Cupping Bowls
A Bee Culture Experiment
This is going to be a long one, so buckle up!
All of the results from this experiment are based on the subjective senses of myself, due to the nature of individual senses this experiment, replicated exactly by a different individual would likely bear different results. This is important to realize from the beginning to avoid misunderstandings later.
I was conversing with Christopher Feran, a coffee industry expert, consultant, green buyer, and lapsed Q-Grader (his words, not mine). The discussion took place on the Discord server belonging to one Lance Hedrick, a coffee influencer who may be well known to some of you. This discussion was regarding cupping and involved several individuals; if you do not know what cupping is a rather oversimplified overview is you put coffee grounds into a bowl, cup or vessel of some kind, saturate it with a pre-determined amount of boiling water, and then you sip and slurp this most unadulterated brew to try to come as close to the unblemished taste of a particular bean beyond simply grinding it with your own teeth, this is used by the industry as a whole as a reliable and repeatable method of assessing a coffees given qualities, or lack thereof.
Side note: Interestingly it is called “cupping” but the vessels are referred to as “cupping bowls” industry wide.
So, Christopher commented that when cupping he finds that a particular cupping bowl, in his experience/opinion, lowered the Q Grade…oh bother, perhaps a glossary would be best but I do loath making people scroll, so:
Q Grade: A Q Grade is where someone who has been trained, tested, and licensed by the Coffee Quality Institute as a “Q Grader” assesses a coffee by cupping (refer to the oversimplified cupping definition above) it, and stares rather intently at the green and roasted beans, and then gives that coffee a score, generally between 60 and 100 (60 being bad and 100 being the unattainable standards your parents put on you), this score is unalterable and unimpeachable if you ignore the fact that taste and smell are subjective and teams of expert Q Graders often devolve into hour long arguments regarding their personal differences in scoring of a coffee; but if you ignore those facts completely Q Grading is totally unassailable, truly the best system, a necessary system, a system that definitely does not contribute to destroying the livelihoods of hard working coffee farmers after their coffee got a score of 85.75 by a white guy in Cincinnati, and not the all venerated 86+ (86 is believed to be the score where specialty coffee becomes TRULY excellent, some roasters will not accept coffees below this score, some roasters go beyond that and state that the coffees must be above even higher scores, like 87.50, and if the coffee scores even .25 points below that it is rejected) and as such roasters back out of their buying contracts and leave the farmer to drown in their own debts…the best system. (Is it the system to blame, or the bad actors within the system? At what point do the bad actors representing the system become the system? A question many people have asked outside the realm of coffee!)
Alright back to our tale: Christopher felt that using one type of bowl (which shall remain nameless to avoid undue trouble with various companies and lawyers) lowered his assessed score by a point (at least) due to the flavours the bowl itself manifested in the cup. Well this got my tiny coffee nerd brain whirling, what if the bowl mattered? This would change the industry, think of the farmers that could be ruined because the Q Grading took place in the wrong type of vessel and lowered the grade by .25 points? Unimaginable (seriously, we (the roasting community) put WAY to much stock in these grades, but that is another blog post, possibly done by someone who knows more than I).
So, I set off on my journey, buying many cupping bowls, and thankfully some fine roasters sent me bowls from their personal stock so I did not have to purchase dozens of a single bowl type (cup type…) By no means do I have ALL the cupping bowls ever made, that would be lunacy, but I have most of the industry favourites before me filling up my tiny roastery, and will use these to conduct our experiments.
THE BOWLS
Barista Hustle Cupping Bowl (Plastic)
Generic Bowl (Plastic)
Libbey Duratuff 24 (Glass)
Libbey Duratuff 35 (Glass)
ACME Cupping Bowl (Ceramic)
Espresso Parts Cupping Bowl (Ceramic)
Rhino Cupping Bowl (Ceramic)
Origami Cupping Bowl (Ceramic)
Loveramics Colour Changing Bowl (180ml) (Ceramic)
Loveramics Colour Changing Bowl (220ml) (Ceramic)
Generic Coffee Mug (Ceramic)
Testing Parameters:
All cuppings were conducted using the same coffee, a coffee I am familiar with and roasted myself, all cupping doses came from the same roast batch of said coffee, each cupping dose was weighed in the same vessel, ground in the same grinder, at the same grind size and weighed out in the bowl to be tested to an exact measurement of 10.00 Grams.
Cupping Spoon Used for All Tasting: Origami Ceramic Cupping Spoon
Grinder Used: Pietro w. Pro-Brew Burrs
Grind Size: 500 Microns
Cupping Parameters:
10.00 Grams of Ground Coffee
180ml of Boiling Water
Saturate the grounds in a circular motion to 100ml
Center Pour to 180ml
At 4 Minutes Break the Crust and Smell/Skim the surface with two spoons twice to remove remaining oils and grounds
7 minutes first taste - 9 minutes second taste
The Results:
If you are a large roastery you may have to purchase a large amount of bowls, price is a factor that plays into which bowls you may opt to purchase!
Differing weights for different materials. As can be seen the differences between glass and ceramic is minimal, but the plastic bowls are FAR lighter than their counterparts.
Each vessel has a different volume, we wanted to show the maximum capacity of each. We have a standardized cupping test, but keep in mind the differences in sizes may things.
This is meant only as a demonstration of thermal stability between the cups, we added 180ml of 100 C Water to each and took temperatures at 1, 3, 5, 7, and 10 minutes.
Thermal stability would be impacted by the added mass of the ground coffee, so we wanted to demonstrate this here. Keep in mind at 4 minutes we broke the crust with 4 sweeps, and then skimmed twice, this would impact thermals, as well as the tasting at 7 minutes and 9 minuters.
Final Thoughts:
Once more I find it crucial to understand that these results are from SUBJECTIVE tasting, smelling, sipping, and slurping on MY part, if this test was conducted by another person I believe the results would most likely be different, how different? That is impossible for me to say.
Here are my relevant thoughts:
1. Materials
The plastic bowls both imparted a flavour all their own, the Barista Hustle Cupping Bowl was far less noticeable than the generic plastic bowl (which was rated for high temperatures but I believe this may not be the case as the off flavours were very noticeable and offputting). With the Barista Hustle bowl it was possible to identify the imparted flavour, however I will say I have used Barista Hustle bowls during the life of this company, and because of only using this bowl I had not noticed this off note, and as such it may have caused skewing of my assessments of coffees, or, perhaps, I unconsciously noticed it across many coffees and eliminated it from consideration, there is no way to know as a human’s memory of a taste is imperfect, and cannot be trusted.
The Barista Hustle bowls are still good so long as the cupper is aware of that imparted flavour, and can consciously eliminate it from consideration when conducting their cuppings.
The ceramic bowls scored unevenly as the chart shows, I believe this has to do with thickness of material, as well as geometry, which we shall cover next.
2. Geometry
I believe what this experiment revealed that more important than material type is bowl geometry. The bowls that had narrow bottoms in a sort of rounded cone shape, instead of completely flat bottoms as is traditional in bowls, generally scored higher than the more flat bottomed bowls. I hypothesize that this is due to how quickly and forcefully the grounds are saturated. In the V shaped bowls the grounds were forced together and were saturated by the water stream quickly, whereas the flat bottomed bowls spread the grounds out and their saturation took longer, and may not have been as even during the initial pour. This should be researched more but is beyond the scope of this experiment, where we only wanted to see if there is one cupping bowl, or type of cupping bowl, that reigns supreme.
3. Conclusions
Sample size was a problem in this experiment, as I tested only 2 plastic, 2 glass, and 7 ceramic, I realize this issue, but ceramic is the most common material for cupping bowls in the industry, and as such will naturally be more numerous in representation.
This experiment set out to test whether or not different bowls would deliver different sensory perceptions of a coffee, and I feel strongly that it we have found that they do within these results. The Espresso Parts bowl came out on top in my testing, having an even material thickness, a rounded cone shaped geometry, and a gentle angle so as the opening at the top is fantastic for smell, but does not release heat overly quickly.
This will not be the final word in cupping bowls, but perhaps it will help to start a conversation amongst coffee professionals.
I hope to expand upon this experiment in the future, including measurements of extraction yield, and perhaps adding more bowls to the roster for a better representation of materials and geometries.
Feedback is welcome of course, but once more, keep it in the front of your mind, these results are SUBJECTIVE, and not OBJECTIVE. Your mileage may vary, the only conclusion we can draw is there is a difference in sensory experience between different bowls, and that will impact scoring, whether negatively or positively it is impossible to predict cupper to cupper. The best option for the industry is for professionals to pick the cupping bowls they feel are the best, and always use those, otherwise you introduce an uncontrolled variable to your cupping.
Thanks for being our neighbours!
