Hops are one of the main ingredients in home-brewed beer. If you are a home brew enthusiast, growing your own hops and harvesting the fresh, pungent cones is an important part of the process. Home-growing your hops allows you access to a variety that appeals to you and adds the depth of flavor you need to please your taste buds.
Historically, hops have been used to balance the sweet with the bitter flavoring in malted beverages, while enhancing the brews stability. The earliest documented mention of hops as a brewing aid is from the 9th century. The part of the hops used are the cones, which are essentially the flowers of the plant and contain sticky greenish yellow powder. The entire cone, as well as the grains, are part of the flavoring for beer. They also enhance the antibacterial balance, helping preserve home-brewed beers.
The scientific designation, Lupulus, stems from the Roman observation that hops grew wild like wolves among sheep. By the 13th century, hops were being used predominantly for flavoring beer and had displaced the traditional mixture of herbs previously in use.
These vigorous plants thrive in full sun and well-drained soil during spring and summer. In winter, they die back to the rhizome, which will re-sprout the following spring.
Hops produce lovely, rampant bines, which make decorative greenery over trellises and arbors. Over time, the length of the bines will increase and plants can grow 25 to 30 feet long each season.
There are several varieties from which to select, each of which has slightly different flavor profiles , but they are generally divided into two types: aroma hops and bitter hops. Aroma varieties tend to impart fruity, citrus, spicy, earthy, and floral notes, while the bitter hops have a higher alpha acid percentage and may impart smokey, herb, or resin flavors to beers.
Hops are ready for harvest at the end of the growing season. Most varieties need at least 120 frost-free days before harvest, but the actual duration will depend upon the zone and variety grown. Hops need to be harvested before the first killing frost, between August and mid-September.
Crushing a ripe cone will yield an impressive aroma and release the yellowish powder from the glands. Ripe hops will feel dry and papery when they are ready for harvest.
To harvest them, you have to undo your carefully trellised or stringed bines. Hand-cutting cones away from the bines is traditional. These newly harvested cones need to be dried completely before storage. The usual method is on wire frames or screens in a dry location. Move cones every day to expose any moist areas to the air.
You may also opt to dry the cones in a food dehydrator or oven that is set at 140 degrees or less. As with screen dried cones, continually moving them around will ensure complete drying.
Storing Dried Hop Cones
It is best to use hops in the season in which they were harvested in order to preserve optimal flavor and aroma characteristics of your chosen variety. However, once cones are completely dry, you can store them in a cool location where oxygen is reduced. (Oxygen breaks down the a-acids and can result in a "cheese-like" aroma characteristic of old hops.)
However, vacuum-sealing and even zip-sealing plastic bags can be used to store hops in a freezer. The aroma hops store longer with less acid loss than the bitter types. Cold storage temperatures must maintain 30°F or colder. Cold seems to slow the oxidation process, as does a dark storage area, since light also degrades the cones.
In commercial production, the hops are bound into bales wrapped in burlap or ground and extruded as pellets. Home growers will likely use a chest freezer or cold cellar to keep their crop fresh.
How Long Do Hops Last?
The duration of storage will vary depending on the style of storage and the conditions. Variety, alpha acid content, temperature, light and oxygen exposure will all contribute to how the cones preserve while in storage.
Pelletized hops last longer than cones because they have less surface area to expose to light and oxygen. In perfect conditions, even cones can be stored for up to two years, but degradation will still occur.
The Hops Storage Index (HSI) is available at many brew sites and in homebrew books. It calculates the amount of alpha acid lost over a period of time. In good storage conditions, hops will last three times longer than their HSI indicates. As with any herbaceous substance, time is your enemy, as the best flavors and attributes will belong to fresher hops. Careful storage and knowledge of the HSI for your variety are key to successful storage and retention of the alpha acids and flavor.
How Much Hops Do I Use in My Brew?
Calculating the right amount of hops for your brew will depend upon the flavor you wish to achieve and the variety of hops you have at your disposal. Often this is a matter of trial and error, adjusting the amount with every batch you make until you have the perfect balance of hop and sweet malt flavor.
There are standard charts that can help guide you as you navigate the home brewing world. One such from the Beersmith Home Brewing Blog indicates different beer varieties and the amounts of hops needed. You can always adjust from there to personalize your brew.