|
Effect of Storage Temperature on the Deterioration of Hop Oil |
|
Researched by Michelle U.
|
|
The purpose of this experiment was to determine the effect of storage temperature on the deterioration of hop oil.
I became interested in this idea because I wondered if the temperature at which the hops were stored would have any effect on the amount of hop lupulin.
The information gained from this experiment could help the Yakima economy and the hop industry by showing what temperature you should store the hops to keep the alpha at the level that customers want it, so the hops are useful for their products.
My hypothesis was that the higher storage temperature would increase the deterioration of hop oil stored for 30 days.
I based my hypothesis on a statement by SS Steiner Hop Company employee Jeremy Leker who said, “The cooler temperature the hops are stored at the longer it takes them to deteriorate.”
The constants in this study were:
• Type of hops (Zeus)
• Amount of oil in each sample
• Storage temperature
• Extraction method
• Measurement method
The manipulated variable was the temperature in which the hops were stored.
The responding variable was the amount of hop oil in the hop after being stored in a warehouse for one month.
To measure the responding variable, I used a spectrophotometer.
QUANTITY ITEM DESCRIPTION
1 70 degrees warehouse
1 20 degrees warehouse
3 Bags of Hops
1 Spectrophotometer
1 Pair of safety goggles
1 Meat grinder
1 Shaker
8 227 gram bags of hops
1 Scale
1 Produce bag
600 ml. Toluene
1) Gather all materials.
2) Take 227 grams hops that have been stored in a 10 degree Celsius warehouse for one month and grind them in a meat grinder
3) Run them through the meat grinder again
4) Place the ground hops in a plastic produce bag
5) Measure out five grams (plus or minus 0.02 of a gram) of the ground hops
A. Using the
metal scoop, scoop up small amounts at a time and place them into the
jar that is on the scale until the weight reaches five grams
6) Measure 100 ml of toluene into the jar with the
ground hops7) Place the jar of hops and toluene into a shaker and turn it on
8) Let the shaker run for 30 minutes
9) Using a pipette, measure out 100 ml of the mixed hop and toluene from the jar
10) Transfer into a vial
11) Transfer the vial mixture into the spectrophotometer to measure the wave-lank of the hops and toluene
12) Record the percentage of lupulin
13) Repeat steps 2-12 using hops that have been stored at 21 degree Celsius warehouse
14) Repeat steps 2-13 3 times more, testing once a month
The original purpose of this experiment was to determine the effect of storage temperature on the deterioration of hop oil.
The results of the experiment were that after being in the room temperature warehouse for 30 days the hop alpha (amount of lupulin) deteriorated faster than in the cooler warehouse. The average alpha in the hops after being stored in the 30 degree warehouse was 16.2% alpha. The average deterioration after being stored in the 30 degree warehouse was 10.8%. The average alpha in the hops after being stored in the 70 degree warehouse was 15.1% alpha. The average deterioration after being stored in the 70 degree warehouse was 14.5%.
See the table and graph below.
My original hypothesis was that the higher storage temperature would increase the deterioration of hop oil stored for 30 days.
The results indicate that this hypothesis should be accepted because after being in the room temperature warehouse for 30 days the hop alpha deteriorated an average of 14.5%. After being in the cold warehouse for 30 days the hop alpha deteriorated an average of 14.5%.
After thinking about the results of this experiment, I wonder if different varieties of hops would deteriorate faster or slower than zeus, especially at these same temperatures.
If I were to conduct this project again I would have more samples. I would also test the hops at more storage temperatures. Another thing that I would do is continue the test for a longer time period.
|
Introduction
Hops are an important crop in the Yakima valley. Hops are
valuable for the lupulin oil that they contain. Lupulin is used
as a flavoring in various products. Growers need to protect the
hops to maintain the most lupulin possible. Plants Plants are used for many things, primarily food. They provide oxygen. Some are used for clothes. They can be used for paper, inks, and paints. They are used in fuels, plastics, medicines, shelter, perfumes, and soaps. Plants are sometimes used for dyes, rubber, ropes, and alcohol. They are also used for sports equipment, photographic films, and musical instruments. Plants have many uses in everyday life. Growing of Hops Hops are vine-like plants with heart shaped leaves and pinecone-like flower custers. The scientific name is Humulus lupulus. Hops have rough stems and they have anywhere from three to seven lobes. Hop vines may grow to twenty-five feet tall. They grow in the spring, and they die in the fall. The hops are picked and harvested in the fall. When the plants die the rhizomes, the underground stems, continue living and produce new vines the next spring. The rhizomes are planted in mounds six to eight feet (1.8 to 2.4 meters) apart. Vines are supported with poles or trellises so they don’t spread across the ground. This also allows hops to be planted closer together, so they can fit more plants per acre. Hops will grow in a wide range of soils. The “chief” hop growing countries include Germany and United States. The lead hops producing states are Washington Oregon, and Idaho. Hops have a bitter taste. The female flower gives the hops the bitter taste and its aroma. The bitter taste in the female flower comes from lupulin. Harvesting Hops Hops are harvested in late summer or early fall. The workers first cut the vines by hand. They put the vines into a machine which separates the hops (flower clusters) from the vines. Then the hops are cleaned. After that they are placed in an oven (kiln) that dries them out. The hops are processed into bales and then they are sold to hop distributors or companies. Uses of Hops Hops have many uses in our society. They are used in items such as perfumes and cologne. Another big item that hops are used in is beer. It gives beer its bitter taste. Varieties of Hops There are many kinds of hop varieties. The ones grown in the United States with “super high” alpha are Sun, Zeus, and Tomahawk/Columbus. The ones grown in the United States with “high” alpha is Chinook, Galena, and Nugget. The ones grown in Germany with “super high” alpha are Hallertaur Magnum, Hallertaur Taurus, and Merkur. The ones grown in Germany with “high” alpha are Brewersgold, Hallertaur Nugget, Huller Bitterur, Northern Brewer, and Grion. Classification of Oil Oil is a greasy substance that does not dissolve in water. It does dissolve in a substance called ether. Essential oils come from flowers, fruits, leaves, roots, barks, and seeds. There are many kinds of oil. Most kinds are lighter than water. Most oil is liquid at room temperature. Some are solid at room temperature, such as lard and butterfat. Lupulin Lupulin is a kind of oil. It is a yellow-brown color and it is found in a hop cone. It is one of the oils that are in the hop. Lupulin gives hops their bitter taste. It is very important that the hop doesn’t lose lupulin otherwise the hop is no longer bitter. When that happens, the uses for the hop go down. Toluene Toluene is an aromatic hydrocarbon. Toluene is a colorless liquid while at room temperature. It is also known as methylbenzene. Toluene is less flammable than benzene. It is a good solvent especially for oils. Toluene is used for assorted plastics, cosmetics, beverages, foods, antiseptics, dyes, and perfumes. Summary Hops are grown, harvested, and processed in the Yakima Valley. Their flavor is used for many things. There are many varieties grown. |
|
“Aromatic
Hydrocarbons” Chemistry.
Dolbear, Jeffery E. “Oil.” World Book. 1998 Volume 14 pg 707. “Essential Oils” Microsoft Encarta Encyclopedia Deluxe. 2001 Hershey, David R. Plant Biology Science Project Toronto, Canada. John Wiley and Sons Inc. 1995. Hilton, Jerrold F. History of Hops. October 21, 2005. www.hopsteiner.com “Hop.” Microsoft Encarta Encyclopedia Deluxe. 2001 Leker, Jeremy <jleker@hopsteiner.com> “RE: My Project.” Dec. 5th, 2005. Personal e-mail. Seigler, David S. Hop. November 4, 2005. www.worldbookonline.com/wb/article?id=ar262120&st=hops |
I would like to thank the following people for helping make my project possible:
• My mom for driving me to SS Steiner to conduct my experiment and giving me information on hops
• My dad for supporting me and helping me as much as I need it
• My sister Rachel for being supportive and letting me use the computer when I need to study
• Mr. Newkirk for helping me make my project the best that it could be
• Mrs. Viernes for helping me when I needed it
• Jeremy Leker for being my mentor
• John for giving me information on hops and how they are tested
Top of page