Installing a weldless thermometer

These pictures show the front and sideview of one of Blichmann Engineering’s BrewMometer (TM) Stainless Bi-Metal Thermometer that I installed today on one of my keggles.

Blichmann Engineering's BrewMometer (TM) Stainless Bi-Metal Thermometer

To install it, I drilled a 3/16-inch pilot hole and then enlarged it to 1/2-inch with a step drill. The instructions don’t say it but it’s a good idea to use “cutting oil” to cool the bits and the metal you drill through. (A shout out to Daniel of Two Dudes Brew for loaning me the step drill bit and recommending the use of cutting oil. Good call!) I used 3-in-1 oil and it worked well. I stopped drilling anytime smoke started, reapplied cutting oil, and waited a minute to allow the bit and metal to cool. The step drill bit left a nicely chamfered hole free of sharp burs.

Side view of Blichmann Engineering's BrewMometer (TM) Stainless Bi-Metal Thermometer (Note the stainless washer on the outside)

After installation, it looked great on the keggle, but it leaked. After checking some chatroom threads, I found that fixing the problem required two metal washers–one on the outside (which the instructions call for) and one on the inside (which isn’t called for by Blichmann’s instructions, nor provided). The o-ring went on the outside within the stainless washer. The two washers, one inside and one outside, stopped the leak.

Now, I hope I haven’t installed it too close to the bottom. According to the instructions, “A minimum distance of 6″ from the bottom of the pot is recommended, but does not guarantee it will be below 140F.” We drilled the hole 7 inches from the bottom to stay off the rib of the keggle. However doing that puts the bottom of the dial face only 5 inches from the bottom of the pot. A heat shield may be in order. I plan to place the keggle so that flames don’t climb the side of the thermometer.

A piece of metal is placed below the thermometer to shield it from convective heat.

I found that a heat shield was needed. I put a piece of stainless steel under the keggle. That worked for awhile but, after 10-20 minutes it got hot to the touch and I crumpled  aluminum foil and wedged that just under the thermometer and that brought the convective/radiant heat hitting the bottom and face of the thermometer to almost nothing.

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This week on Brew Disasters: Laurel India pale ale


English: Malted Barley, more specifically a &q...

Milled malted barley before it is mashed into heated water. (From Wikipedia Commons)

This week on Brew Masters Disasters: Julian Shrago’s Laurel India pale ale.

Well, there’s trouble in Laurel Land. We really screwed the mash temperature and may have to throw the whole batch down the drain. Tens of dollars could be lost.

Mash, as you know, is the result of combining hot water and milled barley grain to make a grain soup that resembles oatmeal.

According to Wikipedia, mashing is the process of combining a mix of milled grain (typically malted barley with supplementary grains)… and [heated] water. Mashing allows the enzymes in the malt to break down the starch in the grain into sugars, typically maltose to create a malty liquid called wort.

Depending on the temperature, certain enzymes will be activated which will break down starches into sugars. The higher the temperate, the greater the non-fermentable sugars (top end 156), which will give the beer a sweeter taste with more mouthfeel. The  lower range releases more fermentable sugars for a drier taste (low end 148). There are temperatures that are  too low which will not activate any enzymes. There are temperatures that are too high that will denature enzymes.

My desired mash temperature was 151°F. I heated my water to 161°F. My expectation was that when I added the grain to the hundred and 61°F water it would drop about 10°F and give me my desired mashing temperature of 151°F. Instead, it dropped to 144°F when I added my grain. To low. Since I mash in converted cakes I decided to try slowly heating the mash to reach 1 51°F. I used a very low flame and monitored the change in temperature every 3 min.

I use a Taylor 9842 Commercial Waterproof Digital Thermometer to get my readings by poking it into the porridge-like mixture. I checked it didn’t seem to be raising much and in fact the temperature would peak and then begin to drop on my digital thermometer. I set my timer for another three minutes and checked my mash temperature after the timer went off. Well, lo and behold, my mash was now at 175°F, high enough to denature the grain’s enzymes. Oh crap! I added some cool water and brought it down a little not below 171°F. I added a little more cool water and finally I was able to get it down to 151°F. Then, the mash rested for an hour.

I continued on because as Charlie Papazian advises, “Relax, don’t worry, have a homebrew.”

I did a 90 minute boil and added hops according to the recipe, and pitched the yeast at 3:30pm. Fermentation had started by 5:30pm. I have my fingers crossed that it is good yeast-caused fermentation and not from lactobacillus or pediococcus.

Here is Julian Shrago‘s of Beachwood Brewing‘s recipe:

– 5 gallon batch at 75% efficiency –

* 11.5 lbs. American 2-row malt
* 0.4 lbs. Carapils malt
* 0.3 lbs. Crystal 40 malt

Mash @ 151 degrees Fahrenheit for one hour.

90 minute boil

* 0.8 oz. Amarillo pellets (9.6% AA) for first wort hop (FWH)
* 0.55 oz. Summit pellets (18% AA) for 60 minutes
* 0.75 oz. Centennial pellets (9.2% AA) for 30 minutes
* 0.3 oz. each Simcoe (12.2) and Columbus pellets (14.0) for 10 minutes
* 0.5 oz. Amarillo pellets (9.6% AA) at flameout/whirlpool
* Dry hops: 1.3oz each Amarillo, Centennial, and Summit pellets for two weeks

Ferment with White Labs California Ale Yeast WLP001 or Wyeast 1056

OG/FG: 1.064/1.010
SRM: 5.2
IBUs: 108

Note: I subbed Zythos hops for the amarillo hops.