Hot Smoking of uncured meat flavors the meat with smoke and cooks it, all the while maintaining a safe bacteria killing temp.
Cold Smoking, actually Cool smoking, takes place between 100 and 170°F. Animal fat melts between 130 and 140°F. At these temps fat melts slowly. At 180+ fat renders quickly and with sausage we experience Fat Out. This is the reason for not going over 170°F. Smoking at these low temps, in a reduced oxygen environment like a smoker, can lead to bacterial growth. Although once the surface temp exceeds 130°F the bacteria begin to die, deadly Toxins are produced, at lower temps, by some types of food borne bacteria that are not affected by heating. It is these Toxins that are of the biggest concern.
True Cold Smoking, like for Belly Bacon and Country Ham, takes place at an ambient temp, no heat generated, of 40° to 100°F for 12 hours to several days or weeks. These temps are the dead center of the bacterial growth Danger Zone and these meats Must be Cured with Nitrite or an internal salt content approaching 10%.
Don't confuse Hot Smoked meats like ribs, pulled pork, beef brisket and smoked Fresh (Uncured) Sausage like, Brats, Italian, Breakfast, etc, that are smoked AND cooked at the same time, with Cold (cool) Smoked CURED meats like Canadian Bacon, City Ham, Smoked Picnic Sholder, Disney Turkey Thighs and Cured Sausage, like Kielbasa, Smoked Country Sausage, Summer Sausage, Andouille and Portuguese Chourice. The latter group is smoked at 100 to 170°F to an Internal Temp of 145-155° and require no further cooking, unless you wish to heat them.
With Hot Smoking Sausage, some fat is rendered but with the short cooking time, 2 to 3 hours, it is limited as long as you start with 20 to 40% fat in the sausage to begin with. Other Hot Smoked meat, Pulled Pork, Ribs, etc, you WANT a good portion of fat to render so you don't end up with greasy meat. I hope this clears up the process for you...JJ
