Equipment
Ingredients
Vegetable Base
- 1500 g roma tomatoes, roughly chopped
- 150 g yellow onion, chopped
- 15 g garlic, crushed
Seasonings and Preservatives
- 120 ml apple cider vinegar
- 80 g brown sugar
- 10 g salt
- 3 g mustard powder
- 2 g celery salt
- 1 g ground allspice
- 1 g ground cloves
- 2 g black pepper, freshly ground
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 21 kcal
- Protein
- 1 g
- Carbohydrates
- 5 g
- Fat
- 0 g
- Fiber
- 1 g
- Sugar
- 4 g
- Sodium
- 121 mg
- Saturated Fat
- 0 g
- Monounsaturated Fat
- 0 g
- Polyunsaturated Fat
- 0 g
- Potassium
- 122 mg
- Calcium
- 10 mg
- Iron
- 0.2 mg
- Magnesium
- 7 mg
- Phosphorus
- 14 mg
- Zinc
- 0.1 mg
- Vitamin A
- 0 mcg
- Vitamin C
- 7 mg
- Vitamin E
- 0.0 mg
- Vitamin K
- 0 mcg
- Vitamin B6
- 0.0 mg
- Niacin
- 0.0 mg
- Folate
- 1 mcg
- Water
- 4 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Place the chopped tomatoes, onion, and garlic in a heavy-bottomed pot over medium heat. Bring to a gentle bubbling simmer.
Reduce the heat to medium-low. Cover the pot and cook until all the vegetables are completely soft and breaking down, stirring occasionally to prevent sticking.
Remove the pot from the heat. Using an immersion blender, blend the vegetable mixture until it is as smooth as possible. If using a countertop blender, blend in batches and be careful with the hot liquid.
Pour the pureed mixture through a fine mesh sieve into a clean bowl, using a ladle or spatula to press the liquid through. Discard the skins and seeds left in the sieve.
Return the smooth tomato puree to the rinsed pot. Add the apple cider vinegar, brown sugar, salt, mustard powder, celery salt, ground allspice, ground cloves, and black pepper. Stir well to combine.
Place the pot over low heat. Simmer gently, uncovered, stirring frequently. Continue to cook until the mixture reduces by about half and thickens to a ketchup consistency. Be careful as the thick mixture may splatter. A temperature of around 90C/195F should be maintained.
Remove from heat and let the ketchup cool to room temperature. Transfer to sterilized glass jars and refrigerate.
Chef's Notes
- Tomato varieties matter significantly here. Roma, San Marzano, or Amish Paste tomatoes have lower water content and higher pectin, resulting in a thicker ketchup in less time.
- The spices used here form a classic flavor profile, but ketchup is highly adaptable. Consider adding a pinch of cayenne pepper for heat or smoked paprika for a barbecue-style flavor.
- Constant stirring during the final stages of reduction is crucial. Because of the high sugar content from the tomatoes and added brown sugar, the bottom can scorch quickly once it thickens.
- For the smoothest texture, a high-powered blender is vastly superior to an immersion blender, though the sieve step is still strictly necessary to remove the seeds.
Storage
Refrigerator: 1 month — Store in a tightly sealed sterilized jar.
Freezer: 6 months — Freeze in an airtight container leaving room for expansion.
Troubleshooting
Water bleeds out from the ketchup when plated
Cause: The ketchup was not reduced enough, leaving too much free water
Fix: Return to the pot and simmer on low heat for an additional 15 to 20 minutes until thicker
Prevention: Ensure you perform the chilled plate test before removing from heat
Ketchup has a gritty or chunky texture
Cause: Ineffective straining or blending
Fix: Pass the finished ketchup through a fine mesh sieve again before it cools completely
Prevention: Use a finer mesh sieve and thoroughly press the mixture through to remove all skins and seeds
Ketchup tastes too acidic
Cause: Tomatoes lacked natural sweetness or vinegar has not mellowed
Fix: Stir in an additional 10g to 20g of brown sugar and simmer for 5 more minutes to dissolve
Prevention: Use very ripe, in-season tomatoes
Cultural Context
While modern ketchup is heavily associated with American fast food and diners, its origins lie in early Chinese fermented fish sauces called ke-tsiap. It evolved through British colonial adaptations involving mushrooms and walnuts before the first tomato-based recipes appeared in America in the early 19th century. Today, American tomato ketchup is defined by its careful balance of sweet, sour, salty, and umami flavors.
