Have been looking at Marinara canning recipes non I have found call for lemon juice at the end.

Question

Most tomato recipes for canning do. Does anyone know why the difference?

Answer 1

I'm sorry, I can't understand your question at all.

Answer 2

Tomatoes are very acidic which makes them able to be canned in a water bath safely.  However, when you add other ingredients for sauces or salsa the mixture may not be acidic enough .. so, adding lemon or lime juice to each jar brings the acid level back up to safe standards.