The fruit of the almond tree has long been valuable in the cooking of Europe and the Middle East. The almond is also important for its oil, which comes primarily from the bitter almond (not cultivated in the United States). Almond extract or essence, used in desserts and baking, is processed and distilled from the residual crushed kernels of bitter almonds. Because the strongly flavored kernels contain toxic prussic acid, they must be heated before being eaten in any form. See nuts.
Peaches, apricots, plums, and cherries are all cousins of the almond, so they have a natural affinity for one another. Noyau is a French extract made from the kernels of these fruits, which can be processed into a syrup or liqueur. Macarons are flavored with almond extract, but for amaretti di Saronno an extract of apricot kernels is used. See macarons.