Mixed readings with Thermapen Mk. 4

[wahoowad]

I have a new Thermapen Mk. 4 and have had some odd usage out of it, and today I decided to be very focused on the readings it produced. I have some beef ribs that were close to ready so I checked them with the ThermaPen.

I keep getting different results that vary by a significant amount. It doesn't make sense to me. Sometimes the temp is where I would expect, sometimes it is 20+ degrees off. I know these beef ribs are about done given they are probe tender but I am also getting readings of 170 and 180 and it just seems random.

I don't want to doubt the device as it is one of the highest quality tools I have in my smoking/grilling toolbox, maybe someone will just clue me in on what I am doing wrong? I feel the probe is going to almost same spots in the meat and should be fairly close but it isn't.

 

[dr k]

If you stick the probe in boiling water and it is correct at your elevation and 32*f in a properly made ice bath, then it's a temp of the bone, near bone, fat or meat away from the bone.

 

[kruizer]

^^^^what he said^^^

 

[johnmeyer]

The Thermapen sensor is really, really tiny and is located in the sharp tip at the end of the probe. One of the beautiful things about it is that you can get very local temperatures. As a result of that feature you are finding something that most people never know, namely that the temperature of your food while cooking is not even remotely close to being uniform.

The "resting" period after cooking is important for all sorts of things, like retaining juices, but it also helps the cooking even out. With a big roast, the outside is often 180 degrees, and the interior only 135. Letting it rests causes the interior to get heated from the energy in the outside of the roast, hence the somewhat misleading, but still useful idea that the roast continues to cook after you take it out of the oven.

If you really want to see this heating disparity even more clearly, use the worst heating sources for getting uniform cooking: your microwave oven. I used to re-heat lasagna in the microwave and then insert the Thermapen probe in various places. I often measured 160 degrees near the edges, and 100 degrees near the center ("microwave ovens cook from the inside out" is a complete and total fiction -- couldn't be more wrong).

So, I think what you are seeing is normal, as others have already said.