5 Ways to Preserve Tomatoes 🍅

Today I’m going to share with you five recipes on how to preserve tomatoes and take their summer freshness into winter. Some of them are really easy, some more complicated, but all truly delicious.

It’s loads of work and at the same time lot of fun to have a vegetable garden. I enjoy watching huge plants growing from tiny seeds. It is the best way to eat according to the season and the freshest veggies ever.

Each year around January I start to search through seed catalogues, as I love to experiment with new plants but there are also quite a few veggies that I plant year and year on, like tomatoes for instance.

I just cannot imagine not having them around – I even had a few on the balcony in containers when we lived in a condominium. They are delicious, they come in all sizes, shapes and many colors. Moreover, they are really easy to care for also for self-taught gardeners like me. I’ve been planting them for so many years now that they are actually growing by themselves from seeds hiding in the soil from previous years without planting. II’s hard for me to discard wildly grown tomato plants, therefore - technically speaking - each year I end up with a tomato forest with huge plants, many of them 2.5 meters tall.

Direct consequence is that every year there comes a time when I have to ask myself the question what I’m gonna do with the abundance of tomatoes coming from my plants? Over the years I tried a number of recipes for preserving them, I’d like to share my favorites:

1. Oven-dried tomatoes in olive oil

2. Fermented cherry tomatoes

3. Tomato paste

4. Tomato jam

5. Tomato powder

Let's get started! You'll find ingredients and tools at the start of each recipe.

Step 1: Sterilizing Jars - the Easy Way

As some of these recipes call for sterilized jar, let's start with this, before diving into the recipes.

There are many ways to sterilize jars, I like to take it simple.

1. Place jars, lids and rings into a large pot.

2. Fill it up with water so that it covers jars.

3. Bring it to a boil and boil for 10 minutes. Allow them to rest in hot water until ready to use.

4. Very carefully, just before filling them, use a tong to remove jars and lids and place them upside down on a clean kitchen towel.

Step 2: 1. Oven-dried Tomatoes in Olive Oil

Traditionally these are made by placing tomatoes in the sun for several days depending on the temperature and humidity, but I find it more practical to use the oven at low setting (or a food dehydrator).

If you have the chance, I strongly suggest to give them a try. They are absolutely tasty with their concentrated tomato flavor, each a tomato flavor bomb, really. Eat them as they are, bake them into bread, grissini, put on pasta … so many uses.

What is important is to chose tomato types that are more fleshy than juicy (eg. Lucullus, Roma) as practically what we are doing is slowly extracting fluid and we don’t want to be left with only the skin.

The idea is to dry them to the consistency you like, then you can either put them in a jar, cover with olive oil and keep it in the fridge for up to 1 month, or you might as well freeze them laid flat and then transferred into a freezer bag (in this case it is safe to eat for at least 6 months).

You’ll need:

Ingredients:

• tomatoes (quantity is up to you, I used 40-45 pieces of small plum tomatoes to fill an oven rack)
• salt
• pepper
• thyme (optional, feel free to use your favorite herb or garlic)
• olive oil (optional, depending on the choice of preservation method, see above)

Tools:

• Oven rack
• parchment paper
• cutting board
• knife
• spoon
• cup

Step 3: Prepping Tomatoes

1. Wash tomatoes and remove stalks.

2. Cut in half lengthwise.

3. Scoop seeds and juice out with a teaspoon.*

4. Remove pith.

* Juice may be freezed and used when cooking ragout or stew.

Step 4: Bake Them

1. Place tomatoes cut side up on an oven rack lined with parchment.

2. Set the oven at the lowest setting (mine was 50 degrees Celsius).

3. Sprinkle with salt and pepper, drizzle approximately with 2 tablespoons of olive oil.

4. Bake for roughly 2.5 - 4 hours until tomatoes reach the desired dryness. Baking time is strongly dependent upon the liquid content of the tomatoes, the oven and how dry you want them, so I can't be more precise than that. Keep an eye on it after the first 2 hours.

5. When you think that it's almost ready, add herbs and put them back into the oven for another half an hour or so.

Step 5: Storage

There are two ways to store them.

1. In olive oil as seen in the photos.

• Transfer tomatoes into a clean jar,
• fill the jar with extra virgin olive oil so that it totally covers the tomatoes.
• Keep it in the fridge for up to 1 month.

(Olive oil left over may be used as salad dressing.)

2. Freeze

• Line them up on a tray covered with parchment that fits into your freezer,
• freeze them hard,
• transfer them into freezer bags and store in the freezer.
• They are safe to eat for at least 6 months.

Step 6: 2. Fermented Cherry Tomatoes

It may be surprising, but you can not only ferment cabbage, cucumbers, but also tomatoes. This is a great way of preserving cherry tomatoes for later. As for the outcome: softish tomatoes, bursting as you eat them, full of flavor. that can be just picked at or used on top of pasta, risotto, or to accompany meat. Delicious!

Apart from being delicious, consumption of fermented food is generally considered to be beneficial for your guts.

Fermentation takes place in brine, as a rule of thumb 2-3% salt content brine shall be used (calculated in the ratio of the weight of veggies and water altogether).

It is very important to keep everything submerged in brine, to achieve this I always use some neutral flavored veggie that I tuck under the neck of the jar to stop veggies / herbs rising above water level.

What happens during fermentation?

Microorganisms (bacteria, yeast or fungi) to be found on the surface of the veggies on your hands etc. break down organic compounds – such as sugars and starch – and convert them into alcohol or acids. Starches and sugars in vegetables are converted to lactic acid which acts as a natural preservative.

Ingredients:

• cherry tomatoes [370 g]*
• salt [17 g]
• water [295 g]
• 1 slice pepper / celery stalk per jar
• herbs (optional, I used basil and garlic chives) [2 sprigs of fresh basil, 2 garlic chive leaves]
• garlic (optional) [1 clove]
• 2 small fresh grape leaves per jar (it is said to promote crispyness, but as for the two bottles I 've made so far it seems to be a myth)

Tools

• digital scale
• calculator
• clean screw-lid jar(s) [720 ml]

* Note:

All quantities given in square brackets are my measures and shall be considered as indicative. Exact quantities depend on the jar you're using and the size and shape of tomatoes (how well you manage to stack them, how much empty space remains in between). Don't bother measuring exact quantities beforehand, gather the ingredients, follow instructions, measure along the way and work with your own measurements as described later on in detail.

Step 7: Prepping

1. Boil water and let it cool to room temperature.

2. Wash your tomatoes and remove stalks.

3. Wash herbs and clean garlic.

Step 8: Filling the Jar

1. Place the jar you're using on a digital scale. Set the scale to "0" so that after putting everything in, it will show the exact weight of everything inside (but not the jar).

2. Place herbs and garlic into the bottom of the jar.

3. Fill the jar with tomatoes up until the neck.

4. Tuck a slice of pepper / celery stick under the neck of the jar at both ends in order to prevent tomatoes from floating.

5. Pour boiled and cooled water over so that everything is submerged.

Step 9: Calculation Time

Now you need to calculate the amount of salt needed. I went with 2.5 mass percentage. The amount of salt is to be calculated by multiplying the total weight of veggies and water in the jar by 0,025 (2,5%).

To put theory into practice, in my case, as you can see in the previous step (last photo) that the total content of the jar weighed 687 g. Simple math coming up: 687 x 2,5% = 17.175, that is the amount of salt (in grams) that must be added.

The way to do it:

• scoop 3-5 tablespoons of water out of the jar into a microwave proof cup, then
• heat this small amount of water in the microwave (to help salt dissolve),
• place the cup with the water on the scale and set it to "0" (we only want to measure the quantity of the salt),
• add the calculated amount of salt and stir until dissolved (my scale automatically switched off by the time I grabbed my phone to take the photo, so you just have to believe me that I added 17 g of salt into the water),
• pour the salty water back into the jar.

Step 10: Finishing Touches

Put the lid on the jar, not too tight, as there will be bubbling and gas formation in the next days, so there should be some gap for excess liquid and gas to leave the jar. If you can move the lid with just your thumb and forefinger, you're good.

Place a small plate underneath (as mentioned above, part of the brine may escape) and leave it on the counter for a week. Afterwards, secure the lid and keep it in the fridge for up to 6 months. (Fermentation will continue but at a much slower pace due to low temperature.)

Sometimes things go wrong...

I've been fermenting various vegetables for over a year now, and it happened to me only once: if you see mold on the surface of your fermented food when opening the jar, throw the whole thing out. Mold may occur due to various reasons like not proper salt ratio, veggies not completely submerged in brine. Don't hesitate, just get rid of the whole jar.

Step 11: 3. Tomato Paste

You could definitely say that tomato paste is available in any supermarket, so why bother making it?

Firstly, because home-made tomato paste is a lot more delicious, and also, if you have an abundance of tomatoes it is a very practical and since the paste itself amounts to about 10% of the original weight of tomatoes used, a most certainly space - saving way to make use of them.

As I use tomato paste in many different style dishes, I like to keep the paste itself simple (no strong spices, no herbs) and do the seasoning when cooking with it.

What type of tomatoes shall be used?

Honestly, any. But bear in mind that making the paste is basically reducing the quantity of tomato juice by boiling, so it is more practical to chose meaty, paste tomatoes (Roma, San Marzano) they provide for a larger amount.

As for storage, you have two options:

1. Process in hot water bath/steam oven. (If you are planning to keep the tomato paste in jars, start by sterilizing the jars as detailed in step 1.)

2. Freeze in ice cube trays.

You’ll need

Ingredients:

• 2 kg tomatoes
• ½ teaspoon salt
• 1/3 teaspoon pepper
• ½ teaspoon citric acid (only necessary if processed in jars)

Tools:

• large, thick bottomed pot
• cutting board
• knife
• wooden spoon
• food mill / food strainer
• ice cube tray + Ziploc bag / 120 ml sterilized jar

Step 12: Prepping Tomatoes

Wash tomatoes, cut larger ones in smaller pieces, remove stalks and pith.

You may leave smaller cherry tomatoes in whole.

Dump all in a large, thick bottomed pot.

Step 13: Cooking

Start cooking at low heat, switch to medium heat when part of the liquid has been released from the tomatoes sitting in the bottom (pic. 2.). Cook until soft.

Step 14: Processing

Pass the tomatoes through a fruit strainer or a food mill to separate pulp from seeds and skins. I like to scrape the pulp from the "I-have-no-idea-about-the-name-of-the strainer-part" into the juice (pic.3.).

Seeds and peels may be composted, or even better, turned into delicious tomato powder.

Step 15: More Cooking

Simmer the tomato juice in a large, thick bottomed pot until reduced to a paste (4-6 hours, depending on the juiciness of tomatoes, and the size of the pot – the wider it is, the faster reduction takes place).

Don't forget to stir occasionally. When the sauce gets thick, close to being ready I suggest to keep an eye on it constantly.

The paste is ready when it is shiny, there should not be any moisture separating from the paste.

Step 16: Storage

If you wish to go the easy way round, fill the paste into ice cream tray(s). Freeze completely, then transfer into Ziploc bags.

An other option for preserving:

Put 1/2 teaspoon citric acid into the bottom of the jar, scoop the paste over and close tightly, Turn it upside down to stand on the lid for 10 minutes.

Process in boiling water bath for 20 minutes or use steam oven for sterilizing - in this case follow oven manufacturer's manual.

Step 17: 4. Tomato Jam

Tomato jam is simply irresistible. Sweet and spicy at the same time, can be eaten for example on top of a toast or with cheese.

You’ll need

Ingredients:

• 1.2 kg tomatoes (mostly meaty types like Roma or San Marzano)
• 2 x 500 g cherry tomatoes
• 250 g sugar
• 50 g honey
• 60 g lemon juice
• 2 teaspoons ginger (fresh or powder)
• ½ teaspoon salt
• 1 teaspoon chili flakes
• 1 star anis
• ½ teaspoon ground black pepper
• 2 tablespoon pectin (may be omitted, in that case your jam will set less firm)
• 1/2 teaspoon citric acid per jar

Tools:

• Digital scale
• thick-bottomed pot
• food mill / fruit strainer
• hand blender
• sterilized jars (with the above quantities I ended up with 2 x 250 ml and 2 x 130 ml jam, but it may vary depending on the juiciness of tomatoes used)

Step 18: Prepping

1. Sterilize your jars (see step 1.).

2. Wash tomatoes, cut, remove stalks and pith of the larger ones, small one may be added in whole.

3. Dump tomatoes into a large, thick bottomed pot.

Step 19: Cooking and Processing

Start cooking on low heat, then raise heat to medium when some of the juice of the tomatoes have been released. Cook until soft.

Then with a food mill or a fruit strainer separate pulp from skins and seeds. The latter may be discarded / composted / used to make tomato powder.

Step 20: Spice It Up and Keep Cooking

Put the pot back to cook. Add sugar, honey, lemon juice, ginger, salt, chili flakes, star anis and black pepper (ie. everything save for the 2 x 500 g cherry tomatoes and pectin, if using).

Simmer until it reaches a thick-jam like consistency.

Step 21: Adding Cherry Tomatoes

For me, thick tomato skins can be very disturbing, this is why I prefer to get rid of them. However, no matter what type of jam we're talking about, I like the fruity bits in it, this is where cherry tomatoes with their more delicate skins come into the picture.

When your tomato jam reached the jam - like consistency add the first batch of 500 g cherry tomatoes (cut in half, or in whole, does not matter) and keep cooking. When they are soft, blend them with a hand blender and simmer again until it reaches jam-like consistency.

When you get to this point, add the second 500 g batch of cherry tomatoes and cook until they are soft. This time, no blending, just press some of them against the side of the pot with the spoon while stirring to break down.

Simmer until it reaches jam-like consistency (I know, again...), mix in pectin and cook for 3 more minutes. Done.

Step 22: Storage

Put 1/2 teaspoon citric acid into the bottom of each sterilized jar.

Ladle the jam into jars up to the rim, secure lids.

Turn jars upside down to stand on the lids for 10 minutes.

Process in boiling water bath for 20 minutes or use steam oven for sterilizing - in this case follow oven manufacturer's instructions.

It is shelf-stable for 12 months.

Step 23: Tomato Powder

Do you remember the seeds and skins separated when making tomato paste or jam? This is an easy way to make use of it. Though you might as well make tomato powder from thinly sliced and dried tomatoes. The result is an easy - to - store, shelf- stable flavor booster you can add for example to soups, stews.

You'll need:

• tomato skins and seeds (by-product of making paste / jam) or sliced thinly tomatoes
• salt
• baking tray
• parchment paper
• food processor / coffee grinder
• jar to store

Step 24: Dry

Spread tomato skins and seeds on a baking tray lined with parchment.

Set the oven to the lowest setting possible (50 degrees Celsius in my case).

Let them dry until crunchy. It may take 3-8 hours depending on oven temperature and how juicy the tomato bits were.

Check every hour, then when it starts to get close, every 20 minutes. Turn pieces upside down after 2-3 hours in the oven to help even drying.

Step 25: Grind

When tomato pieces are completely dry, place them into a food processor with a teaspoon of salt added to each batch. Salt helps grinding, it is not really for the taste. Grind as fine as you wish, then transfer into jars.

Step 26: Before and After

Have fun in making and enjoying the result of your work!