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HOP PRODUCT INFORMATION

The Pacific NorthwestOregon State University began a selective breeding program for hops about 60

years ago. In 1972 they were able to release the first variety Cascade. Since that

time they have been releasing other successful varieties such as Willamette, Nugget,

Mt. Hood and Crystal. These varieties were developed to be disease resistant and to

produce higher alpha acid yields, and in fact the program at Oregon State has been

referred to as the High Alpha Acid Breeding Program.

The USDA has released a complete list of all varieties grown in the US, see

the USDA Named Hop Variety Descriptions.

The Oregon Hop Commission has all kinds of information on varieties grown in

Oregon. Oregon is the second largest producer of Hops in the U.S. and are grown

mainly in Marion, Polk and Clackamas counties.

Yakima county Washington is another growing area with high-alpha varieties, and

has been a source of Hop growing for many years, some of the largest hop growing

farms in the Northwest are in the state of Washington.

Freshops uses mostly Northwest growers in obtaining the best quality Hops

available. Some Hop varieties are obtained from England, Germany, New Zealand,

and the Czech Republic.

Hops(Humulus lupulus)A rough twining vine with separate male and

female plants. The female bears flowers in the form of cones.

Hops are unisexual, only the female hop produces the flowers

that are used in brewing. As the female flower matures, they

form cone like structures. The mature hop cones are 1 to 3 inches

long, yellowish green, and papery to the touch. These cones are

harvested in August and September and dried. Vigorous

varieties will produce as much as 2 lbs. of dried flowers per

plant. The dried ripe cones are used in brewing for bittering,

flavor and aroma, preservation and head retention.

LupulinHop varieties get their properties or active principles from tiny

yellowish glands tucked at the base of the cones' petals within thebracts or scales. The gland is covered by a waxy skin within

which lies all of the hops unique bittering (alpha acids) and

aromatic (oil) compounds. These glands are referred to as

Lupulin.

The Quality of Hops depends largely on the amount of lupulin

they contain. When derived from the fresh hop flowers it is more

abundant and of better quality.

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Alpha AcidsThe bitterness level of a particular hop variety is measured in

percent alpha acid by weight. the higher the percentage, the

more bitter the hop in direct proportion. As hops age, the alpha

acid oxidizes and the bittering potential diminishes. This is why

hops should be kept frozen or at least refrigerated. As long as thecurrent years harvest is used, the amount of alpha acid lost is

acceptable. Freshops has each variety analyzed for alpha acid

and this percentage is indicated on each package. When using

hops for bittering, a boil of approximately one hour is

recommended to incorporate the bitterness into the wort.

Alpha acids are now the accepted method in the brewing

industry for assessing the quality of the hops. Almost everywhere

in the world the alpha acid content of each variety and each hop

harvest and each individual consignment of hops is measured.

Alpha acids play a decisive role in determining prices and

quantities bought in the hop trade today.

Using alpha acid percentages

Once you determine how bitter (alpha acid units) you like a

particular style of beer, simple algebra is used to balance

changing varieties and alpha acid percentages.

Cascade- alpha 5.5% x 2 ounces = 11 alpha acid units Chinook-

alpha 10.7% x Q ounces = 11 alpha acid units Q= 11/10.7 = 1.028

ounce

HOMEBREW BITTERING UNITS (HBU's)

A measure of the total amount of bitterness in a given volume of

beer. Homebrew Bittering Units can easily be calculated by

multiplying the percent of alpha acid in the hops by the number

of ounces.

For example, if 2 ounces of Northern Brewer hops (9% alpha

acid) and 3 ounces of Cascade hops (5 % alpha acid) were used

in a 10-gallon batch, the total amount of bittering units would be33: (2x9)+(3x5)=18+15. Bittering units per gallon would be 3.3 in

a 10-gallon batch or 6.6 in a 5 gallon batch, so it is important to

note volumes whenever expressing bittering units.

INTERNATIONAL BITTERING UNITS (IBUs)

A measure of the bitterness of a beer in parts per million(ppm),

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or milligrams per liter(mg/l) of alpha acids. You can estimate the

IBUs in your beer by using the following formula:

IBU= (ounces of hops x %alpha acid of hop x %

utilization) gallons of wort x 1.34

Percent utilization varies because of wort gravity, boiling time,

wort volume and other factors. Homebrewers get about 25%

utilization for a full one-hour boil, about 15% for a 30-minute

boil and 5% for a 15 minute boil. As an example, 1 ounce of 6%

alpha acid hops in 5 gallons of wort boiled for one hour would

produce a beer with 22 IBUs:

IBU = 1 x 6 x 25 =22

IBUs

5 x 1.34

METRIC BITTERING UNITS (MBUs)

MBUs are equal to the number of grams of hops multiplied by

the percent alpha acid.