Homemade Low FODMAP Ketchup

Things are about to get SAUCY my friend! Once you try this easy homemade low FODMAP ketchup you'll never buy another bottle of Heinz again, (who just confirmed to me by email that the flavourings in their secret recipe contain garlic and onions!).

Making your own ketchup is much easier than you might think. The recipe below can be completed in less than 30 minutes. The great thing about homemade tomato sauce is being able to tailor the sugar, salt and spice to suit you.

This simple homemade version tastes better than ANYTHING I've ever splodged out of a shop-bought bottle. And the secret sauce is that it's a total game-changer when it comes to eating, and more importantly, enjoying, all those low FODMAP potatoes.

Call me feral but if it's not covered in ketchup there's a 50/50 chance that I'm not interested in putting it in my mouth….

Smutty office jokes aside, ketchup on a low FODMAP diet can be a bit of a tricky subject. Although it seems like a fairly generic flavour that we're all familiar with, the ways that different manufacturers, in different countries, create that same flavour varies quite a lot.

Speaking of differences, before we go any further I'll start by pointing out that we're talking about tomato ketchup, aka tomato sauce, aka red sauce, aka catsup, aka tommy sauce. The red stuff, most often dolloped on chips and burgers.

I make this distinction only because from the original 17th-century version up to the 21st-century recipe that we recognise today, ketchup looked VERY different from what we're used to. Ingredients such as salted or pickled fish, cochineal (insects that create a red colour when dried and crushed!), shellfish, egg whites and mushrooms have all been historically used.

Thankfully, those are not the types of ingredients we need to worry about today, but as low fodmappers, there are still plenty of things lurking in there that we potentially need to avoid. Luckily this recipe has you and your fries covered.

Ingredients

To make this tomato ketchup you will need:

• Garlic-infused oil to fry the spices and add a hint of FODMAP free garlic flavour.
• Tomato puree for a rich, deep tomato flavour and a thick smooth sauce.
• Balsamic vinegar for that lip-smacking tang. Any vinegar can be used, but I love the complex sweetness and depth of colour that balsamic brings to this recipe.
• Dried cloves, ground cinnamon, brown sugar, salt and black pepper to cut through the acidity of the tomato puree and give the signature warm and sweet ketchup aroma.
• Asafoetida to replace the allium flavour of onions and garlic typically used to flavour commercial ketchup.
• Chilli powder is optional but I like the hint of spice. Check that your powder is true ground chilli and is not blended with other ingredients such as onion or garlic powder.
• Filtered water. I always use filtered tap water in my recipes. Depending on the quality of drinking water where you live, unfiltered water can negatively affect the final taste of a recipe. This especially applies to recipes such as sauces, soups and stews where the water stays within the recipe rather than something like boiling vegetables or pasta where the water is drained away.

See the recipe card below for quantities and the detailed FODMAP ingredient notes for low FODMAP portions and considerations.

Instructions

1. Heat the oil in a nonstick pan on medium heat for 30 seconds. Add the cloves and sprinkle the asafoetida evenly across the surface of the oil. This keeps as much of the asafoetida in contact with the oil as possible which helps to temper the pungent spice.

2. Add the cinnamon and the chilli powder. Stir briskly for 30 seconds, keep the spices moving around in the oil to prevent them from burning.

Tip: Turn on the extractor fan and open a window before you start. The spices smell fierce when frying and can cause eye-watering coughing fits if you don't have adequate ventilation.

3. Turn the heat to low and quickly stir the tomato puree into the seasoned oil. Keep it moving around the pan to avoid sticking and burning.

4. Add half of the water and stir well. Once the puree is fully incorporated into a thick, smooth sauce add the balsamic vinegar and stir again.

5. Sprinkle over the sugar, salt and black pepper and stir continuously until the sugar fully melts.

6. Stir in half of the remaining water, the sauce should look thick and glossy.

7. Allow the sauce to come to a gentle boil then turn the heat as low as it can go. Simmer gently for 20 minutes, stirring frequently throughout.

Tip: Cover the pan with a vented lid. Even on the lowest setting the sauce splatters everywhere. Be careful not to get splashed with hot sauce each time you remove the lid to stir.

8. After 10 minutes, add the remaining water if you think the sauce has thickened too much. I used a total of 250 ml/1 cup of water to get the desired thickness.

You may not need to use all of the water, especially if you cover the pan with a well-fitting lid. Condensation trapped in the lid can help to thin the sauce without needing to add the remaining water.

9. Once you're happy with the thickness and depth of flavour of the sauce turn off the heat. I simmered mine for a total of 20 minutes. You can simmer for up to an hour but you will need to occasionally add more water as the sauce thickens.

Tip: Don't forget to remove the whole cloves from the sauce before bottling it up.

10. Allow the sauce to cool for 10 minutes off the heat so that it's safe to handle. It's easier to bottle up or portion out the sauce if you pour it into a heat-safe glass jug first.

11. Carefully pour the warm sauce through a funnel into sterilised glass jars. Once cooled seal with a well-fitting lid. This ketchup will store in the coldest part of the fridge (towards the back not in the door) for up to 2 weeks.

Shake the bottle before each use.

Note: This recipe and bottling method are not suitable for long-term preservation or ambient shelf storage.

12. Alternatively, dispense the sauce into smaller portions and freeze.

You can do this in single-tablespoon portions in ice cube trays or a few portions at a time in small containers. Once frozen, dispense the portions out of the plastic containers and into a freezer-safe glass container.

I do not recommend storing acidic, tomato-based sauces in plastic for an extended amount of time.

Recipe Video

Substitutions

• Onion - If you don't need this ketchup to be low FODMAP then swap the asafoetida with ¼ teaspoon of onion powder and ¼ teaspoon of garlic powder.
• Sugar - swap the brown sugar for an equal amount of white or palm sugar if preferred. Coconut and demerara sugar have much smaller low FODMAP servings and will add a small amount of extra FODMAPs to the overall recipe.

Serving suggestions

I honestly have no shame in stirring this through pasta or rice, purely in an attempt to avoid wasting it of course. For a more conventional pairing try it with my crispy baked hash browns.

This ketchup also makes the perfect base for my homemade BBQ sauce. Use half of it in my smoky BBQ sauce recipe so you have two delicious sauces to alternate between.

Ketchup in the Monash app

This is where you would usually pop into the Monash app and see what they have to say and it's here that things get a bit more complicated. Depending on whether you have the app set to filter by country or not, you may see some different results. The good news is that they seem to agree that 13 g or 2 regular sachets, roughly 2.5 teaspoons, is a low FODMAP portion. Let's break it down a bit:

Monash app set to UK filter

Ketchup is listed in the Monash app under generic tomato sauce and has a low FODMAP serving of 13 g. Unfortunately, they don't state which brands were tested and what ingredients they contained. They do tell us that at just 26 g it becomes moderate for fructans. Ketchup in the UK is much more likely to be flavoured with sugar/sucrose rather than high fructose corn syrup.

Monash app set to US filter

Ketchup sweetened with sugar/sucrose is listed as low FODMAP at 13 g or 1 sachet (perhaps US sachets are bigger than UK sachets?). It becomes moderate for fructans at 20 g and high for fructans at 26 g.

Ketchup sweetened with high fructose corn syrup is considered low FODMAP at 13g or 1 sachet. It becomes moderate for fructans at 19g and high for fructans at 26g

Monash app set to Australia filter

Strangely, there are non-specified when filters are set to Australia. If searching for ketchup only branded versions, approved by Monash, are shown. Searching for tomato sauce brings up the same generic listing that shows for the UK or when no location filters are set.

If you're unsure about the FODMAP levels of the ketchup you buy then test it by sticking to the generic low FODMAP portion of 13 g to see how you react.

Recipe FAQ's

Which brands of ketchup are low FODMAP?

If the idea of making ketchup does not appeal to you then you'll be pleased to hear there are premade low FODMAP brands available.

Unfortunately, most brands of ketchup you can find in the supermarket such as Heinz, Daddies, HP, Hellmann's, shop's own label and even artisanal, high-end brands are often high FODMAP or simply reluctant to disclose which flavourings and spices are used.

To find a safe, certified brand of low FODMAP ketchup you'll need to shop around online, usually at a specialised low FODMAP supermarket. Although I haven't personally tried these I've heard good things about these particular brands:

• FODY tomato ketchup (332 g). This popular brand is available internationally and is certified low FODMAP by Monash University. It lists sugar as the second ingredient so if you're looking for a sweeter sauce, closer to regular ketchup, then this might hit the spot.
• Bays Kitchen tomato ketchup with sundried tomatoes (270 g). This brand is certified gluten and dairy free. It's also certified low FODMAP in 20 g portions by FODMAP Friendly.
• Frusano organic tomato ketchup (345 g). Frusano is a dedicated low fructose brand, creating products that are low FODMAP and lower in fructose than their regular versions.

* We use affiliate links here to help support our work. Purchasing through these links does not affect your consumer rights or the price you pay but may result in The Irritable Vegan receiving a small commission payment. We thank you for supporting us in this way whilst you shop.

Cooks notes

The longer you cook this the more intense the flavour becomes. I was happy with mine after 20 minutes but you could let it bubble away very gently for up to an hour. Just be aware that the longer you cook, the thicker it gets, so you'll need to add more water as you go.

This ketchup is rich and tangy. It's much closer in taste to a naturally sweetened or low salt/low sugar variety rather than a standard ketchup. Feel free to increase the salt and sugar levels to suit your tastebuds.

Most commercially prepared ketchups list sugar as the second ingredient and in my opinion are overly, sickeningly sweet. This ketchup uses a much higher percentage of tomato puree and a lower percentage of sugar which may give a more acidic result than you're used to.

Storage & food safety

This is not a canning recipe for tomato ketchup and is not suitable for long-term preservation or room-temperature shelf storage.

The recipe below makes 450ml, roughly 30 servings at 1 tablespoon each. If you don't use ketchup on everything, or you're not making this for a family, then you'll either need to halve the recipe or be prepared to freeze it in smaller batches so it doesn't spoil.

This sauce freezes really well. Even if you're the only one eating it I would stick to the quantities here so you have plenty pre-made when you need it.

Depending on how regularly you eat ketchup, I recommend dividing the sauce into five portions of 90ml. Keep one jar in the coldest part of the fridge (towards the back and not in the door) and this ketchup will store for up to two weeks. You can then freeze the rest. Leave the top ¼ of each jar empty to allow for expansion as it freezes. Freeze for up to 6 months. Thaw overnight in the fridge and shake well before using.

Alternatively, freeze single portions in ice cube trays. You'll need to remember to defrost each portion before use which might get a bit irritating if you tend to forget as I do. You could always defrost it in the microwave in a pinch.

FODMAP Notes

This recipe was edited in August 2022 to reflect the changes in the Monash app to the low FODMAP serving size and FODMAP category of tomato puree/tomato paste. The recommended serving size of this recipe has been reduced to 1 tablespoon.

Whilst this recipe remains low FODMAP up to a maximum of 5 Tbsp, at this amount it contains one full portion of fructose. Depending on what you'll be serving with it, you can decide if you want to eat a full portion of fructose in ketchup alone. This will depend on the chances of how that might FODMAP stack with the rest of the meal.

FODMAP Servings

As written this recipe is low FODMAP in 1 tablespoon serving. Each 1 tablespoon portion contains approx:

• 0 Fructan
• 0 GOS
• 0 Mannitol
• 0 Sorbitol serving
• 0.22 Fructose serving
• 0 Lactose - All my recipes are vegan and therefore free from dairy and lactose. Yay!

Please refer to the FODMAP ingredient notes below regarding the FODMAPs in tomato puree versus tomato paste.

* Always refer to the Monash app for current low FODMAP serves and FODMAP categorisations.

FODMAP Ingredient Notes

Asafoetida

In this recipe, the distinct, allium aroma of asafoetida is used to replace the typical onion and garlic flavourings used in traditional ketchup.

Some varieties may contain wheat flour. If this is an issue for you then source the pure version or wheat-free brands. The brand I use is Schwartz, which is blended with rice flour. If using pure asafoetida or undiluted Indian hing reduce the recipe amount by at least half until you get used to the intensity of your purchased brand.

Balsamic vinegar

Low FODMAP serving of 1 Tbsp. At a serving size of 2 Tbsps, it becomes moderate for excess fructose. In this recipe, we're splitting 2 tablespoons between 30 servings which brings it well below the low fodmap serving for fructose.

Brown sugar

Low FODMAP serving of 40g or ¼ cup. In this recipe, we use a total of 2 tablespoons shared between 30 servings. This takes us way under a low FODMAP serving.

Many people are confused about sugar being included as a low FODMAP ingredient. The reason sugar (sucrose) is usually well tolerated is that it is made up of equal parts fructose and equal parts glucose. The presence of an equal or higher percentage of glucose helps our bodies to absorb and digest fructose. When we avoid fructose on a low FODMAP diet we only need to worry about those foods which contain an excess of fructose, in comparison to glucose.

Unfortunately, many artificial sweeteners, those ending in 'ol' and many natural sweeteners such as dates, applesauce and overripe bananas are all incredibly high FODMAP.

Chilli powder

Low FODMAP serving of 2g or 1 tsp. Ensure your powder is pure ground chillies. Some supermarket brands are blended with other spices and may contain onion or garlic. Brands I have found to be pure chilli include Rajah, East End and Natco.

Some people may have non-FODMAP reactions to the capsaicin content of chilli. This can trigger flushing, heartburn and stomach pain. Reduce or omit depending on your tolerance.

Garlic oil

Infused garlic oil, (free from visible garlic pieces) is FODMAP safe. Pure oils are free from carbohydrates which makes them naturally FODMAP free.

Some people with IBS may have non-FODMAP reactions to oil. If you prefer you may omit the oil and water saute your ingredients instead. Bear in mind that omitting garlic oil from a recipe will affect the finished flavour. You may wish to add ginger, asafoetida, spring onion greens, leek green tips, or chives to compensate for the lack of garlic flavour.

Tomato puree/paste

In the 2022 Monash app update tomato puree was added as a separate listing when previously only tomato paste was listed. This is likely to cause some confusion as the two appear to contain different FODMAP types.

Here in the UK, we tend to refer to this thick, concentrated tomato ingredient as tomato puree and it usually comes in metal, squeezy tubes (see ingredient photo above). However, my US friends typically refer to the same ingredient as tomato paste and it's more often found in small cans.

Having used both the puree in tubes and the paste in cans I cannot see any discernible difference. But, in the absence of any further clarification from Monash, depending on where you live and what you call it the portion sizes and FODMAPs may differ.

Tomato puree has a low FODMAP portion of 36 grams or 2 tablespoons. It becomes moderate for fructose at 48 grams and high for fructose at 50 grams. In this recipe, we use a total of 200 grams. When split between the recommended 30 servings of a single tablespoon each serving contains only 6.6 grams of puree which equals 0.22 servings of fructose.

Tomato paste has a low FODMAP serving of 28 grams or 2 tablespoons. It becomes moderate for fructans in servings of 81 grams and high for fructans at 85 grams. Previously no excess FODMAPs were listed. In this recipe, using 200 grams of tomato paste split between 30 servings, each serving will contain 0.23 servings of fructans.

This means that depending on which listing you feel best describes the product that you use, either puree or paste, the FODMAPs in this recipe will change. If using tomato paste your ketchup would be predominantly fructan-containing, rather than fructose-containing as the FODMAP servings suggest.

Shopping Tips

• Schwartz asafoetida (52 g) This is the brand I usually buy from the supermarket. It's widely available, affordable and blended with rice flour which makes it a good choice for the low FODMAP diet. Buying asafoetida online can be a tricky business. Many online suppliers do not specify the ingredients and could be blended with wheat flour or otherwise contaminated or unsuitable for those avoiding wheat and gluten. Check out this video I created all about buying and cooking with asafoetida.
• FODY garlic-infused extra virgin olive oil (250ml). If you're worried about using garlic oil then this brand is officially low FODMAP certified by Monash. Unfortunately, as with any niche-branded product, you'll pay a premium for the peace of mind that comes with certification. When purchasing regular garlic oil look for the words "infused" and make sure the oil is clear and free from any visible garlic cloves, pieces or sediment.

* We use affiliate links here to help support our work. Purchasing through these links does not affect your consumer rights or the price you pay but may result in The Irritable Vegan receiving a small commission payment. We thank you for supporting us in this way whilst you shop.