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Comet Hops

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Comet was developed in 1961 and released in 1974 by the USDA. It was selected for its high alpha acid content and it was highly adapted to growing in the Yakima Valley. Commercial production ceased in the 1980s in favor of newer super-alpha hops. Comet has recently found new interest for use as a dual-purpose hop. This is due to its grapefruit, tangerine, grassy, and herbal characteristics which make a unique “wild American” aroma.

Country of Origin:United States
Hop Growers Code:COM

Where To Buy Comet Hops

Comet Hops

Comet is an interesting bittering hop which has made a comeback. Comet has a blend of both wild grassy aromas and zesty grapefruit character. Generally used for bittering, the flavor and aroma of this hop beg to be experimented with in late additions.

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Comet Flavor And Aroma

Comet is a dual-purpose hop that is often described to have the following aroma characteristics:


mandarin, tangerine


wild grass, lemongrass



Comet Hop Oil Breakdown

Hop oils can vary year to year and farm to farm but based on our research, here are the typical values we have seen reported. This information comes from various hop farms, The Hop Aroma Compendium, and For The Love Of Hops.

Alpha Acid % (AA)
Alpha acids are what is isomerized when boiling to create bitterness in beer.
8% – 10.5%
Beta Acid %
Beta acids are what give hops their more aroma and flavor compounds.
4% – 5%
Alpha-Beta Ratio
This ratio of alpha acids to beta acids determines how quickly bitterness fades during aging. Lower ratios are common for aromatic varieties.
1:1 – 4:1
Co-Humulone as a % of Alpha
Higher numbers are said to impart a harsher bitterness.
34% – 37%
Total Oils (mL/100g)
With more total oils, typically comes a more complex hop profile but these are highly volatile compounds.
1mL – 3.3mL
green, resinous
50% – 60%
woody, piney
0.5% – 2%
8% – 13%
0.1% – 1%
Other Oils: Includes beta-ionine, beta-pinene, limonene, linalool, geranoil & selinene21.2% – 39.9%
Hop Storage Index (HSI)
The HSI indicates the percent of alpha and beta acids lost after 6 months of storage at room temperature (68°F or 20°C).
Retains 67% of its alpha acid after 6 months of storage at 20ºC (68ºF).
Hop Storage Index (HSI) RatingFair

Comet Hop Substitutions

Replacing one hop for another is seldom straightforward but sometimes you don’t have the right hop or the right quantity of hops for the beer you want to make. For those situations, we have made a comprehensive list of hops to substitute on brew day.

These substitutions aren’t perfect as hop chemistry is pretty complex.

We wanted to make this list of substitutions with varietals that are easy to find when possible. For Comet, we recommend substituting with the following hops:

Beer Styles

For the most part, any hop could have a place in just about any beer style. Based on popular beers, historical usage, and our own preferences, we would recommend using Comet hops for Lager, IPL, IPA, Pale Ale, and Stout. That being said, experiment and see what works best for you.


Hieronymus, Stan. For The Love of Hops. Brewers Publications, 2012
The Hop Aroma Compendium. 2012