*DISCLAIMER* I have tested this recipe and found that it falls well within safe pH levels. However, since pH levels vary, the USDA recommends using 2 tablespoons of vinegar per quart of tomatoes. I recommend testing the PH of your sauce to make sure it is at 4.5 or below. Use other precautions, such as washing your tomatoes in a vinegar-water solution, using only blemish-free tomatoes and processing for the recommended amount of time.
Water Bath Canning Instructions