Loomi: the dried lime most kitchens walk past
Limes boiled in salt water and left in the sun until they are hollow, hard, and somewhere between tan and black. That is loomi, also sold as black lime or noomi basra. If you have not used one they look like something that should have been thrown out, and they rattle.
The taste is sour, but not the sour of a fresh lime. Drying and fermenting strip the sharp top note and leave something deeper and slightly musty, closer to tamarind than citrus, with bitterness underneath. Fresh lime hits the front of your mouth and disappears. Loomi sits under a dish and stays.
Whole and ground are effectively two ingredients. Whole, pierced a few times and dropped into a stew, it gives a background sourness that builds over a long cook and perfumes the liquid without taking over — take it out before serving, because nobody wants to bite one. Ground, it is far stronger and more direct, which is why it turns up in rubs and in most Gulf baharat. Too much ground loomi turns a dish muddy and bitter. Start with one whole lime for a stew serving four to six, or a quarter teaspoon ground.
It belongs in long-cooked things: lamb and chicken stews, rice dishes, anything with tomato that needs cutting through. It works particularly well against fat, which is why it sits so naturally with lamb. It also does something useful in a dish that already has fresh acid — lemon on top, loomi underneath. The two do not compete, because they occupy different parts of the palate.
They should feel light for their size and rattle, which tells you they dried properly; heavy ones can be damp inside. Colour runs from pale tan to almost black, and darker generally means stronger and more bitter. They keep more or less indefinitely somewhere dry, and any Middle Eastern grocer has them for very little.
