Pickled green buds from the Mediterranean shrub. They are smaller than raisins and bottled in brine and used as flavoring.
The preserved blossom bud from a Mediterranean bush of the south has a circular appearance, typically less than the size of a pea, with a dusky complexion, and an acute, remarkable flavor. Notably, the designated “English caper” is not sourced from this vegetation, but rather from a brined Nasturtium seedpod.
This passage is describing a food ingredient called capers, which come from the flower buds of a shrub that grows in southern Europe. The buds are picked when they are still fresh and then allowed to dry for a day before being put into a brine for pickling. After that, they are canned in vinegar. Capers are often used to add flavor to sauces, including tartar sauce which is typically served with fish, as well as a sauce traditionally served with boiled mutton.