I've been curing and smoking sausage and other cured meats like corned beef, pastromi, hams, and Canadian bacon as a hobby for many years.
I just took out of my smoker a batch of real fermented pepperoni, the 24 hour American style rather than the 6 week Italian style. The procedure for making this stuff amazes me in that it does not spoil.
What I did was mix up the usual seasonings and sodium nitrite cure as I would for a typical smoked Italian sausage. The key spice besides salt and pepper is fennel seed. But what makes this pepperoni a fermented sausage is the lactic acid producing bacteria culture I added, only 1/2 a teaspoon for 5 kg of meat.
The next step is what is amazing to me. I fermented the sausage by holding it at 100F for 24 hours and then raised the temperature to 160F for 6 hours. The salt and sodium nitrite is what keeps it from spoiling along with the culture that makes lactic acid out of the dextrose in the recipe and reduces the pH of the meat to 4.8 or so.
I cheated on the recipe just a little bit. I was supposed to control the humidity to 85-90% but just turned my smoker box on and crossed my fingers. I sampled some last night and it is the real thing. I also haven't developed food poisoning as of this morning! My pepperoni looks and tastes like what is put on pizza, quite salty and tangy.
Next steps are getting an old refrigerator modified with a thermostat to maintain 50-70F and adding a humidistat and a humidifier. With this setup and a different culture, I can make Italian pepperoni which is fermented at 68F and 85-90% humidity for 72 hours and dried for 6-8 weeks at 55F and 80-85%. Also in the card is making real salami by a similar procedure.
