From their website:

The manufacture of real, old fashion pepperoni is a tricky, time-consuming process. Drying is the most difficult part because a humidity-controlled room is required. The fermentation process, which uses a starter culture, is expensive and time consuming. Many medium sized meat processors refuse to make pepperoni because of these reasons.

By adjusting two steps of the formula and procedure, however, one can make a pepperoni stick at home. Reduce the diameter of the pepperoni from a typical 1.5 inches to that of a hot stick (0.75 inches, or 23 mm) so that it can dry properly, and switch from starter culture to encapsulated citric acid, as described below.

To make 25 lb of Pepperoni Stick

Meats:
 25 lb of ground meats

Suggested meat blocks:
  Block 1: 12 lb deer, 7 lb beef, 6 lb pork
  Block 2: 12 lb beef, 13 lb pork

Seasoning and Other Ingredients:
 Package of Italian Hot Sausage Seasoning #867 17.2 ounces (approx cost $4.00)
 Package of Tinted Curing Salt #906 1.0 oz (approx cost $0.35)
 Two packages of Encapsulated Citric Acid #261 2.0 oz (approx cost $1.80 each)
 Package of 23mm Edible Collagen casings #2876, two 66-foot strands (approx cost $10.85)

Procedure:
Cleanliness is very important. Clean meat lugs and utensils thoroughly, sterilize with dilute bleach water, scrub and rinse thoroughly. Wash hands thoroughly with anti-bacterial soap, and be careful about cross contamination. Have ingredients laid out and ready to go. If mixing by hand, wear clean rubber gloves if possible. This should be standard operating procedure with any sausage making. Nothing reduces sausage shelf life more than bacteria and thermal abuse.

Place meat in mixing lug, add curing salt and mix briefly. Add hot sausage seasoning and mix thoroughly. Mixture will become very stiff as the protein is extracted from the muscle cells.

Sprinkle the encapsulated citric acid over the meat mixture and fold into the meat with a minimum of mixing. Reason: Premature acidification interferes with the binding characteristics of the protein, so the citric acid crystals are coated with a palm and coconut oil blend to prevent contact with the meat. During cooking, the binding properties are set up at about 125 degrees F. At about 135 degrees F. the palm oil coating melts, releasing the citric acid, which gives the pepperoni it's characteristic tart flavor. Over-mixing will break off the palm oil coating, exposing the meat to acidification too soon. With premature acidification, the final product would be too soft, and wouldn't have that typical firmness.

Stuff the pepperoni into the 23mm collagen casings not with a grinder, but with a stuffer. The reason is the same as above. The twisting action of the grinder worm breaks off the palm oil coating from the citric acid, causing premature acidification. Con Yeager Spice can rent you a 5 lb stuffer for $10 per day, $15.00 per weekend, if you are handy to Zelienople and no other stuffer is available.

After stuffing, cook the pepperoni either in your oven at the low temperature setting, or in your smoke house. If using a smoke house, you can give it a light smoke. The amount of time this takes is dependent upon many factors, including the temperature and quantity of the meat, ambient room or outdoor temperatures, and the insulating characteristics of your smoke house or oven. Check the internal temperature of the meat. When it reaches 155 degrees, it's finished. Immerse the pepperoni in ice water immediately, so it stays plump. Once at room temperature, hang to surface dry for a few hours in the cooler or refrigerator.

At this point, the pepperoni can be packaged, or be left in your refrigerator or cooler for further drying. (Remember to NEVER package warm meat.) Dry to desired hardness. Since this product would be more likely eaten directly than sliced, do not dry it too much. Drying the pepperoni in a paper bag in your refrigerator helps to control the drying process, making the finished product uniformly dry, and avoids the "hard shell" appearance of product dried too quickly.

One final note:
Semi-dried sausages commonly develop a whitish material on the surface. This is not normally mold, but salt deposited by water migrating to the meat surface and then evaporating, leaving the salt behind. Just rinse and scrub it off. Properly handled semi-dried sausages do not usually develop mold because of low water content.

Disclaimer:While the formulas and instructions are accurate to the best of our knowledge, the Con Yeager Spice Company cannot accept responsibility for product failure or lack of acceptance.