The bitter orange tree is one of the most useful for perfumery—every part yields an interesting raw material. The flowers provide orange blossom absolute and neroli oil, the leaves and tender buds give petitgrain, while the fruit peel contains the wonderfully rich and complex bitter orange oil.
Orange blossom and neroli are extracted from the flowers of the bitter orange tree (Citrus bigaradia), with the different methods of extraction determining the type and olfactory characteristics of the resulting oils. Orange blossom oil is extracted with volatile solvents, while neroli is steam-distilled. The former is warm, jasmine-like, with a sweet grape and indolic twist, while neroli is greener and spicier. The fruit of the bitter orange tree produces bitter orange oil (the distinctive note in Frédéric Malle Cologne Bigarade), and its leaves give the sparkling verdancy of petitgrain oil.
The more commonly encountered orange oil (sometimes called sweet orange oil) is actually the product of a different tree, the sweet orange tree (Citrus sinesis), and while its blossoms can also be steam-distilled, the result is an inferior, less fragrant grade of neroli. The flowers of other citrus varieties also yield either absolute or essential oil. One of my favorites is grapefruit flower oil, which was used to give a scintillating floral top note to Tom Ford for Men.
Neroli and orange blossom oils are among the most important ingredients in perfumery, decorating the top accords of chypre compositions, lending a fresh touch to floral bouquets and forming the bodies of classical colognes. A whole family of floral oriental fragrances was developed around the pairing of lush orange blossom and the warm accord of vanilla, heliotrope, musk and oriental balsams. This idea was first explored by Coty L’Origan and subsequently by the marvelous Guerlain L’Heure Bleue.
Winter is the season for bitter oranges; in addition to their uses in perfumery, they make for an aromatic flavoring in the kitchen. The peel can be used to make marmalade or can be made into a fragrant paste. Simply remove the colored zest, grate or mince it with an equal amount of sugar and store it in the fridge. Use a little bit to flavor anything from shortbread and rice pudding to fruit salad and lamb stew. Bitter orange juice can be substituted in any recipe calling for lemon. It is intensely tart and complex, and it will give a bright, floral fragrance that is reminiscent of green mandarins, fresh leaves and white petals.
Photo of bitter oranges from Flickr by basecadet, some rights reserved.