Smoke is a necessity of barbecue in order to give the meat that signature flavor that cannot be created any other way. By placing the meat in a smoker, surrounding it with flavorful smoke, and letting it cook at a low temperature for a long time, you make a tender and tasty meat, a method that is ideal for pulled pork.
In addition to a smoker, you need a type of fuel to maintain a low level of heat for an extended period of time; this can be charcoal or wood. Depending on what type of wood or charcoal you use will affect the flavor of the smoked meat.
Choosing a Fuel
Purists will say that your fire should be made entirely from hardwood logs that have been burned down to coals and then added to the smoker. Of course, this isn't practical for everyone. Whether limited by equipment or temperament, many people find it difficult to burn hardwood logs to create the kinds of coals used by diehard traditionalists.
If you do go with charcoal, you will benefit most from hardwood charcoal, but you can, if need be, use regular charcoal. It's ideal to stay away from charcoal with additives like lighter fluids. If you are using charcoal, add presoaked hardwood chunks (not chips) to the coals once the fire is good and hot. Make sure to drain off as much water as possible; the wood should be moist, not wet. During a long smoking period, you will probably have to add burning coals to the fire to maintain the temperature and additional wood chunks to maintain smoke.
Choosing a Type of Wood
What type of wood you use for smoke is up to you. What works best, however, are the Southern traditional woods: hickory and oak, particularly white oak. Also, pecan, walnut, cherry, apple, and peach are good choices. You should stay away from alder and mesquite because they tend to add a strong flavor to meats. Despite how long the meat is cooked, it should be exposed to smoke for at least the first 6 hours.
Setting the Temperature
The ideal smoking temperature is around 215 F with the acceptable ranges being between 215 F and 235 F. Under normal conditions, you should plan on smoking for about 1 to 1 1/2 hours per pound, but keep in mind that the temperature modifies the cooking time. If you smoke on the higher end of the temperature range, subtract about 10 minutes per pound. This means a 10-pound pork shoulder can take 15 hours to finish.
Although there is still debate on the subject, conventional wisdom suggests that the amount of smoke flavor absorbed by meat declines as it cooks. Therefore, the amount of smoke flavor added in the last 2 hours is relatively insignificant. If you find it difficult to maintain a good temperature for this long (as many people do), you can wrap the pork in foil and place it in the oven.
That being said, it is best to keep meat in the smoker for as long as possible. If it becomes difficult to maintain the temperature, or other circumstances get in the way, move the pork to the oven that has been set to the ideal temperature range. Make sure you wrap the pork tightly in foil to hold in the moisture. Many people, even competition cooks, will smoke their pork roasts unwrapped for half the overall cooking time and then wrap.
Pulling the Pork
Once the meat reaches an internal temperature of 180 F to 190 F, it is ready to be pulled. You can serve the meat once it reaches 165 F, but it won't be tender enough to pull apart properly. Make sure to keep an eye on the internal temperature and not to cook the pork above 190 F as the chance of the meat drying out increases.
Remove the pork from the smoker (or oven as the case may be) and let it sit for about an hour. This will cool it down enough for pulling. As you pull the meat apart, place it in a pot on a low temperature to keep it warm. You will need to separate the meat from remaining fat, bone, or other unpalatable parts. From here you can serve as is; however, many people prefer a finishing sauce, so it's best to have one ready.