Pressure canning can be a bit intimidating. I know it was for me when I first started, but sooner or later you just have to do it: face that fear of the shigity-shhi-sh-shaker weight and learn to love the steam bomb (I’m aware I just said “bomb” in a post about pressure canners. “Honey, someone’s at the door…“) This post is not in any way meant to be comprehensive guidance to pressure-canning, but rather a demonstration of the tried-and-true recipe that I used to get my feet wet with the process. It’s an easy recipe and the risk of failure is pretty low. And this salsa is a lot like wine: every batch is unique depending on the ingredients you use, the ripeness of the tomatoes, the mix of red and green peppers, different types of onions. You’ll never eat stale, lifeless franken-salsa from the grocery store again.
First off, I can’t recommend highly enough “Putting Food By”. The go-to guide for food preservation. Also, the USDA is doing something positive with your tax dollars over at the National Center for Home Food Preservation. They have a free canning guide that is also an invaluable resource. Download it and kill a tree to print it out – it’s worth it.
Caveat-emptor: Lots of internet recipes and even the USDA’s own canning guide recommend boiling-water bath canning for salsa. I personally don’t risk this. Salsa is a mix of high- and low-acid foods and low-acid foods require pressure-canning. With salsa, you are relying on the acidity of the tomatoes to protect your food when using a boiling-water bath. It is difficult to ensure the exact ratio of tomatoes to the other low-acid ingredients in salsa, and the acidity in tomatoes can vary wildly. I just pressure-can it to be safe, as directed in “Putting Food By”. In fact, the original recipe is in the book.
What you’ll need
- 5 Pounds of vine-ripened, firm paste tomatoes
- 2 pounds of peppers, mix sweet and hot to your own taste
- 1 pound of onions
- 1 cup of vinegar
- 1 Tbsp of kosher or canning salt
- ½ tsp of black pepper
- A pressure canner
- (Optional) A Roma or similar food mill
Yields exactly 6 pints. Rarely any leftover for a snack.
Mise En Place
As they say in professional kitchens, mise en place, which is French for “everything in its place”. As you can see in the photo, my ingredients have been chosen and cleaned. They are all fresh out of the garden. The tomatoes are a mix of Gilbertie and Roma paste tomatoes. Firm, just-ripe paste tomatoes give the best salsa, as slicing varieties or tomatoes that are too ripe produce watery salsa. I also try to pick smallish, misshapen onions for salsa and save the good looking ones for storage. I used a mix of red and green peppers for color and to add complexity to the flavor. For the record, those jalapenos turned out to be so hot, I only used *2* of them in this batch, and that might have been too much. The Roma food mill is set up and all the processed ingredients will go into the non-reactive pot to be simmered down. And as always, I have my recipe and the manual to my pressure-canner handy. Not pictured are the half-dozen pint-sized canning jars that have been washed and are sitting in a 170-degree oven to keep them hot. I don’t believe in sterilizing my canning jars unless the processing time is less than 10 minutes. I simply make sure they are washed well before canning. Really, they’re going into a 240-degree pressure-canner – sterilizing them beforehand is just a wasted step, in my uneducated opinion.
Processing the Ingredients
With the tomatoes, I chop off the shoulders and any blemishes, quarter them, and toss them into the Roma food mill. The Roma is set up with the accessory Salsa screen, which has large holes allowing for most of the seeds and chunky meat to pass through, while precluding most of the skin and core. The processed tomatoes are added to the pot. If you don’t have a Roma, you could par boil the tomatoes to slip the skins off, core and chop by hand. The Roma food mill saves time in this respect (which, granted, is later lost having to clean the food mill).
Next I chop up the peppers and onions. I prefer a chunky salsa, so these are roughly chopped and tossed into the pot. I make sure I get as many pepper seeds into the pot as possible, as these are a very important source of flavor (and heat, if you’re using hot peppers).
Finally I stir in the kosher salt, pepper and vinegar. I put the pot over medium heat, cover, and bring it to a simmer. I hold it there simmering 10-15 minutes.
Prepping the Pressure Canner
While the salsa is simmering, I prepare my pressure canner and start heating it up. First, and most important, is to always follow the manufacturer’s directions when using a pressure canner. They are all slightly different and require different set up. Check your Instruction Manual. But here are some general checkpoints I follow:
- I check the structural integrity of the canner. I look for any visible cracks. I check the rim for chips that would prevent a good seal.
- I check the rubber relief valve to make sure it’s still supple. I also check the vent hole and the pressure gauge holes to make sure they aren’t clogged.
- I check to make sure all the locking handles are operational.
- I make sure I have a metal rack in the bottom.
- I make sure I put the recommended amount of water in the bottom before I put jars in.
Jarring it Up
When it’s done simmering, I ladle the hot salsa into my hot jars leaving 1” of headspace. I go back and scrupulously clean the rims with a clean, damp paper towel. I find I have sealing problems with Tatler reusable canning lids if the rims are not squeaky clean. I center my Tatler rubber ring and lid on the jar, screw on a metal band until snug, then back it off 1/4″ so the Tatler lids can vent during processing.
The jars go into the canner and I make sure they aren’t touching each other. The canner lid goes on and is secured. At this point, the regulator weight is OFF. This is often a missed step by those new to pressure canning: you must vent the canner properly to exhaust all the internal air and have it replaced with steam. This requires that you heat the canner until a steady jet of steam is exiting the vent hole for a solid 7-10 minutes. Again, follow the manufacturer’s directions for exhausting your canner – each one is different depending on the size, etc.
After the the canner has been exhausted, using an oven mitt, or similar, I place the regulator weight over the vent hole. Its important to be careful here – the jet of steam coming out of the vent hole is in excess of 220-degrees and will seriously burn me right quick.
Now, the Zen of pressure canning and heat management must be learned. Every stove is different and you have to experiment to find that heat setting sweet spot where the regulator is jiggling about every 10 seconds. A constant jiggle is unnecessary and potentially dangerous: too much steam and it’s possible to boil the canner dry. Boiling the canner dry is bad juju – you will likely warp and ruin the canner.
It’s important to note that the regulator weight, and not the pressure gauge (if you even have one), is the authority on pressure in the canner. The pressure gauge is a guide only. They can and do fail and their accuracy can be questionable. Only the jiggle of the regulator weight every 10 seconds or so is the correct indicator that proper internal pressure has been reached.
Once and only once the regulator weight starts to jiggle every 10 seconds, do you starting counting processing time according to the recipe. Sometimes after exhausting, the pressure will still be low and the regulator weight won’t jiggle for quite a few minutes after being placed over the vent hole. You don’t start counting processing time until you’re sure you’ve got a good jiggle every 10 seconds.
And now another critical point: after the recipe’s stated processing time, I simply shut the heat off and leave the canner alone. Obviously do not attempt to open the canner right away, but also, don’t attempt to vent it early. Leave the regulator weight on the canner and let the pressure come down slowly to zero on its own. Venting it early is like giving your canning jars “The Bends”. When a scuba diver comes up too quickly, the pressure inside their body is not equalized to the pressure outside and bad things happen. If you exhaust your canner too quickly by pulling the regulator weight off, the pressure inside the canner will drop rapidly, but the pressure inside your jars will remain high. This could lead to a loss of liquid inside the jars as it’s literally blown out from rapid decompression. It could also lead to a failed seal on your jar altogether where the vacuum is lost. Worst case, a jar could explode if you were doing something that requires high pressure. I can’t stress this enough – leave the canner alone until the pressure comes to zero on its own, naturally and slowly. If you don’t have a pressure gauge to monitor the internal pressure, check it by jiggling the regulator weight with a gloved hand. If any steam whatsoever comes out the vent, leave the weight alone, wait 5 minutes more and then check again.
After some time, the magic moment arrives: the internal pressure is zero and it’s time to open the canner. While the pressure is zero, there is still hot steam inside. When I open the canner I make sure to lift the lid away from me so my arm doesn’t get a steam burn. I remove the jars and tighten the lids per Tatler’s instructions.
After the jars have completely cooled, I remove the bands and check the seals. I tug on and slightly twist the Tatler lids to make sure they are completely sealed. I lift up the jar off the counter by the lid and make sure it stays on. Any failed seals get capped and put in the fridge to be consumed soon. I then wash the jars in hot soap and water. There’s usually a funk on the outside of jars from when I filled them and some of the liquid venting into the canner. This funk could lead to a failed seal eventually, so I clean the lid and the exposed ring, as well as the jar. Also, this funk makes your food storage area smell, well, funky. Once clean and dry, they are labeled and put in a cool, dry, dark space in the root cellar to be enjoyed in the coming years. And I mean years: It usually doesn’t last long, but I’ve cracked a forgotten jar of salsa that was 3 years old and it was still delicious.
Pressure canning is a fear we all have to conquer sometime. With modern equipment, tested recipes, and attention to detail, it really is foolproof. It also opens a whole new home-canning world beyond high-acid tomato products and high-sugar fruits and jams. Hear that shicka-shaka-shaker weight a jigglin’? That’s the sound of Freedom!