Ah, the many joys of canned food. It's readily available, keeps well and can be nutritious and even eaten without heating.

Many of you may have likely turned to canned food at times during the stay-at-home period brought about by the government's requests to help combat the novel coronavirus.

Beginning this week, we're introducing a series of four recipes that will help you make dinner using canned food.

First up is canned mackerel, which has become tremendously popular in recent years.

“The best part of canned food is that you get to eat the bones, skin and all," says Kuniaki Arima, the chef who oversaw the cooking aspect of the recipe. "The flavor of the dish will be enhanced by using the broth as well.”

We've chosen to pair our mackerel with grilled eggplant, which is now in season and absorbs all the liquid in the can.

Ragout is a sauce that incorporates sliced stewed meat and seafood. The ingredients are simmered until the flavors blend thoroughly. The salt already in the can forms the basis of the flavor and miso makes up for what is lacking.

The mackerel is suitable as a main dish and even tastes good cold. If you plan to eat it with chopsticks, cut the eggplant into bite-size pieces beforehand and mix with the sauce.

Fat-busting action behind canned mackerel surge

Production of canned mackerel approached 45,000 tons in 2019, exceeding canned tuna made from tuna and skipjack. The volume increased by nearly 60 percent in 10 years, Japan Canners Association data shows.

The production process involves cutting up the mackerel and packing it in the can, adding the seasoning and sealing the can, and heating under pressure and sterilizing, according to Nippon Suisan Kaisha.

Canned mackerel's popularity is due to its nutritional benefits, the added bonus that you can even eat the bones and seasoning liquid, and the fact that it's handy for cooking, the company said.

“Behind the surge in its popularity is that its rich content of EPA (eicosapentaenoic acid) that plays a part in the metabolism of fat under the skin as well as visceral fat was a good match for the trend toward being health-conscious," Nippon Suisan Kaisha said.

BASIC COOKING METHOD

(Supervised by Kuniaki Arima in the cooking aspect and Midori Kasai in the cookery science aspect)

* Ingredients (Serves two)

1 can of mackerel (plain “mizuni” type) (190 grams), 1 eggplant (large and roundish “beinasu” type), 1 tomato, 1/2 onion, 1/2 clove garlic, 50 to 80 ml olive oil, 1/2 tsp miso, 2 Tbsp water, two pinches finely chopped Italian parsley

About 545 kcal and 1.0 grams salt per portion

1. Crush garlic and chop coarsely. Finely chop onion. Cut tomato into large bite-size pieces. Peel eggplant and cut into four thick slices. To make them look like steaks, cut off bit of round edge.

2. Pour 50 ml olive oil in frying pan, lay in eggplant and place on low to medium heat.

3. When eggplant slices become tender (PHOTO A), push to one side and add garlic in empty space. When aroma rises, add onion and cook. When onion starts to become transparent, add tomato and liquid of canned mackerel (PHOTO B). Lower heat and simmer to allow eggplant to absorb liquid.

4. When simmering liquid has boiled down to about a half, turn eggplant slices and add miso and water. Add mackerel pieces and simmer for about 5 minutes while loosening them by crushing lightly. When liquid boils down (PHOTO C), add parsley.

***

Kuniaki Arima is the owner-chef of Passo a Passo, an Italian restaurant in Tokyo’s Fukagawa.

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

ARRANGED VERSION

Salad with mackerel and bread

Make a filling salad by letting a baguette absorb the liquid in the can and mixing it with summer vegetables.

Pour liquid of a can of mackerel in bowl, add 2 Tbsp each of water and wine vinegar, 1 and 1/2 Tbsp olive oil, bit of salt and mix. Cut 50 grams of baguette into bite-size pieces, add to bowl and let them absorb the seasoned liquid for 10 to 15 minutes.

Add 1 Tbsp each of boiled corn and green soybeans (“edamame”) and mackerel pieces and mix while crushing fish. Divide salad onto two to three lettuce leaves used as containers and eat while wrapping by hand. Tomato and green peas may be added if preferred.

COOKERY SCIENCE

After the fish is canned, it is sterilized under pressure and heat of over 100 degrees. Through this process, the collagen, which is a constituent of its hard bones, loosens, breaks up and dissolves. This allows the bones to be eaten as well. The process where insoluble collagen turns soluble is called gelatinization and the higher the temperature, the more likely it is to occur.