The leaves are stripped from the stems and taken to a room where ...
... huge fans fling them into the air. Light leaves fly farther than the heavier stalks, and the sorting of the soft leaves is thus done automatically.



The leaves are spread out in the yard and exposed to sunlight for a couple of days.
The leaves are temporarily put into straw bag (Zukin).



The leaves are then brought to their 'bedroom' and piled up to a height of about one meter.

Well water (not tap water) is sprinkled over the pile, and it is all stirred. This needs to be repeated every 5~7 days.


As the fermentation proceeds ammonia gas starts to fill the room. But as you would imagine Mr. Nii still manages to keep his eyes open! The amount of water is carefully controlled according to the condition of the leaves. The fermentation will stop if the amount is either too much or too little.


This work is called 'Kirikaeshi'. They stir this huge pile of leaves up and down and from the center to the outside, so that oxygen can reach all the leaves, allowing fermentation to proceed evenly.

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