Domestic Hop PelletsAll one ounce pellet hops are packaged in air-tight bags to insure you the freshest product available. Hop plants are climbing vines (more accurately, bines: vines without tendrils). The plant part used in brewing beer is the hop flower, a delicate, pale green, papery cone full of perishable resins. They give a beer bitterness when used early in the brewing process, and aroma when added at the end.