Ume is usually translated as “plum” in English, though in fact the fruit is more closely related to an Apricot.
The Ume are cured in salt for two weeks, then cured for another 4 weeks with red shiso leaves around them, which gives them a red colour.
The pickled Ume ends up with a sour, salty taste. They are used as a condiment, even at breakfast.
They can be bought in cans and jars.
Many people still make them at home, usually in mid-summer when the fruits are unripe. Unripe Ume are first soaked in water to leach bitterness out of them. The fruit is then removed from the water, wiped dry, and sprayed with rice vinegar, after which they are mixed and coated with salt. A weight is put on top of them, then the container is covered and let sit for a few weeks.
Shiso leaves are then washed, drained, salted, and squeezed of the liquid that comes out of them. The leaves are then mixed in with the Ume, then the weight and cover are replaced on the fruit for a few more weeks. At the end of the process, they are often let dry outside in the sun for 2 to 3 days.
The brine that is produced is referred to as “Umezu.” It can be used for other culinary purposes.
Plums arrived in Japan in the 700s from China.