The focus this time is on the king of fish, maguro. Witness the highlight of an auction site at Japan's largest market, Toyosu Market, as one-third of wholesalers are maguro specialists. Our reporter visits Katsuura Fishing Port for a famous haul. Last but not least, don't miss this program's lineup of irresistible maguro dishes.

Lemons first came to Japan some 150 years ago, and have since been blended with Japanese citrus fruits to create brand-new types. We journey to a tiny island in the Seto Inland Sea where some 25% of Japanese lemons are grown and discover its unique, lemon-friendly climate and topography. We also see the surprising ways lemon farmers use lemons in Japanese cuisine from tempura to hot pot. Last but not least, we pucker up for some delicious lemon-based sweets.

Onions are eaten throughout the world, but in Japan, they're cooked with original techniques and used in a variety of Japanese dishes. This time, we bite into some of those dishes, including one available for just a short time in spring and another that features onion leaves. How have onions influenced Japanese cuisine? Join us to find out!

This episode features natto, a fermented soybean product known for its powerful smell and sticky texture. Both economical and nutritious, natto is a staple Japanese breakfast food. Mito, north of Tokyo, is the natto capital of Japan. See how traditional, organic natto is made, and have a look at a variety of unique dishes that feature natto.

Our focus today is hijiki, a variety of seaweed that has been consumed in Japan for over 1,000 years. Much like tea leaves, this nutritious, low-calorie food is often dried, and soaked in water before use. Hijiki grow quickly at the start of spring on rocky coastlines, and are only available for harvest for a few days. Dive in to find out more about what ancient Japanese considered to be a gift from the sea

Matcha is known worldwide as a popular ingredient in sweets. But originally, matcha is green tea leaves pulverized into micron-sized powder and mixed into hot water to make tea. We visit Uji, Kyoto Prefecture, a place where matcha is traditionally cultivated and produced, and learn how matcha is used in the tea ceremony, which is considered to encapsulate the spirit of Japanese culture and hospitality. Finally, we see how its unique bitterness is used to create a variety of novel dishes.

The Karei is a type of flatfish beloved in Japan. Karei is great as sashimi, of course, but also simmered, grilled, deep-fried, and more. In short, it can be enjoyed in a variety of ways through the year. This time, we travel to Oita Prefecture in Kyushu, the southernmost of Japan's main islands, to discover a highly-valued type called Shiroshita-karei. There, we talk to fishermen and chefs to discover what is behind the great flavor of this fish.

Today we focus on Aji, or horse mackerel, one of Japan's most popular types of fish due to it being both delicious and economical. Seki-aji is a rare fish caught in the tides of the narrow straits of Kyushu known for its outstanding umami. Experienced fishermen must read the tide and rely on their intuition. Our reporter goes out to fish with one such expert, and also visits a high-class sushi restaurant to learn about Aji sushi preparation methods that vary according to fish size.

Today, we focus on the king of fruit, mango. Though often thought of as a tropical fruit, they are also grown in Japan. Large, delicious, gorgeous Japanese mangos are traded at incredibly high prices, and are often given as gifts. Our reporter visits a mango grower in Kyushu to learn more about the secrets behind the production of this high-end fruit. Also enjoy unique seasonings made from mango.

This time, we dip into Japanese vinegar. There are many kinds of vinegar worldwide, like balsamic, wine, and malt. But in Japan, most vinegar is made from rice. Rice vinegar is a subtly sour ingredient that matches all kinds of Japanese cuisine and is vital in the making of sushi. We visit a Kyoto Prefecture vinegar maker that does everything in-house, even growing their own rice. We also sample a variety of dishes that incorporate vinegar, like sushi and other traditional Japanese cuisine.

Japanese eggplants vary in size, shape, flavor and more depending on the climate in which they're grown. In summer, peak season, many varieties line the shops. We visit Niigata Prefecture, Japan's largest eggplant consumer, to discover its unique eggplant culture. That culture includes special eggplant cooking methods and even eggplants salt-pickled in clay! Plus, we learn about the deep connections between eggplants and ancient Japanese customs.

This episode focuses on Kanpyo -- a white, stringy, and noodle-like food unique to Japan that is actually peeled and dried parts of a vegetable. Kanpyo-maki is a popular snack easily found in convenience stores. It is also used in place of string to keep foods in form. 90% of Kanpyo production takes place in Tochigi Prefecture, where one can witness exciting production methods, and taste various Kanpyo recipes from Japanese cuisine, sweets to French cuisine.

Over the years, Japanese cheese has evolved to win international prizes. It has a rich aftertaste and umami characteristic of all Japanese cuisine. Visit leading natural cheese factories in Hokkaido Prefecture, Japan's largest dairy producer, to discover the secrets behind enhancing quality and a process that involves burying cheese in the ground. Also, meet a young cheesemaker who strives to make his small town famous for blue cheese.

Japanese rice is known for its strong stickiness and sweetness. In Japan, where cooked rice is eaten without seasonings, focus is placed on the deliciousness of rice itself. In spring, planting season, farmers pray to the deity of the harvest for a good crop. In fall, people around Japan celebrate the delicious new rice. Some even have festivals! In Japan, rice is more than just food: it's connected to religious beliefs and culture. This time, rice, which continues to be loved by the Japanese.

Today we focus on the most cultivated fruit in Japan, the mikan -- a palm-sized citrus fruit that is so soft and easy-to-eat, you could eat an entire batch. In the autumn and winter seasons, a plentiful amount of mikan can be found in nearly every Japanese home. Learn more by visiting an orchard in Wakayama Prefecture, where mikan trees are seen lined up on steep hills.

Hokkigai, or surf clam, has a special place in the hearts of the Japanese thanks to its thick meat, unique umami and nutritional value. It's great not only as sashimi, but grilled, deep-fried and more. Over 80% of the Hokkigai caught in Japan comes from Hokkaido Prefecture. We visit Tomakomai, a port city in Hokkaido, and discover the various ways Hokkigai is prepared and eaten there, from sushi to curry! We also find out how fishermen use safe, cutting-edge fishing methods to protect the species.

This time, we dive deep into soba, Japan's iconic buckwheat, which is used to make soba noodles. Soba long supported the lives of mountain dwellers who could not grow rice or wheat. It also has deep ties to Japanese culture, and is eaten to pray for long lives and more. Ever wondered why you slurp soba noodles in Japan? We discover the very special reason. We also visit a traditional production area and see the various ways soba is prepared there.