John Maye (1), Robert Smith (1), Jeremy Leker (1); (1) Hopsteiner, New York, NY, U.S.A.


The major contributors to beer foam are hop acids and malt proteins. Most brewers are familiar with the foam-enhancing properties of isoalpha-acids, tetrahydro-isoalpha-acids and hexahydro-isoalpha-acids. However, given the recent popularity in dry-hopping, some craft brewers are experiencing poor beer foam. The reduction in beer foam from dry-hopping could be due to the change in hop acid composition that occurs with dry-hopping or due to the incorporation of hop oils or fatty acids. To better understand what causes this reduction, beer foam was tested via the Nibem foam stability tester before and after dry-hopping. Non–dry-hopped beers were also spiked with a variety of hop acids, hop oil, and fatty acids to simulate a dry-hopped beer in order to better understand what causes the reduction in beer foam and what craft brewers can do to remedy it.

John Paul Maye is the technical director at Hopsteiner. He has over 20 years of experience in the hop industry. He received his Ph.D. degree in organic chemistry at Purdue University in 1994 and started his work as a hop chemist in 1993 at Pfizer’s Brewing Ingredients Division located in Milwaukee, WI. He has published several papers on hops and received several patents on hops and their applications inside and outside the brewing industry.