I have an accuracy issue with my Auber temperature sensor, and it goes something like this. I have a separate thermometer, and when the Auber is first on, the rwo agree within a degree. As the Auber probe remains in the pot however, the difference in measurements increase, until after some time, I see this.

Pot equilibrated to a measurement of 144, a few minutes after adding chicken. Note the temp difference between the two probes. Who to believe?

So who to believe? I’m concerned the Auber is underestimating temperature, because of the beef color of cuts like this, which was supposed to be cooked at 130 to 132 degrees F.

Nam Dae Mun ribeye, sous-vide and plated. Cooked perhaps 4 hours at Auber nomimal 130.

The above, sliced. Does that look medium rare to you?

So yes, I’m looking into how to accurately gauge and calibrate temperature with this setup. I’ve also been playing with higher temperatures, in part so I can cook chicken, which is a substantially smaller portion of meat than some of these big steaks I’ve been eating.

Jimmy (@EatItAtlanta) tweeted before my experiments that he wasn’t happy with the meat near the bone of chicken cooked at 140 F. Since I’m using a PID controller, and it overshoots temp by 2 degrees during the first couple hours, then the kinds of temperatures I’m looking at for my setpoint are 2 degrees below the cooking point. But if it’s actually running 3 degrees cool, I need to compensate by 5 degrees. Does that make sense?

PID controllers overshoot and then narrow in on their target temperatures. That first overshoot peak defines the actual cooking temperature for my controller. In practice, I overshoot by about 2 degrees F. Image above from Wikimedia, and the PID controller article on Wikipedia.

The French Culinary Institute’s PDF on sous-vide recommends 1-2 hours for chicken at 65-66C (149-151 F), and that means the two Auber temperature settings I needed to test are 144 F and 147 F. So we tested those.

Nam Dae Mun chicken thighs. Note the price.

Spiced and sealed. I used cracked black pepper, red pepper, crushed red pepper (pizza pepper), some onion and garlic powder, and a dusting of poultry seasoning.

Cooked 90 minutes at 144 from room temp and plated. 2.5 hrs at 147 from frozen has a similar appearance. I prefer the flavor and texture of the hotter product.

Results? I liked my chicken better at 147 than 144. The looks are about the same at both, and at both, you really do need to trim off the chicken fat, because unlike frying, the fat that results from this technique isn’t much fun to eat. The chicken is amazingly juicy, and you might find it not cooked enough for your tastes. If so, just keep ramping up the temperatures until you’re happy with what comes out of the controller.

As for me, I need a better way to calibrate my device. I would like to nail a good medium rare on the steak side. For now, I have a useful working temperature on the chicken side.

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