Wed
Nov 21 2012 10:00am

# The Late Mike Fellinger’s Turkey Algorithm: An Exercise in Geek Cooking

I still think of this as Jon Singer’s Turkey Algorithm, because that’s the title under which I knew it for decades; but Singer says it was devised by the late Mike Fellinger, and must be credited to him. It goes:

“For a turkey of greater than ten pounds, the roasting time should be equal to 1.65 times the natural log of the weight of the bird in pounds, cooked at 325 F.”

If you’re not a person who normally calculates natural logs, go to Google. Say you have a 20-pound turkey. Type in natural log 20 and hit the search button. Google will tell you that the natural log of 20 is 2.99573227. Multiply this by 1.65. The result will be 4.9429582455, or five hours.

And because there is no geekery without pilpul:

Ken Houghton’s Condensed Version: Just FYI, you can put the whole thing into Google. Typing in ln 20 * 1.65 (for a 20-pound turkey) yielded ln(20) * 1.65 = 4.94295825.

Erik V. Olson’s Cavil: I have to dissent from Mr. Singer’s algorithm, because we can do this vastly better emprically. The correct way to cook a turkey involves a probe thermometer inserted into the thickest part of the breast. Cook until 161F, remove, cover, let rest for 15 minutes, uncover, carve. ... Technology. It’s a lovely thing.

Henry Troup’s Expanded Principle: My best-cut algorithm is a 3/2 power law (which is a direct inversion of the square-cube principle). By my cooking log, Jon’s algorithm gives a bit longer time than I use. However, I cook at 350F, so the coefficient shifts.... I log every (big) bird I cook to refine the technique. The numbers in cookbook are a bit on the fuzzy side for my tastes. The same general algorithm can be used for things like pig roasts, too, just shift the curve to match the species and done-ness needed.

Brooks Moses’ Special Circumstance: If you have a small free-range turkey, your ideal cooking time may be considerably shorter than that yielded by the algorithm. Use a thermometer.

The Original Entry and Comment Thread: Making Light, 22 November 2007.

1.
Five hours is a good approximation of the time for a 20 lb bird at 325. I use a thermometer to get to 160 (as above) and your actual time will vary somewhat.
Resting the turkey, covered with a foil sheet, for 15 minutes after removal from the oven is key. If you cut right into it the juices will end up on the cutting surface instead of inside of you.
I should also note that you should only go up to 160 with a properly brined (wet or dry) bird. Otherwise, the water will be lost in any case.
2. Evan H.
This is just intellectual curiosity since I use a probe thermometer anyway, but... what if the bird's stuffed?
3.
Evan H.@2:The answer if you want to stuff the bird is to add a half hour onto the cooking time. Don't pack the stuffing in--loose is better.

The further answer is to just not stuff the bird--make a good dressing instead. The texture is more controllable and the chances of Venusian Slime Worms bacteria is greatly reduced.
4. sidhebaap
See also example 9, pages 26-28, in Partial Differential Equations, Sources and Solutions, by Arthur Snider. (Search inside at Am*zon for 'turkey'.)
5. Fashionablefoods.net
Its a pain to cook for so many hours..:(
6. Wordman
None of the above directions are correct for my tastes. For the best turkey, 4-5 days before you need it, call one of the restaurants in town and ask them to prepare everything.

It'll cost a little more but the preparation time is practically eliminated, giving you more family time, more time to watch football while consuming your favorite beverage, and you can always blame the chef if everything isn't perfect.

Anyway...it works for me.