Umami is one of the five basic tastes, along with sweet, sour, bitter, and salty. It is described as a savory, meaty, or brothy taste. Umami comes from glutamate, an amino acid that is found in many foods like meat, fish, dairy, vegetables, and seaweed. Tomatoes do contain natural glutamates, so they can provide an umami flavor.
What is umami?
The term “umami” comes from the Japanese words “uma” meaning delicious and “mi” meaning taste. It was coined in 1908 by Japanese chemist Kikunae Ikeda, who first identified glutamate as the substance that gave foods their savory flavor.
Glutamate is a non-essential amino acid that serves as a neurotransmitter in the human body. When glutamate binds to specialized receptors on our taste buds, it triggers the umami taste sensation. Foods high in glutamate, like parmesan cheese, mushrooms, cured meats, and soy sauce, are therefore described as “umami.”
In addition to glutamate, ribonucleotides like inosinate and guanylate can enhance the intensity of umami flavor when paired with glutamate. This synergistic effect helps explain why ingredients like meat, tomatoes, cheese, and mushrooms all contain compounds that heighten the overall umami taste.
Do tomatoes contain glutamate?
Yes, tomatoes naturally contain glutamate, specifically L-glutamate. In 100 grams of raw tomato there is around 60-290 mg of glutamate.
As tomatoes ripen, the amount of glutamate increases. Fully vine-ripened tomatoes have the highest levels of glutamate compared to commercially-grown unripened tomatoes picked early for shipping purposes.
When tomatoes are cooked or dried, the concentration of glutamate becomes more concentrated as water evaporates. This makes cooked and dried tomatoes even more rich in umami flavor.
Glutamate content in tomatoes vs. other foods
| Food | Glutamate (g/100g) |
|---|---|
| Anchovies | 2.01 |
| Parmesan cheese | 1.47 |
| Soy sauce | 1.12 |
| Tomato juice | 0.42 |
| Mushrooms | 0.32 |
| Raw tomatoes | 0.06-0.29 |
As you can see, while raw tomatoes contain glutamate, they have significantly less than foods like parmesan, soy sauce, or anchovies which are considered very umami-rich ingredients.
What other compounds contribute to umami taste in tomatoes?
In addition to glutamate, tomatoes contain 5′-ribonucleotides that enhance the umami taste sensation:
- Inosinate
- Guanlyate
When glutamate and ribonucleotides are present together, they bind to umami receptors and magnify their effect. This combination results in synergistic umami. 5′-ribonucleotides amplify the taste of glutamate by up to 8 times.
Ripe tomatoes contain about 5-40mg/100g of inosinate and guanylate ribonucleotides. This relatively low concentration contributes to the light umami taste of fresh tomatoes.
However, when tomatoes are dried or cooked into sauces and pastes, the umami flavor gets concentrated along with the glutamate and ribonucleotides.
What other factors influence umami taste in tomatoes?
Aside from inherent glutamate and ribonucleotide content, there are a few other factors that impact how umami tomatoes taste:
1. Ripeness
As tomatoes ripen on the vine, flavors develop and compounds that contribute to umami increase.
Green unripe tomatoes are low in glutamate. At the mature green stage, glutamate starts to accumulate but tomatoes are starchy and acidic.
During ripening, starch turns into sugar, acidity declines, and glutamate levels increase, resulting in the most umami-rich red ripe tomatoes.
2. Variety
Some tomato varieties are naturally richer in umami compounds. Smaller cherry and grape tomatoes often contain higher glutamate levels than standard slicing tomatoes.
Heirloom varieties prized by chefs like Brandywine and Black Krim tend to have greater umami due to being vine-ripened. Mass produced commercial tomatoes bred for uniform shape and shipping tend to be lower in umami.
3. Cultivation method
Tomatoes grown in nutrient-rich soil with proper sunlight develop better umami taste than hydroponic greenhouse tomatoes or tomatoes forced to ripen after picking unripe.
The highest quality tomatoes for umami are locally grown, vine-ripened, and organic. Fast-growing conventional tomatoes often lack the full flavor development of naturally cultivated heirloom varieties.
Cooking techniques that increase umami in tomatoes
While raw ripe tomatoes have a mild glutamate taste, cooking concentrates and enhances their umami flavor.
Cooking techniques that evaporate water like drying, roasting, and sautéing tomatoes draw out more umami. The tomatoes caramelize and their sugars brown for richer flavor.
Slow-cooking or simmering tomatoes for a long time as in stews, sauces, soups, and braises also intensifies umami. Canned tomatoes are quite umami since they are cooked for an extended period.
Blending or crushing tomatoes releases more glutamate and ribonucleotides to interact with umami receptors. Tomato sauces, juices, purees have heightened umami for this reason.
Fermented products like tomato paste contain added umami depth from compounds created by lactic acid bacteria during the fermentation process.
Ways to cook tomatoes for maximum umami
- Oven roasting or broiling
- Sautéing and caramelizing in olive oil
- Simmering in stews, sauces, soups
- Blending into smooth sauces, juices
- Slow cooking in the oven at low heat
- Grilling over an open flame
- Pickling in vinegar
- Dehydrating into sun-dried tomatoes
Pairing tomatoes with umami-boosting ingredients
Since tomatoes alone are low in glutamate compared to other umami foods, they are often combined with ingredients that enhance and amplify their umami taste.
Some classic pairings include:
- Tomatoes + Parmesan cheese
- Tomatoes + Anchovies
- Tomatoes + Mushrooms
- Tomatoes + Worchestershire Sauce
- Tomatoes + Soy Sauce
- Tomatoes + Meat or Fish
- Tomatoes + Garlic
- Tomatoes + Onions
- Tomatoes + Olive Oil
- Tomatoes + Herbs like basil, oregano, thyme
Combining tomatoes with other umami-rich ingredients balances and brings out the umami in the tomatoes through synergism between glutamates and ribonucleotides.
Conclusion
Tomatoes do naturally contain umami compounds like glutamate and ribonucleotides. However, their levels are low in raw ripe tomatoes compared to highly umami ingredients like parmesan and anchovies.
Cooking tomatoes via roasting, simmering in sauces, and other techniques can concentrate and enhance their umami taste. Pairing tomatoes with other umami-bomb ingredients also increases the overall umami flavor.
When evaluating if a tomato is umami-rich, opt for vine-ripened heirloom varieties over unripe standard tomatoes. Look for local in-season tomatoes for the best umami flavor development.
While not the highest in umami by themselves, tomatoes complement other umami foods like cheese, soy, meats to make delicious umami-forward recipes and dishes.