Metabolomics of hops and beer Katy Benson M.S. UC Davis 2014 - - PowerPoint PPT Presentation

Metabolomics of hops and beer

Katy Benson M.S. UC Davis 2014 Brewery Management Development Trainee, MillerCoors

Overview

• Definition of metabolite/metabolomics and the process
• Inspiration for my research
• Hop and commercial beer metabolomics
• A novel compound in hops and beer
• Brewing trials and analysis
• Conclusions

What is metabolomics?

Standard Metabolite: a product of metabolism, small-molecules. e.g. ethanol, amino acids, sugars, organic acids

• ome/-omics: totality, global view.

e.g. genome/genomics, proteome/proteomics Metabolite X at Y concentration (quantitative)

NMR: absorption and emission

• f electromagnetic resonance

Inspiration for my research

What metabolites make hops significant? What metabolites make beers different? Can this be detected in a sensory study?

First steps…

Metabolite Cascade Magnum 4-Aminobutyrate 9.48 14.37 Acetate 2.05 4.05 Acetone 0.18 0.18 Alanine 9.43 8.37 Arginine 12.05 14.39 Asparagine 114.31 183.77 Aspartate 2.15 3.08 Choline 6.27 5.68 Creatine phosphate 0.34 0.07 Cytidine 0.14 0.22 Ethanolamine 1.43 0.88 Formate 1.50 1.27 Fructose 31.29 23.85 Fumarate 1.08 2.46 Glucose 56.56 34.37 Glutamine 4.44 3.51 Guanosine 0.38 0.50 Histidine 2.46 3.27 Isoleucine 0.64 0.67 Malate 28.94 56.64 Malonate 0.49 0.91 Methanol 1.49 1.17 Methylsuccinate 2.73 1.21 N-Nitrosodimethylamine 0.41 0.32 O-Phosphocholine 0.56 0.81 Phenylalanine 0.52 0.66 Proline 2.70 3.36 Succinate 2.63 5.72 Sucrose 43.63 21.21 Threonine 1.85 2.34 Trigonelline 1.32 2.12 Tryptophan 0.60 0.89 Tyrosine 3.02 2.03 Uridine 0.59 0.54 Valine 1.04 1.84 myo-Inositol 6.33 3.46 sn-Glycero-3-phosphocholine 1.26 1.26

Non-polar (not water soluble) fraction Polar (water soluble) fraction (Bamforth 2006)

Pale Ale vs IPA Cascade vs Magnum

Pale Ale vs IPA Cascade vs Magnum

Late vs Dry Hopping?

First steps…

A new compound in hops & beer

Trigonelline

• Plant alkaloid that has been detected in sources

such as coffee and fenugreek (Kidrič and Košir 2006, Zhou, Chan et al. 2012).

• Along with similarly-structured nicotinic acid,

implicated as anti-diabetic agents, in that they improve the glucose tolerance in obese diabetics (Yoshinari and Igarashi 2010).

• Implicated in various contexts as anti-bacterial,

anti-viral, sedative, anti-migraine, and anti-tumor (Zhou, Chan et al. 2012).

• Precursor to coffee aroma compound.

~50% carryover from hops to beer

Brewing Trials

5-gallon brewing set-up at UC Davis.

5 beers

Late-hopped Magnum Late-hopped Cascade Dry-hopped Magnum Dry-hopped Cascade Control (hopless)

5 process samples

• 1. Start of kettle boil
• 2. After whirlpool
• 3. After yeast pitch
• 4. After fermentation (14 days)
• 5. After bottle conditioning (28 days)

4 replicates

Results of Brewing Trials: Metabolites

Results of Brewing Trials: PCA Analysis

Clustering according to global metabolite profile

Principle Component Analysis: statistical analysis to identify important variance

Results of Brewing Trials: Heat Maps

• 1. Start of kettle boil
• 2. After whirlpool
• 3. After yeast pitch
• 4. After fermentation (14 days)
• 5. After bottle conditioning (28 days)

= more = less

Conclusions/Further Directions

At the detection limit of NMR, the metabolite profile of a final beer is primarily determined during fermentation, with the exception

• f a few compounds including…

Trigonelline is a novel compound in hops and in beer, and shown to carry forward throughout the entirety of the process. Environment and small variations in process have significant impact on the metabolic profile of final beers. The role of hops as contributors of amino acids (FAN) is novel and to be further elucidated.

Acknowledgements

• Dr. Charlie Bamforth

Candy Wallin

• Dr. Carolyn Slupsky
• Dr. Ann Spevachek

Rachel Gescheidle Tom Nielsen & Gil Sanchez (Sierra Nevada) Toby Eppard Alex Combe

Thank you!!