Antimicrobial Effects of Hops
Document Type
Oral Presentation
Campus where you would like to present
SURC Ballroom C/D
Start Date
16-5-2013
End Date
16-5-2013
Abstract
Hops are a main ingredient used in brewing to create and enhance different styles of beer and are the source of hop bitterness acids which include alpha and beta acids. It has been hypothesized that hops reduce microbial growth in beer and contribute to stability of the product. There have been few studies investigating variation of antimicrobial activity in different hop varieties and their effectiveness at reducing growth of different bacterial contaminants. Therefore, we investigated antimicrobial activity of six varieties of hops, with different alpha acid ratings, on growth inhibition of three bacterial species. Discs were soaked in prepared hop extracts and placed on a lawn of bacterial growth in a petri dish. The diameter of growth inhibition was measured after 24 hours. The results indicated significant differences in inhibition among the varieties (ANOVA p < 0.0001) and in among bacterial species (ANOVA p< 0.0001). There was a trend for higher alpha acid hops decreasing microbial growth.
Recommended Citation
Lopez, Wendy and Foss, Eric, "Antimicrobial Effects of Hops " (2013). Symposium Of University Research and Creative Expression (SOURCE). 14.
https://digitalcommons.cwu.edu/source/2013/posters/14
Poster Number
29
Additional Mentoring Department
Biological Sciences
Antimicrobial Effects of Hops
SURC Ballroom C/D
Hops are a main ingredient used in brewing to create and enhance different styles of beer and are the source of hop bitterness acids which include alpha and beta acids. It has been hypothesized that hops reduce microbial growth in beer and contribute to stability of the product. There have been few studies investigating variation of antimicrobial activity in different hop varieties and their effectiveness at reducing growth of different bacterial contaminants. Therefore, we investigated antimicrobial activity of six varieties of hops, with different alpha acid ratings, on growth inhibition of three bacterial species. Discs were soaked in prepared hop extracts and placed on a lawn of bacterial growth in a petri dish. The diameter of growth inhibition was measured after 24 hours. The results indicated significant differences in inhibition among the varieties (ANOVA p < 0.0001) and in among bacterial species (ANOVA p< 0.0001). There was a trend for higher alpha acid hops decreasing microbial growth.
Faculty Mentor(s)
Steve Wagner