Tomatoes are a versatile and nutritious food. They may be eaten raw in salads or as an ingredient in a variety of cuisines, sauces, soups, and juices. They are abundant in vitamin C, carotene, and lycopene and are considered highly healthful.
Tomatoes are canned in a variety of ways, including whole peeled and diced tomatoes, tomatoes with onions and other vegetables or herbs, and various pastes, purées, and sauces.
Canning tomatoes allows you to harvest tomatoes at the peak of their season and preserve them for usage throughout the year. Nothing beats raising your own tomatoes and then preserving them to keep in your cupboard.
Tomatoes, unlike pickles and other fruit preserves, have a low acidity and must be acidified in order to be canned using the traditional water-bath procedure. Foods with a pH higher than 4.6 can harbor botulism bacteria spores; tomatoes have a pH of about 4.5, thus to be on a safer side you need to increase the acid level. Furthermore, adding anything to your tomatoes, such as onions, garlic, or basil, reduces the acidity even more.
- Canning jars
- jar lifter
- spatula, Knife and chopstick
- Pot/kettle for a hot water bath
- If you already have jars, you may use them to make canning lids.
The steps for correctly canning tomatoes are shown here.
- Cut off the rough core of the tomato with a thin paring knife, then score the bottom.
- Set a big kettle of water to boil, and have an ice-filled cooler nearby.
- Boil the tomatoes for 20 to 30 seconds, or until the skins wrinkle and crack.
- Place them in the icy water. Depending on how many tomatoes you’re processing, you may need to change the ice water numerous times because the hot tomatoes will quickly melt the ice.
- Set up a workstation with three positions: a large bowl or pot, another large bowl or pot with a sieve over it, and a pot large enough to hold the tomato pulp while it cooks.
- Now, Take each tomato out of the ice bath.
- Remove the skin and place it in the first dish or saucepan. Tear open the tomatoes and strain the seeds and liquid from the chambers through the sieve in the second dish or pot. Transfer the tomato pulp to the third pot and smash it with your hands. The skins will not want to come off, and the fruit will be too difficult to open and smash if the tomatoes are too under-ripe.
- Massage the seeds in the sieve with a spatula to remove the water. The seeds will keep some of their gelatinous coating. Remove the peels and seeds, but save the tomato liquids. This is incredibly tasty and may be used in the same way as stock, for example, as a basis for soups or braises.
- Heat the crushed tomatoes (or purée) and water in separate pans. Bring to a gentle boil, then turn off the heat. Cook the smashed tomatoes until they are soft.
- Meanwhile, fill your pressure canner to the 3-quart mark and place it over a high heat.
- Submerge your jars, lids, rings, funnel, ladle, and jar tongs in the canner when the water in the canner reaches at least 180 degrees Fahrenheit but is not quite boiling (a lid caddy is a handy tool for this). If you are preparing a large number of jars, you may sterilize them in the dishwasher and put them in a 220 degree Fahrenheit oven until ready. Keep everything warm until you’re ready to can.
- Remove as many jars, lids, and so forth as you can at once (a 23-quart canner can handle seven quart jars). If desired, include a sprig of basil in each jar. Pour the tomatoes into each jar using the wide-mouth funnel, allowing approximately 1/2″ headroom at the top.
- Insert a clean spatula, knife, or chopstick into the contents and “bubble” it around the perimeter to expel any air bubbles.
- Wipe the jar rims clean with a moist paper towel before placing the lids on top. Screw on the rings until they are finger-tight.
- Close the cover and lower the jars into the canner using tongs.
- Continue to heat over high heat until steam runs freely from the top vent; continue venting for 10 minutes before applying the valve. Continue to cook over high heat while keeping an eye on the pressure.
- Reduce the heat to low and set the timer for 15 minutes when the pressure reaches 11 pounds. Maintain an eye on the pressure: it can get over 11 pounds, but it’s ideal to keep it as constant as possible. Furthermore, if it falls below 11 pounds, it must be hauled back up and the 15-minute timer restarted.
- After 15 minutes, turn off the heat and leave it cool naturally. When the pressure has totally dropped and the cover lock has dropped, open the canner and transfer the cans to the cooling racks using tongs.
- After the jars have cooled for several hours, test them by removing the rings and lifting the jars by the lids. Clean the exterior of the jar.
- The seal did not set if the lids yield. These may be chilled and consumed immediately, or they can be reprocessed and canned.
- Keep it in a dry, dark, and cool area.
In Conclusion, Most common reasons for spoilage in home-canned tomato products are under processing and incomplete seals. Tomatoes that have not been processed long enough to destroy molds and heat-resistant bacteria may spoil during storage. One of the common spoilage organisms, Bacillus coagulans, is very heat resistant and causes flat-sour spoilage. Process times in this fact sheet are designed to ensure the sufficient destruction of bacteria and molds.
Add 2 tablespoons of bottled lemon juice or 1/2 teaspoon of citric acid to whole, mashed, or juiced tomatoes to guarantee acceptable acidity. Freezing is a safe and simple alternative to canning at home. Frozen tomatoes and tomato products do not require the addition of acid.