley contested like most things in our hobby. Some brewers claiming not to Inject over 80F.

also found this

injecting air into hot wort modern consciousness temperature below 120

Injecting air into hot wort (above 140°F / 60°C) causes hot-side aeration (HSA), which leads to staling, cardboard-like flavors, and poor shelf life in beer. In modern brewing science, oxygenating wort is perfectly safe and highly beneficial once the temperature drops below 120°F (49°C), with ideal aeration happening at pitching temperatures (60°F–75°F / 15°C–24°C).

While older homebrewing literature treated HSA as a catastrophic flaw, modern brewing consciousness recognizes it as a minor concern at the homebrew scale, but still a practice to avoid.

Why the 120°F (49°C) Threshold MattersChemical Stability: At temperatures above 140°F, oxygen rapidly binds to lipids and melanoidins in the wort. These chemically bound oxides don't scrub out during fermentation; instead, they slowly break down over weeks or months in the finished bottle or keg, creating trans-2-nonenal (the chemical responsible for wet cardboard or paper flavors).

The Safe Zone: As the wort cools below 120°F, the rate of these damaging oxidative chemical reactions drops drastically. While it is chemically "safe" from HSA at 120°F, you should still wait to inject oxygen until it is closer to yeast pitching temperatures. .

So I learned something. I haven't been Injecting air above 120 anyway.Just because I usually have a rest between 150ish and <120ish. Then from 120 to about 90ish I drop it fast with this method to pitch my yeast. Ive only used on 6 batches so far. I haven't noticed any off flavors yet.

[higgins]

TBH I haven't worried when aerating a bourbon mash below 100F.

[shadylane]

My take on HSA, or Hot Side Aeration is it's a beer brewing thing.
Beer needs to be quickly chilled from boiling, when chilling a mash the temp starts much lower.

[The Booze Pipe]

I would think HSA is a non-issue for us hobby distillers. I have no problems dropping my 50 gallon mash below 120f. But 110 down to 80 or less takes a long time.

[The Booze Pipe]

I like that idea. But with what material? I would use copper but it would be expensive! a two or three inch cap, reducers, adapter, npt this & that. I could silicone hose straight to a cap (if it was heavy enough).

1/2" copper tubing for the pipe and some sheet that's been rolled into a cap.
Add around $1 worth of solder and torch gas.

I'd have air injector in the middle and the chiller wrapped around it.

Again, I love the idea Shady. But I don't have much more than tin snips and an angle grinder on hand for that project. which makes it sound extra challenging it would be nice if it didn't look like Edward Scissor Hands made it

What exactly do you hold against a six inch or three inch air-stone? I could focus my efforts on a larger chiller, 1/2" soft copper coil that reaches the bottom of the mashtun, and tie the stone to it,

[shadylane]

What exactly do you hold against a six inch or three inch air-stone? I could focus my efforts on a larger chiller, 1/2" soft copper coil that reaches the bottom of the mashtun, and tie the stone to it,

I've got nothing against an air stone. Mostly I prefer to go the out of the box DIY route.

[Stump Lake]

On the issue of airstones vs. open air. I would think the smaller the bubbles are the better they are. Tiny bubbles rise slower than large bubbles. Also there is more surface area in tiny bubbles to transfer oxygen into the mash in tiny bubbles.

[The Booze Pipe]

What exactly do you hold against a six inch or three inch air-stone? I could focus my efforts on a larger chiller, 1/2" soft copper coil that reaches the bottom of the mashtun, and tie the stone to it,

I've got nothing against an air stone. Mostly I prefer to go the out of the box DIY route.

Overall I look to find a balance of "lab grade" and home made

On the issue of airstones vs. open air. I would think the smaller the bubbles are the better they are. Tiny bubbles rise slower than large bubbles. Also there is more surface area in tiny bubbles to transfer oxygen into the mash in tiny bubbles.

Good point on efficiency. Although the topic is cooling the mash, the secondary benefit would be adding O2 (I seem to not have any issue with this by using the stir paddle/drill motor). I assume the finer bubbles would have a greater cooling effect versus large air pockets.

[Stump Lake]

sorry I got off topic. i stand corrected.

[The Booze Pipe]

sorry I got off topic. i stand corrected.

I'm sorry Stump Lake, I didn't mean to make you stand. Maybe I didn't come across right, but I was just trying to stay on course. I liked your idea about efficiency/surface area with the smaller bubbles.

[Stump Lake]

It's all good. it's been an interesting topic so far. a lot of good information has been passed around.

[shadylane]

I assume the finer bubbles would have a greater cooling effect versus large air pockets.

Just guessing, so don't quote me.
I think finer bubbles from an air stone would aerate the mash better.
But bigger and more bubbles would stir the mash more and make the chiller more efficient.

[The Booze Pipe]

I assume the finer bubbles would have a greater cooling effect versus large air pockets.

Just guessing, so don't quote me.
I think finer bubbles from an air stone would aerate the mash better.
But bigger and more bubbles would stir the mash more and make the chiller more efficient.

Only one way to find out - some scientifical experiments