Humulus lupulus Raw Material & Plant Part
The botanical name is Humulus lupulus L., family Cannabaceae, known as hops or common hop. The raw material is the dried female cone, botanically a strobile made of overlapping papery bracts. At the base of the bracts sit the lupulin glands, small yellow resin glands that hold most of the aroma and bitterness. The cones are picked when ripe, dried and then milled. Leaves, bines and roots are not included.
Hop products can mean several things. Brewing hops are sold as whole cones, pellets and extracts, and each form has its own use. The Japanese hop, Humulus scandens, or wild hop, is a different species and is not interchangeable with common hop. The name hops flower in trade refers to the cone, even though a hop cone is not a true flower.
Hop cones are known for bitter resin acids, the alpha acids such as humulones and the beta acids such as lupulones, for essential oil, and for prenylated flavonoids, among them xanthohumol. Alpha and beta acids oxidize in air, which changes the aroma, while xanthohumol is a chalcone that can cyclize in heat and acid.
Drying and storage protect the lupulin. Slow, warm drying and humid storage let the resin acids oxidize, giving a cheesy, stale smell, while quick drying and cool storage keep the fresh, green, resinous character.












