I knew this. I knew this. I'd made a batch of homemade tomato ketchup years and years ago in Spokane and learned just how very, very long it takes to cook down. (Why specify "tomato" ketchup? Because, as I learned from The Joy of Cooking, whether you call it ketchup or catsup it's any savory smooth vegetable sauce. Mushroom Ketchup? It's a thing.)
But oops, I did it again. Had a lot of green tomatoes and remembered last year's idea of making green tomato ketchup. I'd even rounded up the recipes. And I still have plenty of my beloved green tomato chutney on hand, supplemented by some green tomato/tomatillo chutney that's a bit sharper, but still good.
Last year I tried making the dehydrated seasoned green tomatoes linked in that same post. Blech. And we'd been saying we'd like to have ketchup on hand without ever actually getting around to buying any. I can fix this!
Sunday I headed out to the yard to pick the many, many green tomatoes left and do a bit of cleanup of the raised beds. Since I started my seed snail 'speriment a bit late, the Mortgage Lifter heirloom tomatoes hadn't had enough time to ripen. They're huge and beautiful and I'll be starting those seeds earlier in 2026 so I get the payoff in ripe red tomatoes.
So, yeah, around 24 pounds or so of green tomatoes.
Brilliant idea: Make batches of three different recipes in a head to head taste contest, then use the last batch of tomatoes to double down on the winner.
Dear Reader, this is not how I'll ever spend another Sunday.
I got through two of the three recipes. Neither of them makes my heart beat faster. One was the winner with Sweet Hubs. Fortunately, that was the batch that had more tomatoes based on the recipe's proportions. I added more sugar to both recipes. Neither of them is a giftable product, which is my yardstick for success.
And the labor! So many steps. So many. The two recipes used two different approaches, too.
Mamta's Kitchen Green Tomato Ketchup: Cook the tomatoes, onions and garlic until soft, which didn't take nearly as long as the four-hour Creative Canning recipe. Put through a food mill, then through a sieve to get the smooth sauce consistency, then cook with spices, vinegar and sugar. This batch had a smaller quantity of tomatoes. I doubled it to 2 kg and was able to fit into my deep saucepan. I normally wouldn't double an untried recipe but I had so, so many green tomatoes and the spice mix sounded really good. Garam masala, mustard, and more.
The recipe indicated that 1 kg of tomatoes would produce around 2 liters of sauce before adding spices etc. My tomatoes must have been super juicy, as I started with 2 kg and ended up with not quite that 2-liter mark. I seasoned based on volume produced, not volume I started with. I added more spices after tasting; mine are getting old, I know.
Yield from all of that: 2 half-pints, 1 quarter-pint.
Creative Canning Green Tomato Ketchup: Cook everything everywhere all at once for a long, long time (four hours), stirring frequently so it doesn't stick to the bottom of the pan. This started with 6 pounds of tomatoes so I used my Dutch oven. I'd already done the food mill + sieve steps for the Mamta recipe. This one called for pureeing ingredients in a blender, then putting it through a sieve. Much easier than the (manual) food mill process. I'd started with more tomatoes so it isn't a completely parallel comparison but I know I threw a lot more tomato skins/seeds/solids into the compost with Mamta's recipe than with this one.
This one was sweetened with honey. I added another cup of sugar after tasting (one-half cup at a time). It came out the flavor winner and was a much brighter green color.
Yield: 6 half-pints.
If I were making either of these again, which I will not be doing, I'd use the blender + sieve technique from Creative Canning. I might use the cooking approach from Mamta's because it was so much faster, but then again that might be a function of the tomato quantity.
I couldn't tell you whether having the seasonings in from the beginning can be credited with the better flavor of the Creative Canning approach. I'd actually think it would be the opposite because seasonings added too early can disappear a bit. Mamta's recipe made the point that sugar and salt both darken the end result, hence adding them in at the end, but the spice profile with several brown spices and blends meant hers was the darker brown sauce anyway.
Another lesson learned: I had purchased cute little 8-ounce stout bottles from Fillmore Container, planning to bottle whatever sauces I might make this year as a change of pace from chutney. But the ketchup was thick enough that it wouldn't pour easily out of the bottle and I realized it would be far easier to can it in my standard jars. I'll use those bottles for something runnier.
In a side note, I couldn't find instructions for headspace with that smaller mouth, which worries me. Need enough air to suck out for the vacuum, not something that creates so much pressure the bottle gives way in the kettle. The functional headspace with a much smaller circumference is obviously less so I think I need to do the geometry calculation to figure out how much headspace yields the equivalent air volume of a 1/4" headspace on a regular mouth jar. I'll keep poking around to find that or do the math before I try making some other sauce.
I did the prep for the third batch while the others were cooking down. I'd always known it would have to wait, given the amount of time it takes ketchup to cook down. So I whirled the tomatoes and onions in the food processor and stuck them in the fridge.
Know what I'm going to make with them instead of the third ketchup recipe?
Chutney.
Related reading and recipes
- When Life Hands You a Defrosted Freezer, Make Jam
- My Circular Economy of Apples
- Making Taybarb: Tayberry Rhubarb Jam Recipe
- Canstravaganza! Food Preservation 2024
- Blackberry Apple Chutney Recipe
- Green Tomatoes. So Many Green Tomatoes.
- Apples, Apples, Apples!
- Zucchini Tomato Salsa (Everyone Needs Salsa, or, What to Do with a Really Giant Zucchini)
- Tomatoes, Tomatoes, Tomatoes!
- Pears, Pears, Pears!
- Future Marmalade
- All my posts on food, gardening, and the environment
