Hopping into your own craft beer: the chemistry of picking good hops
Barley and hops https://learn.kegerator.com/evaluating-hops-smash-brewing/
Fermented brews have been a part of human culture since before recorded history, but it wasn’t until the end of the dark ages in Germany that hops were added and true beer was brewed. Before that the ales brewed wouldn’t last long before microbes spoiled them. but thanks to the naturally antimicrobial alpha-acid compounds of the wild European hops(Hyptis suaveolens) beer could last for months(G. A. Pankey).
Now, beers could be transported across the continent. Brewers exchanged and experimented with different flavors, aromas, and medicinal properties bestowed by the hop.
All this attention has pressured selecting the best hops for brewing for so many generations that they’ve effectively been domesticated into the modern species you are familiar with, Humulus lupulus.
Humulus lupulus is now farmed all over the world for its bitter A-acids, aromatic essential oils, and its medicinal and antimicrobial resins, all found in the lupulin glands of the hop’s flower.
(left)Hop flower https://en.wikipedia.org/wiki/File:Hopfendolde-mit-hopfengarten.jpg
(right) Cross section of hop flower http://indiehops.com/images/hoptour10_266x.jpg
Many have tried to determine a unit for “hoppyness” by investigating these glands through crushing. this is a good first step in discovering some profiles of the hop, but there are many different a-acids responsible for different flavor profiles(Urban), and many different aromatic compounds in the essential oils that can produce different “spice” flavors in the final product than the fresh hop(Graham). Unfortunately, the volatile nature of these compounds causes some of these aromas to evaporate before they can be incorporated into the final product. some aromatic compounds begin to evaporate as soon as the hop is broken and can be gone in seconds(Kralj). This means the only way to determine a hop’s full profile without a lengthy brewing process is steeping a hop tea.
Humulone – the major alpha acid component of hop resins.
The best way to brew a beer that accentuates your hops is to experiment. The home brewers association’s beginners guide gives step by step instructions for brewing small batches. This is the best test because there may be some clues you can get from fresh hops but the only way to really know how your hops (or oil extracts) will perform under pressure is to put them to the test.
Kralj, D., Zupanec, J., Vasilj, D., Kralj, S. and Pšeničnik, J. (1991), VARIABILITY OF ESSENTIAL OILS OF HOPS, HUMULUS LUPULUS L.. Journal of the Institute of Brewing, 97: 197–206. doi:10.1002/j.2050-0416.1991.tb01066.x
Urban, J., Dahlberg, C. J., Carroll, B. J. and Kaminsky, W. (2013), Absolute Configuration of Beer′s Bitter Compounds . Angew. Chem. Int. Ed., 52: 1553–1555. doi:10.1002/anie.201208450
Department of Food Science, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand, and Australian Centre for Research on Separation Science, Department of Applied Chemistry, RMIT University, G.P.O. Box 2476V, Melbourne, Victoria 3001, Australia
- A. Pankey, L. D. Sabath; Clinical Relevance of Bacteriostatic versus Bactericidal Mechanisms of Action in the Treatment of Gram-Positive Bacterial Infections. Clin Infect Dis 2004; 38 (6): 864-870. doi: 10.1086/381972
“MoreBeer Brewing Techniques – The Essential Oil of Hops: Aroma and Flavor in Hops and Beer.” MoreBeer Brewing Techniques – The Essential Oil of Hops: Aroma and Flavor in Hops and Beer. N.p., n.d. Web. 10 Feb. 2017.