Wasabi

Wasabi is the spice produced from the rhizomes of Eutrema japonicum, a rare evergreen herb in the mustard family.

REGION OF ORIGIN

Wasabi's roots are firmly planted in Japan, where it grows wild in cool, shaded mountain valleys. Plants found growing on the Korean Peninsula once suggested a wider native range, but recent genetic evidence indicates they are most likely escaped Japanese cultivars rather than a native population.

PART & COLOR

Fresh wasabi rhizomes and wasabi paste have a blend of pale green hues. However, most "wasabi" isn't real wasabi, but rather a mixture of mustard, horseradish, and spinach or green food coloring, resulting in a much darker green. Authentic wasabi rhizomes are either freshly grated, dried and ground into a powder that can be rehydrated, or preserved as a prepared paste. The bright green leaves can also be pickled or eaten fresh as a peppery, bitter salad green.

PRODUCTION

Wasabi is one of the world's hardest crops to cultivate. It requires extremely specific growing conditions: cool temperatures, high humidity, shade, and continual moisture. Learn more about how wasabi is produced.

Fresh wasabi rhizome (Wasabia japonica) standing upright on a metal grater with a pile of freshly grated bright green wasabi paste at its base, with a bowl of sashimi visible in the background

FLAVOR & AROMA

The flavor of freshly grated wasabi is beautifully complex: hot with a bright, natural sweetness. An earthy aroma with hints of fresh grass rounds it out. Unlike the lingering burn of chile peppers, wasabi's heat rushes through the nose with a sharp pungency that quickly fades. This distinctive tingling sensation invigorates and refreshes you as a subtler spice rests on the palate.

It leaves you with a pleasant, cleansing aftertaste that encourages you to take another bite just to relive the ephemeral sensation.

CULINARY USES

In excess, wasabi's fierce heat can overpower its accompaniment (and your sinuses). It is meant to accentuate, so less is more. Rhizomes should be grated as needed because the flavor peaks after two to five minutes.

Wasabi famously highlights the delicate notes of raw fish and complements the saltiness of soy sauce, making it a classic part of the sushi experience. It also amplifies the umami of wagyu and adds an intriguing kick to creamy dips and spreads. Wasabi lends itself perfectly to cold noodle dishes as well, such as udon and soba.

CLASSIFICATION

OTHER NAMES

English: wasabi, Japanese horseradish
French: raifort du Japon
German: japanischer Meerrettich, japanischer Kren
China
- Mandarin: shānkuí, shan kui
- Cantonese: saan kwai
Vietnamese: cải ngựa Nhật Bản
Korean: gochunaengi
Japanese: wasabi, hon-wasabi (true wasabi)

Note: Languages that use only the common international spelling and have no distinct or widely used local name are not listed.

NUTRITION FACTS

FLAVOR CHEMISTRY

Flavor emerges from the combined effects of aroma, taste, and mouthfeel. Wasabi belongs to the same family as mustard and horseradish and shares much of their chemistry, but a distinct compound sets it apart:

Aromatic Compounds

Allyl Isothiocyanate (AITC)
- Wasabi's most abundant isothiocyanate, AITC smells sharply of mustard and horseradish with a sulfurous edge. Since it is highly volatile, it rises straight into the nasal passages, producing the sinus-clearing rush wasabi is known for.
- Sharp, pungent, and sinus-clearing.
6-(Methylsulfinyl)hexyl Isothiocyanate (6-MSITC)
- 6-MSITC is characteristic of true wasabi and far less prominent in mustard and horseradish. Much less pungent than AITC, it layers a fresh, vegetal quality beneath the heat, giving real wasabi a complexity its substitutes lack.
- Fresh, green, and lightly pungent.
Other Isothiocyanates
- Wasabi contains several related compounds in smaller amounts, including 6-(methylthio)hexyl isothiocyanate (6-MTITC), which is especially associated with wasabi's distinctive fresh, green note.

Taste and Mouthfeel Compounds

Isothiocyanates
- The same aromatic compounds above, here for their double role as the source of wasabi's heat. Because AITC is volatile and water-soluble rather than fat-bound, the heat arrives fast, travels through the nose, and vanishes quickly.
- Hot, sharp, and quick-fading.
Glucosinolates
- The odorless precursors stored in the rhizome, glucosinolates are kept apart from the enzyme myrosinase until the tissue is broken. Grating brings them together, and the isothiocyanates form within moments. Sinigrin yields AITC, while glucohesperin yields 6-MSITC. This is a clear example of why many spices exist: defense. Grating wasabi mimics the damage caused by a predator, triggering a chemical response the plant evolved to deter attackers. This also explains why isothiocyanates are antimicrobial. Fortunately, we are large enough to enjoy the result rather than be harmed by it.
- Faintly bitter and pungent.

Understanding Composition

Chemical composition can vary widely, mainly in the concentrations of certain compounds. This variation causes differences in quality, which is why the best spices and herbs are often graded by the levels of key compounds that drive flavor, aroma, and color.
Quality is affected by variety, age and freshness, region and terroir, environmental stressors, and potential adulteration. It's then further influenced by how the plant is handled at every stage: cultivation, harvesting, processing (drying, curing), shipping, storage, and preparation (grinding, grating, infusing, toasting). A magnificent spice or herb is a celebration of an immense journey, shaped by nature, the people who produce it, and the cook who delivers it to a dish.

HEALTH BENEFITS

Wasabi holds intriguing potential health benefits due to its unique chemical composition. The stars of the show are isothiocyanates, which also provide its signature heat. Here is an overview of some of the most promising areas of wasabi's medicinal potential:

Antioxidant and Anti-inflammatory Action
- Wasabi’s compounds have strong indirect antioxidant effects, boosting your body's own defenses against damage from free radicals. They also exhibit anti-inflammatory properties, which could be beneficial for conditions associated with chronic inflammation and joint pain.
Antimicrobial Activity
- Wasabi has been revered for centuries for its antibacterial, antifungal, and antiparasitic properties, traditionally used to combat food poisoning and safeguard raw fish.
Detoxification
- Compounds in wasabi may act on the liver to support natural processes to remove toxic substances from the body.
Weight Loss
- Some preliminary studies demonstrate a role for wasabi compounds in metabolism and fat-burning.
Digestive Aid
- Some of wasabi’s phytochemicals stimulate the secretion of salivary and gastrointestinal digestive enzymes, thereby facilitating smooth digestion and nutrient absorption.
Circulation
- The combined effects of wasabi's powerful antioxidant and anti-inflammatory properties can improve blood flow, although more direct studies are required to verify this with certainty.
Nasal Congestion
- Perhaps most noticeably, wasabi can quickly clear sinuses and alleviate nasal congestion.
Heart Health
- Wasabi's antioxidant action and possible effects on blood pressure and inflammation might positively impact heart health factors. This is still under investigation.
Brain Health
- Some early research points towards wasabi compounds supporting brain function and perhaps even protecting against age-related cognitive decline.
Cancer Protection
- Lab studies suggest that isothiocyanates could suppress cancer cell growth and induce cell death in certain cancer types. More human research is needed for clear impacts.

Important Considerations

Most Research is Preliminary: While research is promising, more extensive human clinical trials are needed to definitively confirm the efficacy and safety of wasabi's medicinal properties.
Dosage Matters: Researchers commonly use concentrated extracts, so standard dietary consumption may not yield the same results. More studies are required to establish proper dosages and administration methods.
Medication Interaction: Wasabi should not be considered a replacement for conventional medical treatments. While it is generally safe for most people, it is critical to exercise moderation and consider interactions with other medications.
Disclaimer: Consult healthcare professionals before using spices or herbs medicinally.

ALTERNATIVE USES

Alongside its stellar culinary and medicinal reputation, wasabi is actively being researched for other interesting applications. Here are some of its popular alternative uses:

Oral Care
- Some toothpastes contain wasabi extracts for their antimicrobial properties, addressing bad breath and protecting against decay. Similarly, certain mouthwashes leverage wasabi's potential to maintain healthier oral flora.
Wound Care
- Antiseptics: Extracts play a small role in some antibacterial soaps and antiseptic solutions.
- Specialized Bandages: Prototype wound dressings include wasabi components, targeting both microbial inhibition and aiding with inflammation and healing.
- Topical Treatments: There is potential in wound healing, antibacterial creams, and addressing specific skin conditions.
Skincare
- Wasabi is being researched for skincare and anti-aging applications due to its antioxidant effects. This includes fighting inflammation linked to premature aging, supporting collagen and elastin, and protecting skin cells from UV damage.
Hair Care
- Studies have shown that certain wasabi compounds (6-MITC and isosaponarin) can stimulate hair regrowth. The practice of rubbing fresh wasabi paste into the scalp has since become a trend in Japan, but further human trials are required for solution refinement.
Supplements
- While more research is needed, supplements tout potential benefits around detox support, allergy reduction, and general antioxidant action.
Smelling Salts
- Inhaling or sniffing wasabi vapor has a similar effect to smelling salts - it wakes you up. Wasabi vapor can thus revive someone who fainted or is feeling lightheaded and dizzy. While this may sound bizarre, researchers have taken this concept to the next level, creating fire alarms for the hearing impaired by determining the ideal concentration of airborne wasabi to get people out of bed in emergencies.
Food Preservative
- Isothiocyanates play a role in keeping food fresher longer by combating spoilage. Researchers are exploring incorporating wasabi extracts into edible coatings or packaging materials to inhibit microbial growth and improve product shelf life.
Air Purification
- Japanese folklore suggests burning wasabi to cleanse the air. While perhaps not as effective as modern practices, this demonstrates an understanding of the sanitizing and odor-eliminating impact of wasabi’s volatile compounds.
Water Purification
- Researchers are studying the ability of certain wasabi components to remove heavy metals and pollutants from water.
Pest Control
- Wasabi is being investigated as a less harsh, natural pest management and crop protection solution. Wasabi has traditionally been used in Japan to discourage rodents and insects from getting into grain storage.

Disclaimer

While wasabi shows promise in these areas, its effectiveness may be limited compared to commercial alternatives.

SUBSTITUTIONS

True wasabi is rarely found outside of Japan because it's so difficult to grow. Unless you’re dining at an exceptional Japanese restaurant that imports fresh wasabi rhizomes or rehydrates pure wasabi paste, that green stuff next to your sushi is a mixture of horseradish, mustard, starch, and green food coloring or spinach powder. So unlike most spices, in the case of wasabi, people are more familiar with the substitute than the spice itself.

Although necessary given wasabi's persistent supply shortage, this fake wasabi has a very different flavor profile—much less complex and enjoyable, and the heat lingers longer. Experiencing freshly grated wasabi rhizome is an evanescent, ethereal wonder. To properly enjoy it, there are a few things you can do:

Visit Japan
- Even in Japan, few restaurants serve real wasabi. Likely only around 5%.
- Location matters. Shizuoka, Nagano, and Iwate Prefectures are some of the top-producing regions and are great places to seek it out.
Source from a specialty Japanese market
- Occasionally, your local Japanese or Asian market may import fresh wasabi. Inquire with them if they do and how often. If not the raw rhizomes, they may carry the freeze-dried powder or the processed paste. Check the ingredients to ensure it’s actually wasabi and not the common substitution mix. Most pastes that say "contains real wasabi" only contain 25-50%, the remainder being filler ingredients that dilute the effect. Due to the food coloring used, most pastes are a darker, earthy green vs. the pale light green of real wasabi.
Source from a high-end sushi restaurant
- Certain sushi chefs have strong supplier relationships in Japan. For a little camaraderie and a nice price, they may let you in on their supply to help out an aspiring cook.
Source from the Pacific Northwest
- Small, dedicated farms are cultivating wasabi along the coasts of Oregon, Washington, and British Columbia. This offers access to the species, but flavor and aroma will be affected by the different terroir and cultivation techniques.

A BRIEF HISTORY

Wasabi's journey from a wild herb to a cultivated plant interwoven into Japanese cuisine is a fascinating story of cultural evolution. Native to the stream beds and mountain river valleys of Japan, wasabi was initially harvested from wild plants for its medicinal properties. It was believed to aid digestion, treat food poisoning, reduce inflammation, and support respiratory health. The first written record of the word “wasabi” was discovered in 2001 on a late 7th-century wooden strip, likely used as a label on a storage container. “Wasabi" is also found in the Honzo Wamyo, Japan's oldest encyclopedia of medicinal plants, written in 918.

In the Edo period (1603-1868), wasabi was cultivated for its appeal as a staple condiment, specifically paired with sushi and sashimi to enhance flavor and safeguard against microbes. This transition marks wasabi's ascent into the culinary world, becoming synonymous with Japanese gastronomy. Tokugawa Ieyasu, the first Tokugawa shōgun whose dynasty ruled Japan throughout the Edo period, was a gourmet. He treasured wasabi for its unique flavor as well as its resemblance to the stylized hollyhock leaves on his family crest. This heightened wasabi’s status and spurred further innovation in its cultivation. The plant is notoriously picky about its growing conditions, so wasabi farming gradually transformed into one of the most esteemed art forms in Japan. Prized for its fleeting heat, sweet freshness, and extreme rarity, a touch of wasabi brought both luxury and vibrant flavor to those fortunate enough to taste it.

The introduction of wasabi to the West was relatively recent, but its impact is undeniable. The global fascination with wasabi speaks to the world's appreciation for the subtleties of Japanese cuisine and the ongoing melding of diverse culinary traditions. Now its distinct zest blesses dishes far beyond the borders of its native country. Yet due to the ongoing difficulty of wasabi cultivation, supply remains tightly constricted. Most of the "wasabi" that people around the world seem to enjoy with their sushi is not wasabi at all, but a mix of horseradish, mustard, and green food coloring. Thus, wasabi's persistent mystique continues to grow with its popularity. To this day, often the best way to experience its elusive allure is to visit its native country and seek out the specific regions that are well-known for wasabi production.

The history of wasabi is not just the story of a single spice’s evolution. It is a window into how cultural and agricultural practices have shaped humanity's relation to the natural world, and how they have grown to connect us all.