The Basics of Slaughtering Hogs

The following post will describe how to humanely and cleanly slaughter and prepare hogs for refrigeration. After initial processing, hogs must remain refrigerated at 33–38 °F for a minimum of 24 hours.

Stunning

The ideal way to enhance control and maneuverability of a hog is to utilize stunning. Varying methods of stunning include the use of electric shock, bolt guns, and firearms. When stunning the animal, it easiest to picture an “X” with lines drawn from the animal’s eyes to their opposite ears. Placing the electric probe, bolt, or barrel of the utensil used for stunning in the center of the “X” will ensure a good, clean stun that will render the animal brain-dead.

In order to evaluate the stun, one can either poke the animal’s eyes to check if their blinking reflexes are still intact, or one can listen for any squealing coming from the stunned pig. Both blinking and vocalization after stunning indicate a bad stun. If either of these indicators are present, it is important to move to the next step as soon as possible. Otherwise, the stress induced by a misplaced stun will initiate the animal’s fight or flight instinct and, in turn, may ruin portions of the animal’s meat.

Bleeding

The next step is to drain the blood from the hog. This is best done by hoisting the hog up by their hind legs allowing its head to hang several inches above the ground. The reason this is done after the stun is due to the fact that the heart will continue to beat several minutes after the brain dies. Most likely, the animal will begin to twitch violently after the stun. These convulsions are simply the effects of a dying brain and need not cause any alarm. However, these twitching actions make hoisting the animal rather difficult and processors should be mindful of the kicking legs.

Once the animal is hoisted, a processor should utilize a sharpened knife to puncture the hog’s hide and hopefully “stick” its heart. One should puncture just above the crest of the hog’s chest cavity. When “sticking”, one should aim his or her knife blade-up and at a 45° angle up. Before the puncture, one should be able to draw an imaginary line from the tip of the knife to the center of the upside-down hog’s spine. Once the knife has entered the chest cavity, an upward slice will aid in the bleeding process and should provide a larger whole for the blood to drain through.

Scalding or Skinning

Oftentimes, butcheries utilize a scalder to remove all of the hair on the hog. Hogs are placed in a large tub-like machine filled with rubber cogs and scalding chemical. Once inside, the processor will shut the lid to the scalder and turn it on. The rubber cogs will continuously rotate the hog inside the warm scalding chemical which effectively removes the majority of the hog’s hair. After about 120 seconds, the processor will halt the machine, open the lid, and hoist the animal out of the scalder to be shaved.

Shaving the hog ensures that the remaining hair is removed. After the hog is hoisted, processors can begin shaving the hog from the tail to the neck (or top to bottom). Once the hog is free of hair, it should be thoroughly rinsed.

Head Removal

Decapitating the hog is the next step. Utilizing the same knife used for the “stick”, the processor should place the blade just above the ears on the top of the hog’s neck. In a sawing motion, bring the knife down one side of the hog’s head. Most likely, the knife will hit the base of the hog’s jaw line. Turning the knife sharply upwards and following the edge of the jaw should ensure a nice, smooth cut all the way through the bottom of the neck. Do the same for the other side. Next, focus on severing the throat and joints from the head. The processor should feel a slight release in pressure. If the head does not naturally fall at this point, a sharp twist should cause it to fall.

Intestine Removal

After Head removal, the body should be laid on its back with the feet pointing upwards. One should then slice open the chest cavity by cutting a straight line from the base of the sternum to the neck. A hack saw must then be used to saw open the sternum. Once this is complete, grab the bulge at the top of the esophagus and begin cutting around it. Processors should then cut the pericardium and peritoneum (the membranes separating the heart from the organs) at the point where they attach to the rib cage. Once these are severed, firmly grasp the esophagus and pull upwards and back towards the tail. The entire gastro-intestinal tract should then loosely peel off the hog’s spine.

Lastly, spread the hog’s hind legs in preparation for the removal of the large intestine and anus. Similar to the esophagus, grasp the anus and begin cutting around the large intestine to the point where one can grasp it with one hand. Tie off the anus to prevent leaking of any excrement. Once the tract is sufficiently severed from the surrounding muscles, pull upwards and back to wards the head. The tract should then be easily severed from the body with a few more slices and easily displaced with one hand.

Halving

Once finished with intestine removal, hoist the animal up one final time. This time, slits can be cut along the tendons just above the hind hooves. Subsequently, hooks can be inserted through the slits, and the hog’s body can be hoist up with its hind legs being spread apart. Once the legs are properly spread, the processor can cut downwards along the hog’s spine. This will “half” the hog.

Preparation for Refrigeration

The final steps before refrigeration include removal of the membranous spinal cord, trimming of the teets, and stripping of the inner fat. One can accomplish spinal cord removal by simply running his or her thumb along the “halved” spinal cord, removing the membranous material within. Next, the teets must be cut off. Grasping a firm hold of the top-most teet, cut downwards until the last teet is severed from the hog’s belly. Lastly, grip the inner fat along the inside of the ribcage with two hands and pull upwards. This allows for easier fat removal after adequate refrigeration takes place.

Refrigeration

Now the hog is properly prepared for refrigeration. Hogs should remain hanging in the refrigerator for a minimum of 24 hours. Once complete, processing of the hog’s meat can begin.