How to Make Fermented Ketchup

Whether you are on the GAPS diet or simply moving toward clean eating, having a simple, quick, and tasty ketchup to turn to is always a good idea. Bonus points when your ketchup is a gut healthy, probiotic rich, fermented food! Great on burgers. in salad dressings and sauces, with roasted veggies or fries, or any other way you typically use ketchup, you will find this fermented ketchup easy and pleasing, even to kids.

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When we start trying to eat really nourishing, clean food, ketchup might not be the first problem we try to solve. Most of us start with vegetables, quality meat, eggs, and dairy, or reducing processed foods and sugars. Or, especially for anyone embarking on the GAPS diet, we might think about the foods we want to add, like meat stock and fermented foods.

But ketchup? Really, how much ketchup will anyone eat at a time?

Well, if you know anyone like my older son, ketchup could come close to being its own food group. At least when he was younger… He used to call it “ketch” with great fondness.

For many children, ketchup is weirdly addictive. At least, the popularity of ketchup is a little weird to me. Maybe it is the sugar? Whatever it is, a lot of people love ketchup. It can be a little incentive for getting some kids to eat something they aren’t interested in, and it can be used in many recipes.

The problem is, most ketchups from the store just aren’t that great for us health-wise. A little here and there may not be that big a deal for most people. But what about those who, like my son, use a lot on very many foods? Also, what about when you are going to do GAPS?

Most store brands are just not going to work. They usually have corn syrup, “natural flavors”, and sometimes worse. Some are made with cane sugar in place of the corn syrup, but it is quite a lot of sugar in there. As in, there may be about a teaspoon of sugar in one tablespoon of ketchup. Not bad if you eat a tablespoon now and then, but lots of people like a more generous helping, and eat it frequently.

There are reduced sugar versions, and sugar free versions, and even date or honey sweetened versions out there. Some can get pretty pricey. Many come in tiny bottles, and some versions have other downsides, like sugar substitutes.

Then, if you do something like the GAPS diet where sugar and fake sugar are totally out, ketchup might seem like another favorite that you’ll just have to forgo for the duration. Such bad news for our dear ketchup lovers.

There is a solution– and it is easy and cheap!

You don’t have to nix the ketchup! Good news, especially if you are trying to coax kids to eat differently. Or adults, for that matter. Some adults will be happier with ketchup on the menu, too.

Even more good news: your ketchup can be an asset to your nutritional efforts! Not only do the tomatoes have their own benefits, but you can ferment the ketchup so that you are serving probiotics every time you pull out the fermented ketchup. I like to try to serve some probiotic food with every meal. I mostly fall short, but we eat them at least daily.

Yet more good news: this fermented ketchup recipe is very easy and fast to prepare using kitchen staples you can easily keep on hand (and probably have right now). Once you know how you like to adjust the spices, you can make a bunch at once; it lasts a really long time due to the fermentation. I think the longest I have ever had it in the refrigerator was a few weeks.

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Some Interesting Tidbits about Ketchup

• The name came from Chinese (“ge-thcup” or “koe-cheup”). The ancient Chinese were also fermenting it, making it transportable on sea voyages.
• The Chinese were writing about their ketchup as long ago as 300 B.C. Theirs was made from things like fish entrails, soybeans, and meat products not otherwise useful. Admirably thrifty and resourceful, if somewhat less than appetizing to the modern Western taste.
• As the Chinese took their ketchup through the Pacific on their voyages, they eventually crossed paths with British mariners, who took the idea and sailed back to England with it.
• The British made ketchups with assorted seafoods, mushrooms, nuts, and other fruits and vegetables, plus LOTS of salt. According to this article, Jane Austen liked the mushroom version. At least that sounds better than the fish gut type.
• Tomato-based ketchup came around in the 1800s in the United States, with Heinz glass bottles of ketchup coming out in 1876. Remember the glass bottle that wouldn’t let the ketchup out while you pounded the bottom until a great dollop splooshed out all over the place? Well, at least you could see what was in the bottle, and know it wasn’t fish guts or something…

Health Benefits of Fermented Ketchup

• some amount of vitamins A,C, K, and some of the B vitamins, potassium, and copper
• antioxidants
• lycopene (cardiovascular, skin, and other benefits)
• probiotics (if you ferment it)
• no weird ingredients and nothing you don’t want to include!

Are there downsides to this recipe?

There could be. If you don’t tolerate nightshades well, you won’t want the intense dose of tomato. Tomato paste is pretty concentrated. In that case, you could try a beet ketchup. It looks different and sounds funny, but it actually tastes OK.

Yes, I tried beet ketchup once (not the linked recipe, but similar). It was for my ketchup-loving, food-averse toddler when we thought maybe he was getting a rash from ketchup. He loved the beet kind, too, but we went back to tomato once we determined the tomatoes weren’t the problem.

Another problem might be if you are sensitive to probiotics. Some people have trouble with them at first, especially people with SIBO or a lot of other gut damage. If you haven’t been consuming much probiotic-rich food, it is wise to start with small servings and just one new one at a time. Work up slowly if you are doing fine with it, and add only one new fermented food or drink at once.

If you can’t do ferments yet, you can make this recipe and not ferment it. It works fine that way. Many times I have made a batch, used some that day for a recipe, and fermented the rest.

Does fermented ketchup taste weird because it’s… fermented?

There is a weirdness factor for many of us who didn’t grow up eating fermented foods. Yogurt from the store seems sort of sanitized (and isn’t nearly as beneficial as the home made kind!), and some people are now familiar with kombucha (also rather wimpy in the store bought form), but home fermented foods and drinks can seem a little icky at first. It’s a good thing to get over!

I can’t tell this fermented ketchup is fermented. It tastes different from the store versions because it is less sweet. I also include more seasonings than the store brands, and make it thicker, but you wouldn’t have to do that. Sweetness and spice are customizable, so taste and adjust until you like it.

Same for the thickness– tomato paste is very thick, so you will thin it some as you add the honey, vinegar, and whey. You can add more or less whey to make it more or less thick. Once you have the recommended amount of whey, you can add water if it is still too thick to suit you.

The tomato taste is a bit more intense than store ketchup, probably because we start with tomato paste. You could use partly tomato sauce if you prefer. Then you would need to add less liquid.

There isn’t any bubbly aspect, and fermented ketchup isn’t noticeably tangier after fermenting than before. The tang you would expect from tomatoes and vinegar is there, but nothing like the tanginess of something like sauerkraut.

Do I have to ferment it?

No, you don’t! I like to ferment it for a few days for the gut health benefits, but it isn’t necessary. I often make it and use a bit that day while fermenting the rest. If I am planning to cook the ketchup anyway (like in a sauce), this seems just fine! The fermentation benefits are mostly lost in cooking. I can’t tell the difference between fermented and fresh, actually.

If I were making a whole batch and not intending to ferment, I might just use water in place of the whey. The whey helps get the fermentation process going. If you don’t want to ferment the ketchup, the whey is not necessary.

Can I make this recipe if I can’t use whey?

Yes, you can! If you are allergic to dairy, or don’t have whey, or whatever your reason, you could substitute another probiotic rich liquid for the whey.

I typically collect whey when I am working with my own cultured dairy projects. Sometimes I make yogurt, then put it all in a flour sack towel (cheesecloth also works) and let the whey drip out, leaving a thicker yogurt similar to Greek yogurt from the store.

Another source of whey is kefir cheese making. I sometimes do the same process as the yogurt with kefir. If it drips long enough, the part left in the towel is very thick, like cream cheese. The whey left behind is wonderfully nourishing, and an ideal starter culture.

If you don’t plan to use whey, you have some options. Sauerkraut juice, or the juice from other fermented vegetables, will work. That is what I used while I had a dairy-allergic family member. It will be saltier, so you may want to reduce the salt in the recipe.

Kombucha or water kefir (unflavored!) would be other alternatives. These would be very easy to use, and I have used kombucha back in our milk allergy days.

Liquid from nondairy yogurt should work, though I have not tried it. I never seemed to get much liquid when I used to make coconut milk yogurt, but if you have this sort of thing, use it!

It would likely also work to stir in a powdered probiotic, like from a starter culture or a probiotic capsule. I have not tried that, though. Let me know if you do!

How to Make Fermented Ketchup

1. Measure your spices and tomato paste. (Ideally, you would use freshly made tomato paste or the kind from a glass jar. We don’t all live in an ideal world, and the kind from cans will do just fine. I do this, even though I prefer the glass jar type. Budgets are real. If you make your own, you should get a prize!) Whisk the spices into the tomato paste.

2. Whisk in your apple cider vinegar, honey, and whey.

3. Adjust the ketchup to your liking. Add more seasonings if you like, and add more whey or some filtered water to make it thinner if you like. I find that the taste and the thickness don’t change during fermentation, so get it the way you want it now. Pour the ketchup into 2 pint jars, cover them, and let them sit at room temperature for 1-3 days. Store in the refrigerator after that.

Make It Your Way

• Substitute another probiotic liquid for the whey. I have used kombucha and juice from sauerkraut and fermented carrots successfully. Plain water kefir or liquid from a nondairy, cultured yogurt would likely also work, as would a powdered probiotic.
• Start with lower spice measurements, especially if you like things milder. Add more as needed to suit your taste.
• The chili powder is an outlier in this recipe; I have tried several ketchup recipes, and read many more. None called for chili powder. I like it. But you could leave it out!
• On the contrary, many ketchup recipes call for a teaspoon or less of either fish sauce or soy sauce (or coconut aminos). You could try these. They taste good in ketchup, but use just enough so that you can’t really tell what is in it. We aren’t making stir fry sauce! If you use just a touch, the taste will be more complex but nobody will know exactly why!
• Increase or reduce the honey. This is a matter of taste and how much honey you are willing to consume.

There are so many uses for fermented ketchup! Salad dressings, sauces, serving with savory dishes– but there is nothing like ketchup and a good burger!

There you go! Easy, gut healthy ketchup that is budget and GAPS friendly! What are your favorite uses for ketchup?

Want more ideas for fermented foods? Try probiotic lemonade, root beer water kefir, GAPS vanilla ice cream, or cultured chocolate ice cream!