Most people grow up learning four basic tastes: sweet, sour, salty, and bitter. But in 1908, Japanese chemist Kikunae Ikeda identified a fifth, distinct taste while studying kombu seaweed broth. He named it umami (旨味) — a Japanese word that translates roughly as "pleasant savory taste" or "deliciousness."

Umami is triggered by glutamate and certain ribonucleotides (particularly inosinate and guanylate) binding to specific taste receptors on the tongue. The sensation is often described as savory, brothy, mouth-coating, and deeply satisfying. It does not fit neatly into any of the other four taste categories — it is its own experience entirely.

Today, umami is widely recognised by food scientists and chefs worldwide. It is present in aged cheeses, cured meats, ripe tomatoes, soy sauce, miso — and, most abundantly in the plant kingdom, in high-grade shade-grown Japanese matcha.

Umami in matcha comes primarily from a family of amino acids and peptides. Unlike glutamate-driven umami in foods like parmesan or soy sauce, matcha's umami is dominated by a unique compound called L-theanine — found almost exclusively in the tea plant (Camellia sinensis) and certain mushrooms.

Why Color Signals Umami

The vivid emerald green color of high-grade matcha is not merely aesthetic. It reflects high chlorophyll content — which, like L-theanine, is produced in abundance under shade-growing conditions. Deep green color and high umami almost always go hand in hand. A dull, yellowish matcha typically signals lower L-theanine levels and weaker umami.

The most important factor in matcha's umami is shade-growing (覆下栽培, kabuse saibai). Tea plants destined for premium matcha are covered with bamboo frames and dark fabric for 3 to 4 weeks before the first spring harvest. This single practice is the foundation of umami in matcha.

• Light is blocked (80–90% reduction): The plant is suddenly deprived of sunlight, which triggers a survival response. It accelerates chlorophyll production to capture every available photon of light.
• L-theanine accumulates: Normally, L-theanine in tea leaves is converted by sunlight into catechins (bitter compounds). With reduced light, this conversion slows dramatically — and L-theanine builds up in the leaf to much higher concentrations.
• Bitterness decreases: Because less L-theanine is being converted to catechins, the leaf becomes naturally sweeter and less bitter. The umami-to-bitterness ratio improves significantly.
• Leaves are harvested at peak umami: Only the youngest, most tender leaves from the first spring flush (一番茶, ichiban-cha) are selected. These first-flush leaves have the highest L-theanine concentration of the entire growing season.
• Tencha is produced & finely milled: After steaming (to halt oxidation), drying, and de-veining, the dried leaf — called tencha — is ground into matcha. Because the entire leaf is consumed, all accumulated L-theanine reaches your cup.

FUJI ASAHIEN's Kawane tea gardens in Shizuoka — where the cool, misty valley climate and expert shade cultivation produce matcha with exceptional umami depth.

Umami can be difficult to describe if you have never consciously identified it before. Unlike sweetness or bitterness, it is not a sharp or immediate sensation — it is more of a presence that develops as you taste.

Umami in matcha is best experienced when you slow down and pay attention. Here is a simple tasting method to help you recognise and appreciate it:

• Prepare correctly: Use water at 70–75°C — not boiling. Hot water over-extracts bitter catechins, which can mask umami. Cooler water preserves and highlights the amino acids responsible for it.
• Sip slowly and let it settle: Take a small sip and hold the matcha in your mouth for a few seconds before swallowing. Notice how the liquid feels — is it light and watery, or does it feel full and coating?
• Look for the coating sensation: High-umami matcha will coat the inside of your mouth with a smooth, slightly silky sensation. This is the L-theanine and amino acids at work.
• Notice the aftertaste (kōki): After swallowing, pay attention to what remains on your palate. A pleasant, savory-sweet warmth that lingers for 30 seconds or longer is the clearest sign of genuine umami.
• Compare grades: The easiest way to understand umami is to taste a Standard grade and a Superior grade side by side. The contrast in richness, depth, and lingering aftertaste makes the difference in umami immediately obvious.

The Role of Preparation Temperature

Water temperature has a profound effect on how much umami you taste. At 70°C, L-theanine and amino acids dissolve freely, while catechin extraction is minimal — resulting in maximum umami with minimum bitterness. At 90–100°C, the balance reverses: catechins dominate, umami recedes, and the cup tastes harsh and flat.

This is why premium matcha should never be prepared with boiling water.

All FUJI ASAHIEN matcha is sourced from the Kawane region of Shizuoka Prefecture — a cool, mountainous valley along the Oi River known for producing teas with exceptional mineral depth and umami character. The three grades differ primarily in the intensity and complexity of their umami.

Fuji-no-Asa offers a light, clean umami — bright and refreshing, with a pleasant vegetal savouriness that makes it an excellent everyday matcha.
Sei-Jaku deepens the experience: its umami is richer and more layered, with a creamy mouthfeel and a satisfying, extended kōki.
Den-sho, FUJI ASAHIEN's Superior grade, represents the full expression of umami — intense, refined, and long-lingering, best appreciated in a traditional bowl as usucha or koicha.

FUJI ASAHIEN's Den-sho served in a traditional ceramic bowl — the deepest expression of matcha umami from Kawane, Shizuoka.