USES: As a seasoning, much like lime juice, in salsas, marinades and soups.
Other names: Naranja (without the agria) in Yucatan, Seville orange, bitter orange.
FINDING: Occasionally in Latin American, Mediterranean and some well-stocked groceries.
CHOOSING: A typically bumpy-skinned sour orange that is unblemished, not withered and feels heavy is the best-tasting, juiciest one.
STORING: In the refrigerator, loosely wrapped, for up to a month.