It’s easy to preserve your home grown tomatoes as tomato sauce (as it is known here in Australia – also known as tomato ketchup in other countries).
Yield: 14 cups
Tomatoes, Roma*
11kg (24 pounds)
Onion, Diced
3 cups
Apple Cider Vinegar (minimum 5% acidity)
3 cups
Sugar (optional)
1 cup
Salt, Finely Ground (optional)
3 tablespoons
*Other “paste/plum” tomato varieties can be used - they are dense with less seeds and are long or pear shaped. Some examples include Amish paste, black prince, Italian gold, opalka, Polish linguisa, principe borghese, san marzano, saucy and sausage.

1.  Clean jars and equipment by washing in hot soapy water and rinsing well before use.
NOTE: Only 500ml (2 cup/pint or smaller in volume) are suitable for this recipe.
2.  Wash tomatoes. Discard spoiled tomatoes (damaged tomatoes will affect the flavour, reduce storage period and increase risk of spoilage). Remove tomato cores.
3.  Spread tomatoes on an oven tray in a single layer. Do not add any oil. Roast tomato trays on low heat until tomato skins split open.
4.  Remove trays from the oven and cool tomatoes to touch.
5.  Discard tomato skins (skins can be set aside to dehydrate into tomato powder)
6.  Combine peeled tomatoes and diced onion in a large pan and boil gently (uncovered) for 20 minutes.
7.  Puree tomato/onion mixture i.e. blender/food processor.
8.  Press tomato/onion mixture through a food mill (or sieve) to discard seeds.
9.  Combine tomato puree, vinegar, sugar (if using) and salt (if using) in a large pan. Boil gently for around 30 minutes, until reduced by half in volume (or thickened to your liking).
10.  When the tomato sauce is ready: place the lids into a heatproof bowl and cover the lids with boiling water. Remove the lids from the water when you are ready to place them onto the jars to seal.  
11.  Place jars onto a heatproof surface i.e. wood board (or tea towel).
12.  Fill jars with hot tomato sauce, filling to 0.5cm (1/4 inch) from the rim of each jar.
TIP: use a jar funnel to fill jars.
13.  Using a non-metal utensil (i.e. chopstick), remove any bubbles and add more hot tomato sauce if required to correct the headspace if it dropped below 0.5cm (1/4 inch) from the jar rim.
14.  Wipe jar rims with a damp paper towel to remove any food residue.
15.  Remove lids from hot water and seal jars i.e. twist to secure “fingertip tight”.
16.  Place jars of tomato sauce into the pot of boiling water and boil for the processing time stated below. Start the timer once the water comes back to a full boil.
17.  Turn off the heat source once the time is up. Remove jars from hot water after 5 more minutes. Cool jars overnight on a heatproof surface i.e. wooden board or towel. Do not adjust lids during this time.
18.  After 12-24 hours: check jars have sealed before labelling and dating clearly.
19.  Store jars of tomato sauce in a cool, dark and dry place (i.e. pantry) for up to 12 months. Jar lids should remain tightly sealed during storage, and not flex up or down when pressed (which indicates jar seal failure, do not consume).
20.  Refrigerate jars upon opening and consume contents within 3 weeks.
TIP: Freeze leftover tomato sauce from opened jars in freezer safe containers.
Processing Time for  TOMATO SAUCE (TOMATO KETCHUP)  in a Boiling Water Canner

Altitude Processing Times
Packing Style
Jar Size
0-1000 ft
1001-3000 ft
3001-6000 ft
6000+ ft
Hot Pack
500ml (2 cups/pint) or smaller
15 minutes
20 minutes
20 minutes
25 minutes
o  Spices can be added to this recipe i.e. allspice, celery seed, chilli, cinnamon and cloves;
o  Sugar is optional for this recipe – leave out completely, or reduce the quantity listed above.

Bottled tomato sauce, cold-smoked cheese and dehydrated herbs from the garden.

Yum yum yum!
Sweet potato toast for dinner tonight! Topped with sautéed spinach, a buttery fried egg, smoked tomato sauce and garlic salt
Author: Megan Radaich          
Image Credit: Megan Radaich          
Kaya Wanjoo. Food Preserving kaditj kalyakoorl moondang-ak kaaradj midi boodjar-ak nyininy, yakka wer waabiny, Noongar moort. Ngala kaditj baalap kalyakoorl nidja boodjar wer kep kaaradjiny, baalap moorditj nidja yaakiny-ak wer moorditj moort wer kaditj Birdiya wer yeyi.
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