Karebushi

Rather than being used to make arabushi, the dried pieces of katsuo can undergo further processing to create the ultimate in katsuobushi for dashi making purposes, which is called karebushi. After being dried further in the sun and reshaped, the blocks are inoculated with a beneficial mould that promotes fermentation. This in turn breaks down the proteins in the fish into amino acids, which increase the levels of the umami taste in the fish. This drying and moulding process is repeated up to three times to create an extremely hard block. At this stage, the weight of the block is roughly ⅙ of the original weight as it has lost its water content. High quality shavings, bursting with flavour and aroma, can be taken from karebushi. These refined, high quality karebushi, though more expensive than non-moulded arabushi, are prized for making dashi and have a stronger umami taste than arabushi. They are particularly favoured when making formal kaiseki cuisine. They are also more popular in the Kanto area of Japan, around Tokyo.