When cooking for mixed crowds, I calculate 1/3 of a pound of cooked meat per person. The females will eat less, the males most times will eat more, the elderly will eat less, and the young will also eat more. This calculation has always left me with just a little left over, but I feel it is better to have a little extra than not enough.
Calculating for teens can be tricky, as sometimes they eat much much more than an adult can eat. Also couple the fact that some are picky eaters and some may not eat salads.
Smoke on Badger Mountain is right on the money.....
If you are doing a whole pork shoulder, after cooking loss, removing the skin, fat, and bone, your approximate meat yield will be about 40% meat.
To calculate for 200 people at 1/3 pound of meat simply divide the number of people being served by 3, this will give you the amount in pounds of cooked meat you will need. 200/3 = 67 pounds of cooked meat needed, multiply that by 2.5 to get the amount of raw pork shoulder needed to cook.
200/3 = 67 cooked meat 67*2.5=167.5 raw meat
To backwards check your work, take the amount of raw pork and multiply by .4 to find your cooked product weight, them multiply by three to give you your calculated servings at 1/3 pound per person.
167 pounds of raw pork times .4 (40 % yield) = 66.7 pounds cooked pork. Multiply the cooked pork by the number of servings per pound (3 * 66.7) to get the total amount of calculated servings. 167 * .4 = 66.7 cooked meat 66.7 * 3 = 200 servings.
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