Coffee Curiosity

INFO 526 - Summer 2024 - Final Project

Cristina Lafuente

Why do we experience coffee the way we do?

  • TidyTuesday dataset had taste test. What is bitterness and acidity?
  • Organic acids (OA) and Chlorogenic Acids (CGA) give coffee flavor
  • There are over 50 different acids (OA and CGA) studied by Yeager et al
  • Each roast and blend has its own concentration
  • CGAs contribute to the acidic notes until heated then become bitter
  • OAs contribute to acidic notes in coffees.

What variables are coming in from the study?

 [1] "Source"         "Type"           "Roast"          "Extraction"    
 [5] "Stat"           "Other"          "Units"          "Citric"        
 [9] "Formic"         "Malic"          "Pyruvic"        "Quinic"        
[13] "Succinic"       "Acetic"         "Oxalic"         "Fumaric"       
[17] "Tartaric"       "Lactic"         "Glycolic"       "Nitric"        
[21] "Mesaconic"      "Maleic"         "Isocitric"      "Citraconic"    
[25] "Propionic"      "2-Furoic"       "Pyroglutamic"   "Phosphoric"    
[29] "Levulinic Acid" "Methylsuccinic" "Nicotinic"      "Ascorbic"      
[33] "Hydroxybenzoic" "Total"          "Notes"         
 [1] "Source"                    "Type"                     
 [3] "Roast"                     "Extraction"               
 [5] "Stats"                     "Other"                    
 [7] "Units"                     "total CQA"                
 [9] "Total FQA"                 "Total diCQA"              
[11] "3-CQA"                     "4-CQA"                    
[13] "5-CQA"                     "3-FQA"                    
[15] "5-pCoQA"                   "5-FQA"                    
[17] "Ferulic Acid"              "4-FQA"                    
[19] "3,5-diCQA"                 "3,4-diCQA"                
[21] "4,5-DiCQA"                 "3-pCo,5-CQA"              
[23] "3-C,4-FQA"                 "3-C,5-FQA"                
[25] "4,5-FQA"                   "3-C,4-FQA and 3-pCo,4-CQA"
[27] "3-C,5-DQA"                 "3-C,4-DQA"                
[29] "3-D,5-FQA"                 "Nicotinic Acid"           
[31] "3-CGA"                     "Total CGA"                
[33] "Notes"

Questions

  • Do people experience and quantify coffee’s acidity and bitterness in a way that is consistent with objective data? And do their coffee preferences affect their perception?

  • Does political affiliation play any part in coffee preference?

Lightest Coffees

Darkest Coffees

Who is right?

Coffee Preference by Political Party

               political_affiliation Democrat Independent No affiliation Republican
prefer_overall                                                                     
Coffee A                                 0.22        0.23           0.23       0.15
Coffee B                                 0.19        0.20           0.21       0.27
Coffee C                                 0.19        0.21           0.21       0.24
Coffee D                                 0.41        0.35           0.35       0.34

Conclusions

  • It is possible that there is some correlation between those who prefer light roast and the more accurate perception of coffee’s bitterness but only sightly.

  • Political affiliation does not appear to play any real role in coffee preference though it is interesting to note that Republicans were the only party to prefer Coffee B (second to D)

  • Possible source for future study - remove coffee D and retest political affiliation and preference.

Source

Yeager, S. E., Batali, M. E., Guinard, J. X., & Ristenpart, W. D. (2021). Acids in coffee: A review of sensory measurements and meta-analysis of chemical composition. Critical Reviews in Food Science and Nutrition, 63(8), 1010–1036. https://doi.org/10.1080/10408398.2021.1957767