The Panofsky turkey constant
November 26, 2008 | 12:06 pm
Just in time for the Thanksgiving holiday, Nicholas Panofsky shares a flavorful tidbit of Panofsky family lore.
“There was a point in time when my grandfather [SLAC Director Emeritus] WKH ‘Pief’ Panofsky was not satisfied with the cooking times for turkeys of ’30 minutes per pound’,” Panofsky wrote. “This is of course reasonable, because the time a turkey should be cooked is not a linear equation.”
So Pief Panofsky derived an equation based on the ratio between the surface area and mass of a turkey. Cooking time for a stuffed turkey in a 325 °F oven is given by
t = W(2/3)/1.5
where t is the cooking time in hours and W is the weight of the stuffed turkey, in pounds. The constant 1.5 was determined empirically.
This story first appeared in SLAC Today.
Shawne Workman
Posted in Uncategorized |
9 Comments »
November 27th, 2008 at 3:33 am
I guess t should be in hours, not minutes…
November 28th, 2008 at 3:10 pm
This seems wrong. It surely takes more than 4.912 minutes to cook a 20 lbs turkey…
November 28th, 2008 at 7:23 pm
I think it should read “t is the cooking time in hours” instead…. Cooking a 20lb Turkey, say, ought to take longer than 5 minutes, shouldn’t it? Perhaps I’m dealing with inferior ovens.
November 29th, 2008 at 4:27 am
It shows that Pief was a curious man and could observe his environment.
November 30th, 2008 at 1:16 pm
Theory is fine but, experimentally, we have found that:
” All turkeys cook in 4 hours!” (nearly). This seems to be relatively independent of whether it is filled with lemons, onions etc, or with “stuffing”, a rather poor conductor of heat. Even assuming a spherical turkey I’m sure the theorists would have fun calculating the affect of the varying contents.
December 1st, 2008 at 11:34 am
Indeed the time should be in hours, not minutes. Thanks for the catch, all.
December 3rd, 2008 at 9:28 am
And technically speaking it was first published in Physics Today magazine. There’s a particularly good summary in an article called “The Science of Cooking” that will be available on the web site in the New Year.
December 3rd, 2008 at 10:35 am
@Paul: Hi Paul, do you have a reference from PT for the original? (Then I can add it to the story.) This info was sent direct to us by Nicholas, without a mention of any previous existence in PT. Thanks!
February 27th, 2009 at 7:41 pm
MKS
t should be in seconds..
W should be in Kg, and the temperature would be in Kelvins.