OpenRiver
Student Research and Creative Projects 2012-2013 Grants & Sponsored Projects
9-1-2012
Ethyl Acetate Extraction of Humulus Lupulus Compounds with Characterization by Gas Chromatography-Mass Spectrometry
Benjamin Martin Winona State University
Francis Mann Winona State University
Follow this and additional works at: https://openriver.winona.edu/studentgrants2013
Recommended Citation Martin, Benjamin and Mann, Francis, "Ethyl Acetate Extraction of Humulus Lupulus Compounds with Characterization by Gas Chromatography-Mass Spectrometry" (2012). Student Research and Creative Projects 2012-2013. 27. https://openriver.winona.edu/studentgrants2013/27
This Grant is brought to you for free and open access by the Grants & Sponsored Projects at OpenRiver. It has been accepted for inclusion in Student Research and Creative Projects 2012-2013 by an authorized administrator of OpenRiver. For more information, please contact [email protected]. Appendix C
RESEARCH / CREATIVE PROJECT ABSTRACT / EXECUTIVE SUMMARY FINAL REPORT FORM
Title of Project Ethyl Acetate Extraction of Humulus Lupulus Compounds with Characterization by Gas Chromatography-Mas Spectrometry
------
Student Name Benjamin Martin
Faculty Sponsor Francis Mann
Department Chemistry
------
Abstract Hops are an essential ingredient in flavoring and preserving beer. Hops contain two main types of compounds: α-acids and β-acids, which are the essential oils. I studied these volatile compounds such as humulone, an α-acid, and myrcene and humulene, which are β-acid. Humulone, like other α-acids, gives beer a bitter flavor via isomerization. Unlike α-acids, β-acids flavors are based on which chemical compounds are present in the hops. For example, myrcene produces a floral, citrus, and piney flavor, while humulene creates a spicy, and herbal aroma. Additionally I investigated the effect on my compounds of interest during the brewing process, more specifically when and how the hops were added. The relationship between bitter and aroma is crucial for obtaining the desired taste. Ethyl Acetate is used to extract the desired volatile compounds from my hops; this allowed me to use Gas Chromatography- Mass Spectroscopy to visualize and identify the desired compounds.
------
The end product of this project in electronic format has been submitted to the Provost/Vice President for Academic Affairs via the Office of Grants & Sponsored Projects Officer (Maxwell 161, [email protected]).
Student Signature Date
Faculty Sponsor Signature Date
Ethyl Acetate Extraction of Humulus Lupulus Compounds with Characterization by Gas Chromatography-Mass Spectrometry
Benjamin Martin and Francis M. Mann Winona State University, Department of Chemistry
Introduction Results Results Hops are an essential ingredient in flavoring and preserving beer. Hops contain two main types of compounds: α-acids and β-acids, which are the essential oils. I studied these volatile compounds such as humulone, an α- acid, and myrcene and humulene, which are β-acid. Humulone, like other α-acids, gives beer a bitter flavor via isomerization. Unlike α-acids, β-acids flavors are based on which chemical compounds are present in the hops. For example, myrcene produces a floral, citrus, and piney flavor, while humulene creates a spicy, and herbal aroma. Additionally I investigated the effect on my compounds of interest during the brewing process, more specifically when and how the hops were added. The relationship between Conclusion bitter and aroma is crucial for obtaining the desired taste. Ethyl acetate is When looking at the hops that were followed it appears that they are comprised mainly of α- used to extract the desired volatile compounds from my hops; this allowed acids, which help create a more bitter beer. This means that four of the five compounds should me to use Gas Chromatography-Mass Spectroscopy to visualize and be present in greater concentrations as the additions get later into the brewing process. Simcoe appears to follow this trend, however, this doesn’t seem to be the case for the other four hops. identify the desired compounds. This led me to believe that the α-acids are being volatilized in the brewing process instead of being isomerized. Furthermore, stigmasta-4,22-diene-3-beta-ol is a β-acid and has a large molecular weight, which means it should retain its concentration throughout the additions. Once 1 1 β-caryophyllene Caryophyllene oxide α-humulene1 again, Simcoe appears to follow this trend while the others do not. The proposed reason for this is that stigmasta-4,22-diene-3-beta-ol is breaking down rather than evaporating. Thus, these trends seem to show that each variety of hops react to the brewing process differently. This can β-myrcene1 Stigmasta-4,22-diene-3-beta-ol be caused by the hop plant composition, size of leaves, or concentration of α- and β-acids in the leaves and flowers.
Methods Future Applications • The initial step in my project was to gather information on all eighteen of my hop plants by extracting the compounds, in ethyl acetate, from dry hops. Knowing the characterization of hops compounds, and the flavoring those compounds • This allowed me to find five hops that contained β-caryophyllene, α-humulene, caryophyllene oxide, produce, will allow brewers to choose the variety of hops that best suits the formation stigmasta-4,22-diene-3-beta-ol, and β-myrcene. of their desired product. Furthermore, knowing the compounds that reside in each • I then made micro-brews using simcoe, northern brewer, centennial, golding, and willamette, which were the variety will allow researchers, such as myself, to further investigate each compound five hops I chose. for potential medicinal purposes. One such compound is xanthohumol, which is • In this brewing process I added 1 liter of water, 120 grams of malt syrup, and 1.5 grams of hops. the hops were isolated from certain varieties of hops and thought to have cancer chemopreventive added at three different time points during the 90 minute brewing process (30 minutes in, 60 minutes in , and 3 80 minutes in). The 30 minutes time point represents the bittering of hops, which help the α-acids isomerize. characteristics. The 60 minute time point represents the flavoring step, which prevents total isomerization of α-acids and complete elimination of β-acids. The final time point at 80 minutes represents the finishing step, which retains the β-acids.2 • After the brewing process, the samples were filtered into a bottle where equal parts of ethyl acetate were added to extract the compounds. Acknowledgements • The samples were allowed to settle and then the organic layer was separated into a 500-mL round bottom flask • WSU for an Undergraduate Research Travel Grant and dried down to 4.56 mL on the rotovap. • WSU for an Undergraduate Research Grant • These sample were diluted to 1/100 solution and analyzed using an Agilent 6890 GC paired with a quadrupole • WSU Chemistry Department for the use of the GC-MS MS detector. • Dr. Francis Mann for her guidance and leadership on my project
Results References 1.Sigma Aldrich 2.Miller, Dave. The complete Handbook of Home Brewing 1988, 201. 3.Magalhães PJ; et al. “Fundamentals and Health Benefits of Xanthohumol, A Natural Product Derived From Hops and Beer”. NCBI PubMed 2009, 4, 591-610.