PULLED / SHREDDED MEAT COOKING GUIDE
There are a lot of variables to test and play with to arrive at the perfect pulled or shredded product. The most important factor is to hold the meat internal temperature at 90C+ for a period of time to ensure that the collagen connective tissue between muscle fibers dissolves into gelatin. Depending if you want 'completely' shredded, or 'partially' shredded chunky, you can play with time and temperature. For shredded chicken breast, as an example, we would recommend a steam cook for 1:15 to 1:45, depending on how finely shredded you want it. It really takes some time initially to work out the best cooking time to get the desired results.
For USA style BBQ pulled pork, most manufacturers in the states use Pork Shoulder, Pork Butt, or what they call Pork Cushions, and lastly, Pork 'Picnics'. The shoulder is very large and has large 'fatty' areas, so it is only recommended for smaller scale producers or home users, as you must remove the large fat pockets prior to shredding. The best product (highest quality) is the pork picnics shredded, followed by the pork butt. Picnic shoulder are from the thinner, triangle-shaped end of the shoulder, whereas the 'butt' is from the thicker, more intensely marbled end of the shoulder.
Many processors add the ingredients and cook the products in a bag by steam cooking for extended periods of time. The main factor is the thickness of the product, due to needing to hold the internal temperature up for extended period. For example: if you have two 4 kg pieces of pork that I want to cook properly to shred and one is shaped like a basketball and the other is long and flat, then the long and flat one will be ready to shred in about half the cooking time.
For pulled pork - manufacturers add ingredients (seasoning, etc), sometimes pre-tumbled with the added ingredients, into a bag that is sealed for steam cooking. Try and lay out the bag so that it is as flat as possible on the cooking rack. Step cook (70C 1 hr, 80C 1 hr, 90C 1hr, then hold at 95C for long time.) The most important factor is that the internal temperature is held at 90C+ for over an hour (at least.)
HOW TO SHRED THE MEAT
The shredding of the meat must be done whilst it is still hot/warm and the temperature that the meat is shredded at plays a large part in determining the coarseness of the final shred. By letting the meat cool from its final cooking temperature of at least 95 degrees Celsius, a thicker more course shred is possible, for a very fine shred, transfer straight to the shredding machine from the smoker or oven.
Remove the meat from cooker and when you open the bag, capture the juices from the bag to add back into the shredded product. Remove the product and put into your shredder and slowly add whatever fat/moisture was left in the bag. In the USA, the product is usually packaged in a gas flush tray sealer or tray former, where they add a cold BBQ sauce to product, then it is chilled as fast as possible.