If you cook for vegetarians, you will need vegetable stock on hand: so many dishes are improved by substituting stock for water. It’s hard to find the good stuff at the grocery store, so make your own at home. Let’s talk about pressure canning vegetable stock.
Late summer or early autumn are the best times to put up vegetable stock, as the main ingredients are abundant and cheap. Here’s a great version that’s full of flavor, easy to make, and straightforward to preserve.
Pressure Canning Vegetable Stock
- 2 Tbsp oil
- 2 large carrots
- 2 large stalks celery, with leaves
- 4 medium onions
- ½ lb fresh mushrooms
- 2 large cloves garlic
- 6 large leaves romaine or Swiss chard
- 1 large tomato, fresh and ripe (or use 2 plum tomatoes from a can, crushed)
- 3 sprigs fresh parsley
- 4-5 quarts water
- Crush the garlic cloves and chop all the other vegetables coarsely, including the greens. Don’t bother to skin or seed the tomatoes. Add other vegetables if you wish, but not any from the cabbage family, as those will make a smelly end product.
- Heat oil in an 8 quart stockpot over medium-high heat. Add the carrots, celery, onions, and mushrooms. Cook, stirring often, 10 minutes or so, until the onions are golden brown. Stir in the crushed garlic, and cook a bit more, until the garlic releases its fragrance.
- Add the greens, tomatoes, and parsley. Add enough water to cover the vegetables by at least 4 inches. Bring to a boil, then partially cover, reduce the heat, and simmer slowly for about 2 hours.
- Strain into a large bowl or pot, pressing down on the solids to extract as much liquid as possible. Cool and chill at least overnight.
- After the stock is well chilled, you can skim off the solidified oil, then freeze or can. To freeze the stock, ladle it into proper containers or zip bags, seal, label, and freeze. To can the stock, you will need to bring it to a boil one more time.
TO PRESSURE CAN THE STOCK
- Preparation: start with clean, hot jars. Check your jars carefully for any nicks – don’t use any flawed jars for canning. They must be clean but need not be sterile. If you’ll be starting with hot broth, use hot jars and hot water in the canner to begin: remember to match the temperatures and you won’t lose jars to thermal shock.Have clean jar bands handy. Put clean lids in a bowl, and pour very hot water over them; hold until you're ready to use them.
- Fill the pressure canner to the proper level (usually marked on the inside.) I like to add about a tablespoon of white vinegar to this water, which keeps film from my jars once they’re canned. Heat the water, so that when the hot jars go in, the water is also hot.
- Heat vegetable stock to a boil. Ladle hot stock into hot jars, leaving one inch headspace. Wipe rims, center hot lids on jars, and apply the bands. Tighten the bands only fingertip-tight: they shouldn’t be cranked on too hard.
- Close the pressure canner, and follow instructions to process filled jars at 10 pounds pressure for 30 minutes (pints) or 35 minutes (quarts) – you may need to make adjustments for altitude. Once the time has ended, let the canner stand to cool and return to zero pounds pressure on its own. When it may be opened, remove jars to a towel-lined counter, and let them stand for 24 hours, then check the lids for proper seal. The lids should not flex up and down when the center is pressed.
- Label the jars carefully: vegetable stock looks just like chicken stock, and you don’t want to mix them up!