2.
Frothy collection of bubbles formed at the top of beer
Also called beer head or froth
Formed by interactions between proteins and gas
What is beer foam?
3.
How is it made?
Okayama University discovered
the three major proteins that
contribute to beer foam:
Lipid Transfer Protein 1 (LTP1)
Z4
Z7
Hydrophobic due to alpha-helical
folding
Blasco, 2011
U of U 2016
• Proteins surround gas bubble and
ride up to the surface
• Creates bubble lattice on top of beerBech, 1995
5.
LTP1 is the main contributing
factor for beer foam production
Globular form in raw barley
Becomes denatured during
“mashing”
Denatured form is active
Z-proteins are foam stabilizing
Major factors in foam retention
How do these proteins affect
beer foam?
6.
Temperature (Foam +/-)
1. Mashing
2. Serving
Due to CO2 solubility
Detergents/lipids (Foam -)
ABV (alcohol by volume) (Foam -)
Etching in the glass (Foam +/-)
Nucleation sites
What can affect beer foam?
7.
Why do we want foam?
Releases odor compounds (aromatic esters) to the
surface
contribute to smell and taste of beer
Acts as a Trigeminal sensation
Due to Cranial Nerve IV (much like spicy
foods and mint)
Foam means there is still carbonation in the
beer!
When flat, beer will produce little to no foam
because of two reasons:
1. No gas means no foam
2. There is a limited supply of proteins
It Makes for a great Mustache!
Theawesomer.com
8. Foam measuring machine
Mechanical sensor that follows the beer down the glass as
the foam decays
This measures:
How fast the foam deteriorates
How much foam
How do you quantify beer
foam?
9. Onshi and Proudlove, Japan: Looking to see what was in beer foam
Used nitrogen to create foam
The foam was then separated into two fractions through column
chromatography
1. High molecular weights
2. Low molecular weights
How did we find out about
these proteins?
Kai, 2013
10.
The high molecular weight fraction:
contained mostly carbohydrates
10 percent protein (these proteins were the
two Z-proteins (Z4 and Z7))
The small molecular weight
fraction:
Mostly proteins
later found to be LTP1
What were their findings?
LTP1 molecular structure
Bech, 1995
Z- protein. EMBL 2015
11. Van Nierop et al, South Africa
Two South African breweries
(Brewery A and B)
Asked to brew the same exact beers
using the same exact raw materials
They were given identical sampling
time intervals
Wanted to know:
Any differences in the way they
make beer
Would this affect beer foam
production?
How Denatured LTP1 Was
Found To Create Beer Foam
Samuel Adams, 2014
12.
Brewery B’s beer contained more foam and higher levels of
LTP1 (through ELISA) than Brewery A’s beer
Brewery A was at an attitude of ~200 meters above sea level
Brewery B was at an altitude of ~1800 meters above sea level
Why does altitude matter?
Brewery B is at a higher altitude which means they are
brewing at lower atmospheric pressure compared to
Brewery A
Brewery A wort boiling ~ 102 Degree Celsius
Brewery B wort Boiling ~ 96 Degrees Celsius
Results of South African
Brewing Experiment
13.
Results of South African brewing
experiment (continued…)
Table 1 LTP1 levels measured via ELISA over the brewing process at breweries
A and B (Van Nierop et al, 2004)
14.
Brewery B had higher LTP1 levels due to lower
temperatures and less denaturation
Brewery A had lower LTP1 levels due to proteins
being denatured to a greater extent to a non-
functional conformation
LTP1 was more effective at binding free fatty acids
when it is not fully denatured
Results of South African brewing
experiment (continued…)
15.
Results of South African brewing
experiment (continued…)
Brewery B Brewery A
Van Nierop et al, 2004
16. YES!
Growing barley in drier climates helps produce more LTP1 in
the barley thus creating more beer foam when brewing
Some scientists have taken pure mixtures of denatured LTP1
and tried to introduce it after fermentation. This created beer
foam that was very unstable and did not last long
German scientists have spliced the gene encoding for LTP1
production into yeast cells. These cells then create LTP1
during fermentation increasing the concentration and causing
for more beer foam
Have we tried to brew
with more LTP1?
17. Foam Mug
Creates bubbles that induce foaming
Etched glasses (Guinness created a special
glass)
Creates more nucleation sites = More foam
We have the devices to
create more foam!
Guinness, 2010
18. 1. LTP1 is the major protein involved in foam
production
2. Z4 and Z7 maintain beer foam stability
3. Without these proteins beer would not be as
enjoyable as it is with an aromatic full bodied beer
head
Conclusions
19. Agric, James. "A Heady Discovery for Beer Fans: The First Gene for Beer Foam
Could Improve Froth." Journal of Agriculture and Food Chemistry 60.43 (2012):
10796-0807. Phys.org. Web. 19 Dec. 2015.
Allain, Rhett. "Modeling the Head of a Beer." Wired.com. Conde Nast Digital, 25 Jan.
2009. Web.
"Beer Head Retention-| Brewer's Friend." Brewers Friend RSS. 19 Dec. 2009. Web.
"Carbonation - What You Need to Know To Help You Serve Draft Beer." Draft Beer
Made Easy. 2009. Web.
Christensen, Emma. "Good Foam, Bad Foam: What's the Deal with Beer Foam? -
Beer Sessions." Thekitchen.com. 2012. Web.
Colby, Chris A. "Getting Good Beer Foam: Techniques." Getting Good Beer Foam:
Techniques. Brew Magazine, 5 Dec. 2005. Web.
Evans, D.e., and J. Hejgaard. "The Impact of Malt Derived Proteins on Beer Foam
Quality. Part I. The Effect of Germination and Kilning on the Level of Protein
Z4, Protein Z7 and LTP1." Journal of the Institute of Brewing 105.3 (1999): 159-
70. Web.
Work Cited
20. Gerritson, Vivienne B. "One Beer Please." Protein Spotlight The Full. SIB Swiss Institute of
Bioinformatics, 01 May 2004. Web.
Halford, Bethany. "Four Tips for Getting the Best Beer Foam." Newscripts. Chemical and
Engineering News, 03 May 2013. Web.
Karl, Siebert J. "Recent Discoveries in Beer Foam." Journal of the American Society of
Brewing Chemists ASBC 72.2 (2014): 79-87. Web.
"Kilning | Beverage Production." Encyclopedia Britannica Online. Encyclopedia
Britannica. Web.
Lees, Michael A., Peter A. Rodgers, Duncan B. Campbell, Michael A. Pecar, and David C.
Shudarmana. "Intelligent Systems for the Brewery Based on Real-Time
Measurement of Biological Parameters." Australian Barley Technical
Symposium 53.1 (1999): 313-16. The Regional Institute.
"Plant Lipid Transfer Proteins." Wikipedia. Wikimedia Foundation, 02 Dec. 2015. Web.
Rudin, A. D. "Measurement Of The Foam Stability Of Beers." Journal of the Institute of
Brewing 63.6 (1957): 506-09.
Veneri, Gianluca, Gianni Zoccatelli, Silvia Mosconi, Chiara Dalla Pellegrina, Roberto
Chignola, and Corrado Rizzi. "A Rapid Method for the Recovery, Quantification
and Electrophoretic Analysis of Proteins from Beer." Journal of the Institute of
Brewing 112.1 (2006): 25-27.
Work Cited Cont…
21. Bader, Heinz Peter. Foam in Beer. 2014. Corbis, Seattle,
Washington.
Bech, M. L. Barley LTP1 Molecule. 1995. European Brewery
Congress, Brussels.
Blasco, Lucia. Foam Structure. 2011. Microbid International,
Barcelona, Spain.
Santilli, Laura. Gene for Beer Foam. 2005. Fotolia, New York. Kai.
Yeast and O2. February 2, 2013. Braukaiser, Germany.
Urie, Brendon. Guinness Mustache. 2011. Tumbler, Dublin,
Ireland.
The Mo-Gaurd. Theawesomer.com, California.
Vesicle. University of Utah. 2016. LearnGenetics.com
Picture Citations
Talk Notes:
Condense slides to bare bones
Slow down talk and get to a conversational level
Record talk, listen to talk and visualize slides
Avoid basically
Add lacing to slide and lacing beer picture
How do we know this? Give credit to source who originally found proteins
Talk about hydrophobic region (water fearing) in more clarity …ect…
Comes from Barley!
LTP1, Z4, Z7 come from this plant and are introduced into the beer during “Mashing”
Don’t have time to explain the entire flow chart but address the main topics “mashing and barley”
Add gif of beer foam rising in beer (pouring, head, over run)
Bring points in 1 by 1
If worried about time – this is the slide to go
Break up into 2 slides
Can explain there are other methods that work alongside this technology but do not have time to go over it
Fix graphic. Make clearer. Make smalller or retake picture
Explain axis
Look of pronunciation of “denaturation”
The higher the temp the more open the hydrophobic regions of LTP1 which wont bind lipids and so these lipids will work against LTP1 by depleting beer foam
Summary of how they stumbled across how LTP1 was more active in its denatured state
Redo this slide- change . Modify
Be more specific on who used LTP1
Put citations at the bottom or (rjdgwa,1933)
Guinness pic- Rib in the glass
If needed to drop slide – this is the one