Homemade Fermented Tomato Ketchup for Full GAPS

This homemade tomato ketchup uses tomato paste, a live homemade starter, cider vinegar, and a small amount of cloves and allspice. Stir the paste and starter together, add the seasonings, and give the jar a two-day room-temperature rest. The vinegar goes in at the end, followed by refrigeration.

The hands-on mixing takes about five minutes. Have your homemade whey or raw fermented vegetable brine ready first. This is a Full GAPS condiment, and it makes about a pint for spooning beside meals or measuring into another recipe.

Jump to the Recipe

Sauerkraut, kimchi, and fermented kimchi hot sauce are already part of our home-ferment routine, and I am still experimenting with more. Condiments fit that same practical corner of the kitchen. I homeschool before leaving for second-shift work, so the useful part is having something ready when I am putting lunch and dinner together. A labeled jar tells me when it started and when it is ready to move into the refrigerator.

Tomato Paste Gives It Body

Start with twelve ounces of organic tomato paste from a glass jar. Look for tomato without sugar, starch, gums, or added preservatives. Salt may already be present, so notice that before choosing your paste.

The paste should be dense enough to hold the mark of a spoon. It is different from tomato juice or a thin tomato sauce. The liquid starter will loosen it, and the vinegar added later brings more liquid as well as a sharp finish.

The recipe allows twelve to fourteen ounces of paste. Twelve ounces is the measured batch in the card. The upper end makes a more concentrated tomato base. Do not replace the paste with the same amount of watery tomato juice and expect the same texture.

Choose Your Homemade Starter

Measure one-third cup of homemade cultured whey. It is the clear liquid drained from completed homemade GAPS yogurt or kefir. The yogurt solids stay in the cloth; the collected liquid is what you use here.

Whey powder, protein powder, and a scoop of yogurt are different ingredients. Use the ready liquid, cool enough that you are not adding culture to hot tomato paste. If your paste was heated, let it cool before mixing.

The same measured amount of raw fermented vegetable brine is another option. Juice from the homemade green sauerkraut can fill that role. Collect it from a completed, unheated batch with a clean utensil and leave the remaining cabbage under its liquid.

The starter affects the flavor. Whey has a mild cultured tang. Sauerkraut brine brings some cabbage flavor and salt with it. Vinegar-pickle liquid is not the fermented brine used for this option.

Keep the Seasonings Measured

Use one-eighth teaspoon ground cloves and one-eighth teaspoon ground allspice. Both are strong in a small jar of ketchup. Measure them rather than shaking freely from the container, and use pure spices without added starch.

Half a teaspoon of natural sea salt seasons the batch. Cayenne is to taste. You can keep the heat mild without changing the measured cloves or allspice.

Three tablespoons of honey are optional. With honey, the tomato has a sweeter finish. Without it, the paste, starter, and vinegar stand out more sharply. It is still the same tomato condiment, but it will not taste as sweet.

Reserve two tablespoons of raw apple cider vinegar for after the room-temperature rest. Sandor Katz’s condiment technique uses live starter in place of vinegar during fermentation. Keeping the vinegar for the finish lets you retain the measured vinegar flavor without putting it into the initial culture mixture.

How to Mix and Rest the Ketchup

Loosen the Tomato Paste

Put the cool paste in a clean glass mixing bowl. Add the measured whey or fermented vegetable brine and work it through with a wooden spoon. Scrape across the bottom and around the sides, where dense paste can remain unmixed.

At first, the liquid may sit around thick red lumps. Keep mixing until it is absorbed into one evenly colored paste. A spoon pulled through it should leave a clear track, with no watery pocket hidden underneath.

Mix in the Spices

Add the cloves, allspice, salt, cayenne, and optional honey. Stir thoroughly, scraping the bowl again. The spices should be dispersed throughout rather than sitting in little dark patches.

Honey can leave glossy streaks before it is fully incorporated. Keep folding and stirring until the texture looks uniform. No electric blender is required for this small batch when you mix it thoroughly by hand.

Give the Jar Room

Transfer the mixture to a clean, wide-mouth glass jar with room above the ketchup. Use a jar larger than the finished amount rather than filling a pint jar to its rim. Wipe the inside walls above the mixture and the rim clean.

Fit a suitable fermentation lid according to its instructions. With an ordinary screw lid, check for pressure and briefly loosen it to release gas if needed, then close it again. The point is to release pressure, not stir air through the ketchup.

Leave at room temperature for two days, out of direct sunlight. Mark the start time on the jar so the two-day rest is easy to follow. Check the jar during that time, including its surface and any pressure under an ordinary lid.

Add the Vinegar and Refrigerate

After the two-day rest, stir in the measured cider vinegar until the ketchup is smooth again. The vinegar adds a sharper aroma and loosens the paste a little. Scrape the sides down and transfer to a clean covered storage jar if needed.

Move the finished ketchup to the refrigerator. Once chilled, it should be thick and spoonable rather than a thin pouring sauce. Keep it cold between uses and take out portions with a clean utensil.

Where It Fits on Full GAPS

This recipe uses tomato, pure spices, cider vinegar, natural salt, and optional honey. Dr. Natasha’s GAPS food guidance allows those foods in their appropriate forms. The whey option also uses cultured dairy, so use it after that dairy food has been introduced.

For a version without a dairy ingredient, choose brine from the linked cabbage-and-salt sauerkraut. Check the actual starter recipe, rather than assuming every vegetable ferment is made without whey.

The complete ketchup belongs with Full GAPS meals. It is not a way to move an early Intro meal forward before its foods have been introduced. Leave the honey out if you are currently avoiding it within your Full GAPS approach.

This tomato-and-spice condiment does not fit No-Plant GAPS. Keep its role small and specific: a spoonful beside a meal or a measured amount in a recipe that calls for ketchup.

Serve and Store the Finished Jar

Serve a little with cooked meat, eggs, or a bunless burger. The egg-free cheeseburger muffins are a separate later Full GAPS recipe you can serve with ketchup, with their own ingredients and introduction notes.

When a casserole or sauce calls for ketchup, measure the finished chilled condiment. One-quarter cup means one-quarter cup of this mixed ketchup, not one-quarter cup of concentrated paste.

After the two-day rest and vinegar finish, keep the ketchup airtight in the refrigerator for up to three months. Freeze extra in small covered portions for up to six months, leaving expansion room in freezer-suitable containers. Thaw in the refrigerator.

Freezing recipe-size portions helps when you want ketchup as an ingredient. Label the amount as well as the date. You can then thaw what the meal needs without repeatedly taking a larger jar in and out of the refrigerator.

Frequently Asked Questions

Can I Use Whey Powder?

Use the live liquid drained from homemade yogurt or kefir. Whey powder and protein concentrates are not that ingredient. Raw liquid from a completed vegetable ferment is the other starter option.

Do I Need to See Bubbles?

Visible activity varies. A thick condiment may not look like a bubbling jar of cabbage. Follow the two-day schedule and check the surface and pressure; do not expect a particular bubble pattern.

Why Is the Vinegar Added Last?

The initial mixture uses the live starter. Vinegar is held back during that rest, then stirred in as the final flavoring before refrigeration.

Can I Leave Out the Honey?

Yes. The three tablespoons are optional. The finished ketchup will taste more tomato-forward and tangy without the sweetness.

Set Up a Useful Condiment Jar

You need a glass mixing bowl, a wooden spoon, a wide-mouth glass jar with headspace, a suitable lid, measuring spoons and cups, and a kitchen scale for the paste. Keep the jar easy to inspect and label its start and refrigeration dates.

The planned Sauces, Dressings & Condiments Cookbook and Crock & Jar: Ferments for GAPS Families course are part of the WFLI catalog. They fit the same kitchen job: making the components before the meal that needs them. Put the ketchup’s two-day rest on the calendar before casserole day.