Editor’s note: The theme of Gohan Lab is to help people make simple, tasty “gohan” (meals).

* * *

How you cut and cook lotus root determines its texture. When deep-fried or simmered, it comes out somewhat crumbly; when grated and heated it becomes springy.

But its true value emerges when prepared with a crunchy texture with a distinctive pierced look, which you can learn to do in this week's recipe for the staple dish in our second installment in our series on root vegetables.

“Su-renkon,” literally “vinegar lotus root,” is a convenient precooked dish that can work as a side on its own or with “chirashi” scattered-style sushi or salad.

Due to its almost transparent white appearance, su-renkon is one of Japan's auspicious New Year dishes, representing wishes for “good visibility.” 

Its unique texture and sour taste that stimulates the appetite will keep you from putting your chopsticks down.

Despite its somewhat plain appearance, su-renkon is packed with nutritional value.

Cooking it takes three steps: cutting the lotus root, boiling, and immersing it in a seasoned liquid. If your slices turn out too thick, cook them longer to adjust their firmness. Use whichever type of vinegar you prefer.

For a refreshing flavor, try a mild cereal vinegar. To go richer, immerse the lotus root in rice vinegar with a moderate fermented smell.

Highly nutritious and goes well with Western food 

Japan's top producer of lotus root is Ibaraki Prefecture, which produces nearly half of the crop's annual yield.

The root vegetable, which is “rich in nutrition such as vitamin C and dietary fiber, also suits Italian cuisine and other Western dishes due to its lack of a strong taste,” said a spokesperson for JA (Japan Agricultural Cooperatives) Suigo Tsukuba co-op, located in Tsuchiura city. 

Lotus roots grow in fields knee-deep in water. Farmers used to have to dig them out of the mud with hoe-like tools that could scar the vegetables, but now they are harvested using hoses that splash away the surrounding dirt with water pressure.

When you're shopping for them, make sure that the cut end is not discolored. Since they are liable to dry out, wrap them with plastic wrap and place in the vegetable drawer of the fridge when storing.

Another way of keeping lotus root fresh is to immerse it in a bucket of water, imitating the environment it grew in. Renew the water daily and use the lotus root up within a few days.

BASIC COOKING METHOD

(Supervised by Akiko Watanabe in the cooking aspect and Midori Kasai in the cookery science aspect)

* Ingredients and cooking utensils (Serves two)

1 section of lotus root (160 grams), 1/2 cup vinegar, 2 and 1/2 Tbsp sugar, 1/2 tsp salt, peeler, kitchen knife, cutting board, bowl, sieve, pot, long kitchen-use chopsticks

1. Prepare enough vinegar water in bowl to cover lotus root. It should contain 1 percent vinegar to water, such as 1 tsp vinegar (not listed above) to 500 ml water. Remove skin with peeler. If lotus root is wide in diameter, cut in half lengthwise. Thinly slice into 2-mm-thick pieces (PHOTO A). Immerse in vinegar water right away after slicing. When cutting is done, drain water in sieve.

2. Bring water to a boil in pot, add lotus root and boil for 2 to 3 minutes. Drain well and cool. 

3. To make seasoning liquid, pour 1/4 cup hot water, sugar and salt in bowl or heat-resistant glass container and dissolve (PHOTO B). Add vinegar.

4. When liquid has cooled, add lotus root (PHOTO C). The taste settles down after about an hour. To use the dish for a salad, mix with slices of onion or cucumber and tossed with mayonnaise. Putting smoked salmon or uncured ham between two slices of lotus root makes a great snack to go with drinks.

* * *

Akiko Watanabe is a cooking expert specializing in Japanese cuisine.

Midori Kasai is a professor at Ochanomizu University and chairwoman of the Japan Society of Cookery Science.

ARRANGED VERSION

<“Kinpira” lotus root>

Thinly slice 160 grams of lotus root as in the vinegar-flavored version. Soften 1/3 chili pod by immersing in hot water. Remove seeds and slice in rounds. Pour 1 Tbsp oil in frying pan and place over medium heat to stir-fry lotus root. When oil has coated all pieces, add 2 Tbsp water and sautee while mixing until evenly transparent. Add chili, 1 Tbsp soy sauce, 1 tsp sugar and reduce over medium heat while mixing until liquid is gone.

COOKERY SCIENCE

You can reduce discoloration in the sliced lotus root by immersing it in water right away. If you add vinegar to the water, the lotus root will turn out whiter. In the mildly acidic vinegar water, the action of the oxidizing enzyme that brings on the discoloration is hindered. In addition, the flavonoid pigment that is colorless in a neutral state turns white in an acidic environment.

* * *

From The Asahi Shimbun’s Gohan Lab column