Homemade Sausage Making

Had time to kill in a supermarket and looked at the label of a mass produced sausage.

Meat 88% (Beef, Pork), Water, Salt, Dextrose, Spices, Mineral Salts (450, 451), Preservative (223), Spice Flavouring, Edible Casing.
Dairy Free

Energy (kJ) 1187
Protein (g) 14.9
Fat - Total (g) 24.6
- Saturated (g) 11.0
Carbohydrate (g) 1.4
- Sugars (g) 1.1
Sodium (mg) 800
per 100g*

I am not great at maths, but this is suggesting 8 grams per kg. However What are mineral salts, and how much do they constitute per kg?

Salt has 394 milligrams of sodium per gram. Work with that tidbit and see if it helps. Also check if the nutrient values were based on a serving and what the serving size was specified.

The mineral salts are phosphates, 450 is diphosphate and 451 is triphosphate.
It's impossible to determine how much was used by the information given.
Check phosphate legal limits in your country, that will give you an idea.

Mark I see now that the number are per 100 grams. So 800 mg sodium per 100 grams would indicate about 2 grams of salt per 100 grams so about 20 grams of salt per kilo. about 2%