The process involves starting banana trees out at a frigid -60 degrees centigrade, then replanting the trees with their still-ripening bananas to a more temperate climate of around 27 degrees centigrade -- an environment banana trees typically grow in the entire time.

The extreme temperature variation encourages the plants to grow rapidly, and leaves the fruit with a peel that has a texture like "lettuce," D&T spokesman Tetsuya Tanaka told the New York Post.

Staff working at Japanese news site SoraNews24 tried the fruit. While acknowledging the peels were truly edible, the tester thought, however, that there wan't much flavor to the skin.

The mongee banana is currently available in only one regional Japanese outlet, with each banana going for around 6 U.S. dollars.

Banana is the most popular fruit in Japan. According to Japan's financial magazine Toyo Keizai, in 2016, households of more than two people in Japan buy an average of 18 kg of bananas a year, well ahead of the No. 2 fruit, mandarin orange, at 13 kg a year.