"Once young people eat it and they realise it's good, they will eat it more and more," Hideki Tokoro, the head of Japan's main whaling firm, said at the event at Tokyo's main wholesale fish market.

"People are excited about the fin whale... It's just delicious," he told AFP in his trademark whale-themed hat and jacket.

Since 2019, Japan has caught whales in its own waters after abandoning under international pressure hunting for "scientific purposes" in the Antarctic Ocean and the North Pacific.

The catch list was limited to sei, minke, and Bryde's whales, but this year fin whales -- the planet's second-largest animal -- were added and on August 1 the first killed.

Tokoro's firm Kyodo Senpaku hopes the taste of fin whale will revive demand and help it recoup the costs of its new 9,300-tonne "mothership".

Almost every part of the whale was on display, including slabs of heart, slices of tail and chunks of blubber.