Views: 24 Author: Site Editor Publish Time: 2022-11-18 Origin: Site
It is after the drying stage that processing for whole hops and pellet hops diverge. Hops bound for the pellet are hammer milled, which creates a powder. This gummy powder is then forced through a extrusion die, turning them into hard shiny pellets and something that looks akin to lifestock feed. The hops ruptured lupulin sacs supply both the binder and protective coating, thus their shiny appearance.
The quality of the pellets is critically affected by the temperature and speed throughout this process. Mill them too fast and discoloring, scorching, and oxidation are likely to occur. So it is extremely important to mill at low speeds and keep the whole process cool by liquid nitrogen or some other means.
After milling the pellets are allowed to cool and harden. These cured hops are then precisely weighed, packaged in vacuum sealed barrier bags, boxed, and set in cold storage until sold.
Pellets sink and dissolve, creating a clear surface area advantage and, in turn, utilization advantage. This utilization advantage is further heightened by lupulin glands that have been ruptured by the milling process; making the isomerization of alpha acids easier. Both, the surface area and alpha acid availability translate to a 10 to 15 percent increase in utilization over whole hops.
Though, technically this increase is not high enough for a brewer to change the hop amount in a recipe when going between the two forms, if you find that there is a harsh quality to a beer after switching to pellet hops, it may be worth trying the same recipe with a slightly downsized dose.
The outer shell of lupulin resin helps protect the pellets from oxidation giving them a longer storage life, with less chance of damage to quality. Pellet hops are also easier to measure out, work with, and take up less storage space than whole hops. These factors together, actually produce another advantage to the home brewer; the availability of more hop varieties.
Most of the disadvantages of pellets stem from their advantages. They sink and dissolve, meaning they create “sludge” on the bottom of your brew kettle or fermenter. If in the fermenter it can impede siphoning. Also, if a dry hop addition is added too early it’s possible that dead yeast cells may cover the hop powder, limiting wort contact.
The extra processing due to milling can negatively affect the aromatic quality. Whole lupulin glands allow a slow release of essential oils giving time for some oxidation of humulene and other hydrocarbons. The ruptured glands of pellets means a loss of a major portion of these compounds long before their oxidative states have a chance to form.