Makrut or Kaffir Lime

Ma krut is the Thai name for the tree also known as kaffir lime (“kaffir” is Arabic for “unbeliever” and has derogatory connotations). This Southeast Asian member of the citrus family, Citrus hystrix, has distinctively aromatic leaves and fruit rinds that are an important ingredient in Thai and Laotian cooking, especially soups, stews, and fish dishes. The rind has an unremarkable mix of citrus, pine, and fresh notes, but the tough leaves are richly endowed with citronellal, which gives them an intense, fresh, lingering lemon-green character distinct from that of sweeter citral-flavored lemon-grass (with which it’s often cooked). Citronellal is named for citronella, its original and main source, which is a sister species to lemongrass (Cymbopogon winterianus).