Ken Albala is the author of The Lost Art of Real Cooking with Rosanna Nafziger. He recommends using shoulder meat, chop it finely and then add salt, nitrates and seasoning. Use a funnel to get it into the casing. Ken also used beef bungs to make dried Italian sausage. He uses nitrates when making salumi, and he argues that it's impossible not to.
Sweet Italian Sausage
from Sausage by Victoria Wise
1 3/4 lbs ground pork
1/4 lb salt pork, fat part only, minced
2 cloves garlic, minced or pressed
1 tsp chopped fresh oregano or scant 1/2 tsp dried oregano
1 tsp dried thyme
2 tsp fennel seeds
1/2 tsp freshly ground black pepper
1/8 tsp cayenne pepper
1/2 cup white wine
1 tsp kosher salt
Place all the ingredients except the salt in a large bowl, and knead with your hands until thoroughly blended. Cook and taste a small sample, then add the salt if needed. Leave in bulk and shape or stuff into hog casing. Cover and refrigerate for several hours, or preferably overnight to allow flavors to blend.
Saute or grill. The uncooked sausage will keep in the refrigerator for up to 3 days, or in the freezer for up to 1 week.