DIY add on for HERMS Brewing Rig

Here's a tale of wort aeration/oxygenation and HERMS build for you. I first started brewing beer using canned syrup in tin cans. It seemed to me that every beer made tasted like metal. So I decided to read and read some more on the subject. I tried all grain mash on my kitchen stove and loved it. Now I'm aiming sky high with an all electric HERMS setup. After hitting the wall of the cost of stainless steel. I decided to go on a long term project with all the DIY I could make. I first made the return arm/sparge arm for my mash tun. John J. Palmer, How to brew book helped me on the mistakes that can be made while returning the mash on the grain bed. I'm referring here to hot side aeration. When you mash is hot. It is best to avoid splashing and bubbling air in it. Some enzymes like lipoxygenase will link oxygen to compound in the mash. You actually don't aerate you wort you're oxidizing it. I so decided to make a multiple concentric circular tube to return the wort just below the surface in the grain bed.

The idea was simple but the 5/8 copper tubing bending was not. After a couple hours of work the height adjustable concentric return arm was born! With this design I hope to get an even distribution of the liquid over the grain bed. This picture shows the unfinished version. The vertical copper pipe was a short one to allow soldering correctly the tee to the copper ring. It was replaced with a longer one that could reach the smallest grain bill down a Sanke keg. A silicone tubing was attached to the 5/8 Stainless steel barb on top to raise or lower the arm. The other end of the silicone tubing is connected to another 5/8 barb to NPT fitting in a welded coupling. A male camlock connection is sticking out of the top side of the keg. This is where I connect the tubing returning from the HERMS coil.
Now for the in hot liquor tank. A small but essential detail is the even distribution of heat in the water. To be able to strike a given temperature for the HERMS coil I decided to go with the good old lab stirrer. All from stainless steel again. It made a perfect couple with this old angle drill. This drill is sitting on the cover of the HLT. The propeller is quite small but moves a lot of water. It improves the heat exchange with the copper coil and my temperature probe can be placed anywhere in the tank.

My second creation was the sight glass oxygenation tube. I decided to figure out how to trap a Pyrex tube between stainless steel. It seems easy at first. It took more than a month to get my final idea to life. Heavy wall large ID Pyrex tubes are not easy to find for the use of home brewing. In the other hand guitar players do know what a Dunlop tube is made of. This find was the center piece of my built. I've used two inch NPT stainless steel flanges. I found online the perfect high temperature silicone gasket. The two flanges were held in place by 5/8 inch threaded rods with bolts. Yeah it looks like an overkill and it is! On one side the cold wort comes in. A 2 micron stainless steel aeration stone is hanging right in the center of the glass tube. This allows you to see if your stone is working properly. With a small ID tube it forces wort to get in contact with the air/oxygen coming out of the stone. On the opposite side you have a thermometer and the output to the fermenter.

God I love home brewing. What is great in building your brewing rig is the choice and freedom you have. With knowledge, creativity and passion every malty drink is possible.

 

[CarbonTom]

Wow!! That sight glass/aeration port is so awesome! Do you have a detailed post on your build? Pics or a video of it in action? I am building an eHERMS and would love to include one of these in there. Ingenious

 

[ScrewyBrewer]

Interesting article and a great job with the HERMS add on design, thanks for sharing. To some folks the name hot side aeration would kind of say it all, even if it were called hot side oxidation. IMHO either way the extent of any adverse impact it would have on the finished beer would still be subject to intense debate. As with any DIY project at the end of the day if it gives you better tasting beer it's definitely worth doing.

 

[Oshodisa]

The aeration tube looks really neat & along the lines of something I've been chewing over in my mind.
Would you be so kind as to post a full parts list & as mentioned above an idea of how to put it together.
Cheers

 

[RBGilbert2]

According to Palmer's book (p 145 or How the Mash Works, Doughing-In for the online version), lipooxygenase is denatured at 140F. I would think that as long as you do a non-aerating dough-in, hot side aeration should not be an issue at mash temperatures. I use a HERMS system with a similar setup but do keep the sparge/recirc arm slightly above the liquid level and have never noticed off-flavors that I'd attribute to oxidation.

 

[Humuleneman]

@Oshodisa, Sorry for the delay to answer back, here's the part list for my sight tube. it starts with: Jim Dunlop 213 Dun Btlnk Slide Hvy Large from amazon and 2 x Silicone Flange Gasket, Ring, Red, Fits Class 150 Flange, 1/8" Thick, 1/2" Pipe Size, 27/32" ID, 1-7/8" OD (Pack of 1), also from amazon. the 2 stainless flange were ordered at my local plumbing shop. they are 3/4 inch pipe thread flanges.you can take a look at http://www.hsflanges.com/ANSI_ASME_ASA_flanges_Threaded.html#.VMh1av5JkrU. those are pretty much the same. The threaded rods are 5/8 standard with some nylon bolts on the inside and ordinary nuts on the outside. the hardest part was to measure the correct spacing between the two flanges. i've used a vernier caliper to be sure that all inside nuts were exactly spaced equally and that they aren't to close to crush the pyrex tube and not to far apart to give leaks .The fitting on the outside of the flanges are up to you. i've use probe compression fitting from brewhardware on each side to hold the aeration wand and the thermometer. with some tee's you can use barb, camlock or triclover connection for you hoses.
thanks again