Smoking a pig at 225 F vs barbecuing one at 250F?

You may want to check out the following pages:

What Influences Cooking Time

Thermodynamics of Cooking

Using their methods, I have not had a shoulder take 15 hours to come to temperature at a smoker temperature of 225 (computer-controlled). I have never done whole hog, but as Jefromi stated the actual method of cooking makes a significant difference. The Hawaiian imu (the bury-it-in-the-ground style of cooking using the retained heat from sand and rocks that were under the coals) is a much more efficient way to rapidly transfer the heat to the meat than using air to conduct the heat, and forced convection from the blower in my smoker is more efficient than natural convective currents. If my smoker did not have the blower it would take longer to get the meat to temperature, but I still don't think it would take 15 hours for a shoulder.

Whole hog weight versus time at 250 degrees:

• 40 pounds: 3.5 hours
• 75 pounds: 9 hours
• 100 pounds: 12 hours
• 125 pounds: 15 hours
• 150 pounds: 18 hours
• 175 pounds: 21 hours
• 200 pounds: 24 hours

From Goin' Whole Hog

AmazingRibs.com is essentially a peer-reviewed barbecue site. They don't publish a recipe until it has been tested multiple times and is nearly foolproof. They also bust some of the barbecue myths that have been spread for generations. I am not affiliated with it other than donating some money to them due to their high-quality articles.

It is not viable to compare cooking times for a single shoulder with that for a whole hog. There are some reasons for this:

1. Surface area is the biggest factor in determining cooking time per mass. A 9-pound pork shoulder may take 12-16 hours to cook whole, but if you were to butterfly it, the cooking time would be drastically reduced. You may have a 90-pound hog, but you are exposing a much greater amount of surface area to cooking at one time.
2. You are not going to cook a whole hog to nearly as high a temperature as you would a pork shoulder. If you are only making pork shoulder or pork butt, you can cook it to 195f+ with no problem. It will be moist, tender, and pull apart easily. When you're doing whole hog, you're also including a lot of pig (loin, back, etc) that is not so amenable to cooking to that temperature. The latter is cooked to a lower temperature, and is chopped to help tenderize it.

1) A "market" size pig, i.e. one they cut up and sell in pieces at the grocery store is much bigger---(250 lbs or so) than a 90 lb. "roaster." Cooking time depends on the largest cut, so a shoulder from a market pig will be larger than the shoulder from a roaster, thus taking longer to cook;

2) 25 degrees does make a very big difference in cooking--yes, hours;

3) 6-7 hours for a 90 lb pig at 250 is not enough time in my experience. I cook ribs for 5 hours at that temp--no way the shoulder or ham is getting done to an internal temp of 195-200 in that time. I have not cooked a 90lb pig, but the 65 lb ones I have cooked took over 7 hours cooking at temps higher than 250. A lot of the recipes for cooking whole hog use homemade cement block pits--not exactly precision cooking instruments. There may be a thermometer somewhere in the pit that reads 250, but that may not be the temp at the meat which is exposed to the coals.

So, yes it could take 15 hours to cook a big shoulder at 225. It will take much less time to cook a 90 lb roaster at 250, but more like 10 hours.

If you're aiming for an internal temperature of 195F, the difference between 225F and 250F is huge. Heat transfer rates are proportional to the temperature gradient, or roughly, the difference in temperature between the hot part and the cold part. Say you're trying to get those last 5 degrees, from 190F to 195F in the middle. If the hot part is 225F, you've got a difference of 35F; if it's 250F you have a difference of 60F, 1.7 times as much. So you'd expect it to take (very roughly) 70% longer at 225F.

And yes, the depth the heat has to penetrate (the distance from the surface to the center of the meat) has a similar effect, but from what I understand, when you're roasting a whole hog you flatten it out somewhat so that the thickness isn't actually that much larger than a pork shoulder.

(Still, as RudyB said, 15 hours is a pretty long time; it might be overkill.)