Pressing Canning Ratatouille

With the tomatoes left over from the farmers market this week, I processed and cooked down about three quarts of tomato sauce.  It didn’t seem worth canning that little amount of sauce, so I looked around my kitchen, and realized I needed to deal with the overflowing box of other-than-tomato produce sitting on the kitchen table.

Before the anticipated frost on Wednesday night/Thursday morning, I picked every little eggplant left on my “Lavender Touch” bushes, and I’ve been collecting sweet and hot peppers as they ripen as well.  Add to that a few herbs (rosemary and marjoram), plus salt, pepper, a splash of white balsamic vinegar, three smashed-and-chopped cloves of garlic, and I had a nice pot of ratatouille–about eight and a half pints worth.

Canning a mixed vegetable soup or stew, even with a tomato base, requires pressure processing.  There are some recipes that allow you to boiling water bath can a tomato sauce or soup, true, but with very strict proportions of added ingredients.  With ratatouille, the high percentage of eggplant and peppers means pressure processing is the only safe way to go.

The Putting Food By rule here is to pressure process for the least acid ingredient–that is, process for the ingredient that takes the longest time and the highest pressure.  For this recipe, it’s peppers at 10lbs. for thirty-five minutes.  I also tend to leave a little more headroom in the jars (3/4-1 inch) when pressure-processing, so the high heat doesn’t force the ingredients to boil out of their jars, ruining the seal

A note about jars–I have been collecting and using older canning jars–not the blue ones, or the ones with wire closures, but the Ball Perfect Masons and Atlas Strong Shoulder jars (pints and quarts) I find in the Civic Council.

I have yet to have one of those older jars break in the canner–while the newer jars I buy at the grocery store do tend to lose their bottoms after a couple of seasons of use.  If you buy older jars, do inspect them carefully for hairline cracks or chips in their rims.  They also tend to be cheaper than new jars, unless there’s a market for slightly older canning jars as “antiques” in your area.