In the ever-evolving world of flavour, few ingredients embody umami as effortlessly as the tomato. Sweet, tart, and seductively savoury, tomatoes hold within their crimson flesh a naturally occurring wealth of glutamic acid, the compound responsible for that deeply satisfying, mouth-filling taste we know as umami. So, what is umami and why are chefs obsessing over it?
Basically, umami is the enigmatic fifth taste, a rich, meaty flavour and a catalyst that unlocks and defines the deliciousness in certain savoury foods. About 3,000 years ago, Greek philosophers came up with the concept of our four elemental tastes: sweet, salty, sour, and bitter. Their theory remained intact right up until the early 20th century, when a scientist in Japan discovered a fifth taste: umami. But unlike the traditional four tastes, umami it seems, is a bit more complicated. In Japan, people have for years used dashi, an umami-rich stock made from kombu (seaweed), to illicit the best flavour from food. The concept of umami has been recognised in the East for a long time, but only over the past decade or so has umami started to play an increasingly important role in the West. Now obsessive chefs believe that if you can find the perfect balance of the five basic tastes: sweet, salt, bitter, sour and umami, you’ll have some sort of culinary utopia!
And in tomatoes, this savouriness is not merely present—it’s central. Ripe, in-season tomatoes, particularly heirloom or vine-ripened varieties, are rich in glutamates, making them powerful culinary tools for creating balance and complexity.
The umami in tomatoes intensifies dramatically with cooking. Roasting, simmering, or reducing tomatoes concentrates their natural sugars and glutamates, transforming the bright acidity of raw fruit into something darker, richer, and far more decadent. It’s what gives a slow-cooked tomato sauce its velvety backbone, or why a simple roasted tomato soup can taste like it took hours to perfect.
I think sun-dried tomatoes have an incredibly intense umami flavour, and there are a number of reasons why the flavour of tomatoes changes during both the cooking and drying processes.
The first is that the tomatoes are sprinkled with fairly high levels of salt to help to remove moisture. During the drying or cooking process this causes all the flavour molecules to become more concentrated. The resulting flavour is more intense and without getting too technical, the glutamic acid breaks down over the course of the drying process - due to the evaporation of water and introduction of salt - and changes into different aroma molecules. That’s why a basic tomato sauce or ketchup has lots of umami, but when you dry tomatoes, they have considerably more and they can also flavour so many dishes. Now is the perfect time to try your own sun- dried tomatoes and unlock all that hidden umami!
The perfect tomato sauce
A well-made tomato sauce is the cornerstone of so many classic, Mediterranean dishes and it’s a really simple and satisfying recipe to make. I’m using “cor de Bou” tomatoes but you could also use plum tomatoes when in season. Don’t be afraid to use tinned tomatoes if you can’t find full flavoured, sun-ripened varieties.
Ingredients:
Serves: 8
- 1kg chopped “cor de bou” tomatoes (skinned and seeded)
- 1 large red onion (finely chopped)
- 100ml olive oil
- 2tbsp sherry vinegar
- 1tbsp sugar
- 3 garlic cloves (crushed)
- 4 torn basil leaves
- 2 bay leaves
- 1 sprig of fresh thyme
- Seasoning
Method
- Sweat the red onion and garlic in a heavy-bottomed pan with the olive oil until they just start to break down.
- Add the chopped tomatoes and cook for 5 minutes.
- Add the sugar, vinegar and herbs and cook slowly for about 30-35 minutes.
- Pass through a fine sieve and season to taste.
Herb-roasted "Cor de Bou" tomatoes
These “meaty” tomatoes are just perfect for roasting but any large beef tomato will suffice.
Ingredients
Serves 4
- 4 “Cor de bou” tomatoes
- 25 basil leaves
- 12 sprigs thyme
- A bunch of chopped chives
- Olive oil, for drizzling
- Sea salt and cracked black pepper
Method
- Preheat the oven to 180°C (355°F).
- Remove the stalk from the tomatoes to create a small cavity and cut 2 slashes on each side. Push the basil leaves and thyme sprigs into the cavity and the slashes . Place on a baking tray, drizzle with olive oil and sprinkle generously with the salt and pepper. Bake for about 25-30 minutes. To serve, carefully place the tomatoes in a bowl and drizzle with fresh olive oil and the cooking juices from the pan. Garnish with chopped chives and fresh basil leaves.
Oven "sun-dried" tomatoes
Almost an indispensible ingredient in my kitchen, tomatoes actually take on an intense umami flavour when they are dried and add a really tasty kick to so many Mediterranean recipes.
Ingredients:
- 2kg ripe plum tomatoes
- 6 garlic cloves, crushed
- 4tbsp chopped oregano
- 2tbsp chopped rosemary
- 1tbsp sea salt (flor de sal)
- Freshly ground black pepper
- Extra virgin olive oil
Method
- Preheat the oven to the lowest heat setting.
- Slice the plum tomatoes in half horizontally and scoop out most of the seeds. Salt the insides and turn the cut side down on a wire cooling rack- leave for half an hour, then rinse and dry.
- Mix the crushed garlic with the oregano, rosemary and black pepper. Sprinkle this mixture over the cut side of the tomatoes.
- Place the tomatoes cut side up on a wire rack over a roasting tray and dribble with olive oil.
- Place in the oven for 6-8 hours.
- Place the tomatoes in a sterilized kilner jar and cover with extra virgin oil.
- Store in a cool, dark place for no longer than 6 months. Refrigerate upon opening and keep for 1 month covered with olive oil.
Sun dried tomato pesto
*Pesto rosso is a variation on traditional green pesto. The addition of sundried tomatoes gives it a distinctive, milder flavor. Try it with pasta, smeared on bruschetta or brush it on a chicken before roasting.
Ingredients
- 2 cloves of garlic, peeled
- 100ml olive oil
- 150g sundried tomatoes
- 1tbsp pine nuts
- 2tbsp freshly grated Parmesan cheese
- A twist of black pepper
Method
- Place all the ingredients except the oil into the container of a food processor; blend and gradually add the oil with the processor running on high speed.
- Store the pesto in a tightly closed jar in the fridge.