Your sushi experience is in danger due to climate change; but this time it’s not the fish

Among all the cuisines in the world, Japanese is considered to be the healthiest because of the abundant use of fresh produce, rice and seafood. 

Through the decades, the popularisation of sushi has brought with it the culture and traditions of Japan to the world. Japanese food started gaining traction in India in the late 2000s by way of fine-dining restaurants that flew in most of the ingredients from their source. The expensive, but unique flavours attracted a lot of crowd and soon Japanese food was a trend among the fashionable young generation. To this day, among all the dishes served, Sushi remains the top contender.

A well-made sushi is seasoned in layers and textures - right from the seaweed used to wrap the rice in, the wine or vinegar used to season the fish, to the wasabi that it’s served with, every element of sushi is just as important as the other. The absence of even one element will take away from the sushi eating experience, and that is bad news for everyone who has sharpened their chopstick skills. 

The green, spicy condiment wasabi does more than just add heat to the sushi. It also counters the smell of raw fish with its hot vapours, enhances appetite, and prevents food poisoning. In Japan, chefs at higher-end restaurants grate fresh wasabi at the counter for customers to experience the burst of flavour that lingers on the tongue for just a moment. In its most authentic form, wasabi can be deemed as the most important element of your sushi plate. 

However, it happens to be one of the most difficult commercial crops to grow in the world. To this day, wasabi cultivation is a skill that is handed down to generations because the knowledge to grow and maintain the farms takes immense patience and attention to detail. A number of factors affect the flavour of wasabi, including water quality, temperature, stones, insolation, and the presence of organic matter among other things. Good wasabi is produced when there is a constant flow of clean spring water, rocky soil, gravel and a shaded area. Even then, it is vulnerable to pests and diseases. 

The ideal temperature for the crop to thrive is between 11 and 19 degrees Celsius. It is fairly resistant to cold, growing naturally as far north as Sakhalin, Russia, but will freeze if the temperature falls to 5 degrees below zero. To keep them from freezing, therefore, the plants are covered with nets in the winter. In the summer they need to be shaded because they are susceptible to higher temperatures and can mould or rot in no time if exposed to heat.

According to the Tokyo Foundation for Policy Research, the existence of these wasabi farms is being threatened by external factors like climate change, which upset the delicate balance needed by these plants. However, it is also being threatened by a lack of interest on the part of younger generations to work as their parents and grandparents did.

The Japan Food, Agriculture, and Rural Areas Basic Act, which was enacted in 1999, focuses on farms of four hectares or more, which rules out wasabi farms across Japan as they are too small to receive subsidies. Even the largest of them, in both Utogi and Yamanashi prefecture, has a total acreage of no more than 0.6 hectares.

Wasabi fields are located on steep mountains that have been dug and stepped by first generation farmers. These steps help hold the water, which must be kept clean. Along with the scarcity of clean spring water, the ability of soil to hold this water has also added to the reasons for decline in wasabi cultivation. According to the Ministry of Agriculture, Forestry and Fisheries, Japan, over the last decade, the volume of wasabi produced in the Shizuoka prefecture alone has declined by close to 55 percent. 

Hiroyuki Mochizuki, president of Tamaruya, a 147-year-old company in Shizuoka that processes wasabi to sell in tubes, told the New York Times that in order to protect the Japanese food culture, it’s important to protect wasabi. 

Decline in quantity of production due to factors impacting the growth, the cost of procuring wasabi has risen drastically over the last decade. A kilogram of fresh wasabi roots can cost north of $250. In order to keep the demand supply gap to a minimum, companies that process wasabi have started replacing it with horseradish by dying it green. 

Horseradish and wasabi are members of the same plant family, which also includes mustard, cabbage, broccoli, and brussels sprouts. Both are bitter and pungent. However, wasabi has a more complex vegetable flavour and punchy heat to it. 

The cultivation of horseradish stands in stark contrast to that of wasabi. It grows quickly and is a low maintenance crop while wasabi takes a minimum of eighteen months to grow, mature and reach the harvest stage, all while demanding an array of specific factors that impact its growth. While horseradish might not be particularly harmful to health, the additives to make it look like wasabi surely are. If your wasabi isn’t being grated in front of you, it is highly unlikely that it is the real deal.

Despite the rising temperatures threatening to kill their crops, wasabi farmers in Japan continue to be proud of the generational skills and knowledge passed on to them. In the recent past, they have also been open to passing on the skills to people outside the family in order to keep the farms alive. Given Japan’s decreasing fertility rate and increasing population over the age of 65, wasabi farming has to rely on the help and interest of anybody who wants an in into the many well-kept secrets of wasabi farming.