Wasabi, common name of the Japanese plant Wasabia japonica (山葵) is also known as Japanese radish. Usually, in the kitchen, both the leaves and the root are used . The former are dried and used as a spice to flavor dishes. Otherwise, the root is used to obtain a very dense pulp with known digestive and medicinal properties .
The taste of wasabi paste is certainly very particular and this aspect makes it very popular but also unwelcome. However, the fact remains that its properties make it a real functional food, that is, a food useful for obtaining a good state of health. This is due to the richness in isothiocyanates , which guarantee infinite qualities capable of bringing benefits to the body of those who consume it.
The root of wasabi is very expensive and is considered among the most expensive vegetables in the world. Just think that a single root of average size can cost about € 220 per kilo . But pay attention to the common sophistications on the market.
Wasabi: what it is and difference between plant and sauce
It is a plant native to the island of Sakhalin and probably also widespread in China, although very rare.
The wasabi belongs to the Brassicaceae family, which is the same of many very common plants in our latitudes such as horseradish, mustard but also cabbage and Brussels sprouts, cabbage, broccoli and broccoli.
It is a very slow growing shrub plant, known and used, in the kitchen and beyond, since ancient times.
Difference between plant and wasabi sauce
The name wasabi is usually used to describe both the plant and the paste that is obtained by grating the rhizome.
In fact, a very rich paste is obtained in substances containing sulfur , known as isothiocyanates and known for their antimicrobial properties. The appearance of the wasabi paste looks truly harmless but you shouldn’t be fooled.
In fact, isothiocyanates give it a particular taste and a high spiciness.
Why wasabi is so spicy
The intense spiciness is the basis of a second common name by which wasabi is known, or ‘namida’.
In Japanese, this term means tear as excessive consumption of this paste can cause very intense tearing.
This could make it seem similar to chilli but, in reality, the mechanism of action is very different from that of the bright red counterpart. In fact, chilli, and in particular the active ingredient known as capsaicin, acts on receptors in the mouth. The effect is intense spiciness on the tongue but the absence of tearing.
On the contrary, wasabi isothiocyanates act on the mucosa of the oro-nasal tract . For this reason, lacrimation can be a side effect of a possible abuse of this pasta in the kitchen.
How to make wasabi
The making of this pasta is particularly complex although the main difficulties are almost exclusively related to finding the necessary raw materials.
In fact, the cultivation of the plant up to the correct state of ripeness (as well as obtaining a rhizome useful for the purpose) is very complex. The plant needs very specific microclimatic conditions and soil types .
In addition, the rhizome grows extremely slowly, requiring years before it can be exploited in order to obtain a good wasabi paste. What if we decide to get a nice and ready rhizome? The difficulty would not be less as it is really difficult to find it on the market . All combined with a very high purchase price.
Just think that 100g of fresh rhizome can cost as much as 70 euros !!!
With good reason, it is possible to say that this rhizome is a real vegetable ‘ jewel’ . Finally, watch out for falsifications. In fact, it is easy to come across manipulations of the rhizome marketed at lower prices but not classifiable as ‘original ‘ wasabi .
Ingredients necessary for the preparation of the pasta
Nothing could be simpler … the ingredient is only one, that is the root. There is also only one tool to use, that is a grater, even better if made with a wooden board with the handle covered with ray skin (as per ancient Japanese tradition).
In fact, the natural roughness of the skin of the breed is able to guarantee the correct consistency of this highly prized pasta.
Processing process starting from the fresh root
Once the necessary material to obtain this renowned pasta has been collected, the production process is really simple. If you start from a ‘dirty’ root, i.e. with the leaves, you must remove the latter. The leaves are not necessarily thrown away … we can reuse them in the preparation of a fresh salad or dry them and use them as spices.
The root must always be well washed and dried.
In fact, by washing it we make sure to eliminate all the dirt while correct drying is essential to prevent it from rotting. Once this is done, we are ready to use the grater , obtaining the very compact wasabi paste, in the shape of a ‘ball’.
The pasta obtained must be left to rest for about 10 minutes before consuming it . In this way we guarantee the final product to have all the desired palatability characteristics. Be careful not to wait too long because, in this case, we would risk losing some of the properties of the wasabi .
Processing process starting from the dry root
In this case, water and wasabi root powder must be mixed in equal parts. Only in this way can you obtain a pasta of the right consistency and taste. Be careful not to touch your eyes with dry wasabi dirty hands … in addition to the burning sensation on your tongue, you risk remembering that in your eyes too!
Wasabi: nutritional values
Wasabi is rich in vitamin A, B vitamins (B1, B5, B9) and vitamin C. In addition, microelements abound such as:
Wasabi: properties and health benefits
The three isothiocyanates most present in wasabi are:
- 6-methylthiohexyl isothiocyanate
- 7-methylthioeptyl isothiocyanate
- 8-methylthioctyl isothiocyanate.
These are molecules with a strong antimicrobial action. This aspect is able to give wasabi important bactericidal properties .
First of all, this virtue allows wasabi to protect against the risk of food poisoning related to the consumption of raw fish , to which it is often combined.
Pain relieving action
This ongoing quest for wasabi consumption has led many researchers to investigate a possible cause. Recently, a work published in the US journal Proceedings of the national academy of sciences ( PNAS ) highlighted an incontrovertible truth.
That is, consuming wasabi regularly would seem able to perform a pain relieving action.
This seems to be due to the action that the molecules of which the pasta is rich, could have on the inactivation of a receptor, known as (Trpa1), involved in the transmission of the painful impulse.
It is believed that the regular consumption of minimal portions of wasabi can help to carry out an antibacterial disinfectant action in the mouth. In this way, it can promote dental health by reducing the proliferation of bacteria in the oral cavity, which are responsible for many diseases also affecting the teeth.
Hence, it is a real anticaries cure-all!
This property is closely linked to the presence of vitamin C . In fact, ascorbic acid is able to carry out a disinfectant action against many microorganisms.
This makes for an optimal combination of wasabi with raw fish , common in Japanese cuisine.
It is even believed that this property may be one of the secrets of Japanese longevity.
Wasabi has many molecules capable of acting as precursors of phytochemicals.
The latter, in turn, can assist the liver in carrying out a detoxifying action , expelling toxins and helping to cleanse the liver itself.
This property is strictly connected with the purifying one.
In ensuring proper liver function , wasabi would also seem to facilitate the elimination of certain carcinogens.
So, the result of this could be a preventive intervention, even before they can harm the body, triggering the tumor.
We have previously seen that isothiocyanates act directly on the mucous membrane of the oro-nasal passages .
It is believed that this aspect can be a real cure-all for the respiratory tract , especially in case of colds.
The Japanese tradition includes, among the thousand virtues of wasabi, also the aphrodisiac one. It is thought that its consumption may be able to promote erection as well as sexual drive . The latter not only in man but also in woman .
It would seem that the molecules contained in wasabi are able to ensure the maintenance of calcium in the bones .
This aspect would be fundamental to prevent the risk of osteoporosis . However, more scientific studies will have to confirm this theory.
Storage of wasabi
The flavor and spiciness typical of wasabi paste are easily perishable.
For this reason, the root should be consumed a maximum of 10 minutes after grating it, so that it retains a stronger flavor.
Alternatively, it can be stored in the refrigerator for 1-2 days as long as it is stored in an airtight container. Despite this precaution, it will be impossible to prevent the loss of part of its flavor .
In fact, after this time, the pasta will lose its special properties becoming excessively ‘delicate’!
Wasabi: buying guide
In Japan, real wasabi is called hon-wasabi (本 山葵), a term that means “original wasabi”.
To overcome the difficulty of finding this food delicacy, the market has found an ideologically invalid stratagem.
In fact, when you buy ready-made wasabi paste , it is often actually horseradish paste or a mixture of extracts from several plants.
The most common pastes on the market contain Armoracia rusticana , or Armoracia Lapthifolia or Cholearia Arnoracia , mustard seeds and FDA approved dyes .
In a nutshell, it cannot be called wasabi but it would be more correct to call it European horseradish, colored and with added mustard seeds!
This pasta actually has a much lower taste and spiciness and would have a yellowish color. Then, to make them take on the typical green color, the pasta is colored with spirulina algae powder.
Uses in the kitchen
Commonly wasabi is paired with raw fish dishes.
This association is not accidental, like most of the combinations (food and otherwise) of the oriental tradition.
In fact, the renowned antimicrobial and antibacterial properties of wasabi make it suitable, I would say almost fundamental, in the combination with raw fish.
It is no coincidence that it manages to partially attenuate the smell of fish but also the possible food poisoning deriving from its consumption.
Contrary to what one might think, even if less common, the consumption of the fresh root is still possible . In fact, small portions of the wasabi rhizome can be included in sushi along with rice and fish as well as in Hosomaki or Nigiri .
It is useless to repeat further how this pasta can find traditional use combined with fish, both fresh and in the form of pasta.
On the contrary, very few know that wasabi paste can also be the basis for making some sweets.
This happens precisely to exploit the characteristic and pungent flavor of this culinary product . In fact, commonly, wandering the streets of Tokyo or other important Japanese cities, it is possible to come across ice cream sellers . Well, take a look at the flavors… it will not be rare to find wasabi ice cream, recognizable by its unmistakable bright green color .
What if you want to stay more on the traditional and alternative uses of wasabi paste? Then you cannot fail to try the combination with chocolate , even better if dark. Do not you trust? If you could observe wasabi-based products in Japanese markets , you would have confirmation that this unlikely pairing is actually well known in Japan.
Wasabia japonica pasta can also be combined with dishes that are not necessarily based on fish. Just think of the buckwheat noodles known as Soba.
These noodles can be eaten cold or hot in broth and are very often combined with wasabi. The latter can be added both as a cream to enhance the flavor of the pasta, and as a powder as a garnish.
Fun fact: wasabi and soy sauce
Very often, especially in restaurants that promote Japanese cuisine, wasabi is served in a small bowl next to another saucer in which to pour soy sauce. This pairing is not accidental.
In fact, in Japanese restaurants, it is advisable to dissolve a little wasabi in the soy sauce in order to mitigate its spiciness. At the same time, this combination is able to guarantee a better flavor to the wasabi paste . The combination of the two ingredients is optimal and Japanese restaurateurs believe it can help enhance the flavor of sashimi . Well, this is a typical example of revisiting a local tradition.
In fact, in Japan, mixing the two ingredients is strictly forbidden.
As the saying goes, the truth is in the middle and in this food dichotomy, this proverb finds a very right location. Just think that in soy sauce, a minimal amount of wasabi is already dissolved!
The Wasabia japonica plant assumes, when adult, a typically shrubby habit and a height of up to 50-70 cm. It is a perennial plant for which there is no precise season for harvesting the root.
In fact, wasabi can be grown all year round by monitoring the growth status of the seedling. This will be able to produce seeds only 5-6 years after germination.
The wasabi plants find their best territorial localization in humid environments, to be precise along the streams.
The cold, continuous and flowing waters identify the best conditions for the development of the plant. It can grow on soil or in running water, but also in swampy soil . However, in the latter case, it contains lesser quantities of active ingredients and is therefore considered of lower quality. For this reason, if you decide to cultivate the plant, it would be advisable to place it in conditions of continuous irrigation, for example in hydroponic crops .
The stem appears very thick and characterized by large internal channels that allow it to develop even in semi-aquatic environments.
This structure, known as the aeriferous parenchyma , allows the plant to receive the right oxygenation despite being partially submerged. As the plant grows and emerges from the water , the stem takes on a woody consistency, losing both the aeriferous parenchyma and the lower leaves.
The leaves appear large, characterized by a very intense green color and a typical heart shape.
Rhizome or root
In the first years of development, the plant has a simple root system. Over time, the roots will evolve into the rhizome , which is a reserve structure that will accumulate the isothiocyanates characteristic of wasabi inside .
The rhizome appears only between the third and fifth year.
This occurs simultaneously with the reaching of maturity of the plant.
Wasabi: historical notes
When it comes to wasabi, it is inevitable to think of Japan.
In fact, the history of the Land of the Rising Sun is strictly connected to the exploitation of this plant by its population . A book of ancient Japanese culture and tradition, known as Engishiki, dating back to the 10th century, even points out that wasabi root was used as a substitute for money .
In the logic of barter, varying amounts of this root were in fact used to pay taxes to the Japanese central government .
Coming to the 14th century, many recipes, especially by Buddhist monks, see wasabi as an ingredient in various culinary preparations.
Given the economic wealth connected with this root, until 1774, the cultivation of the plant was allowed only to a ‘chosen’ few.
This bond was lifted only in this year although a control of the shogun was maintained over those who decided to cultivate it.
Despite this, in some areas of Japan, wasabi cultivation took off strongly. Two of these areas only the regions of Amagi and Izu , which are currently considered among the main producers of this edible ‘gold’ .