Finding The Best Way To Brew A Cup Of Coffee Mathematically.

 

In the teachers lounge, there always seems to be a coffee maker with a pot of coffee brewing.  As soon as it empties, someone starts a new batch because teachers survive on coffee.  I am not a coffee drinker so it didn't bother me but most of the staff were into their coffee.  According to a reprint in Scientific American, someone created a mathematical model designed to determine the best way to brew a cup of espresso.  The model came out of the question on why coffee can taste different at home vs at the store, at work vs the airport.  Apparently, it came down to the brewing method.

One factor is the coffee itself because the type of coffee and it's country of origin factor into its quality.  There is also how the coffee is roasted, the water its brewed with, but the method used to brew the coffee has one of the higher effects on the end result.  The mathematical model looked specifically at espresso because it requires such precise measurements making it the most complicated to brew.  In addition, espresso forms the basis of cappuccinos and lattes.

The method used to espresso requires that hot water be forced through finely ground coffee. The amount of coffee, water, and fineness of the ground along with the water pressure, temperature, and amount of the brew are all crucial to the final product. This process ends up balancing around 2,000 chemicals to get the proper taste.  Even when things are done the same way every time, it does not automatically guarantee the same result every time.

So a group of people made up of mathematicians, chemists, materials scientists, and baristas got together to create a mathematical model to figure out the best way to produce a consistent cup of espresso at a coffee shop every single time. The model was used to predict how much solid coffee is dissolved in the final cup of coffee.  This is known as the extraction yield which is a percentage and is used in the coffee industry to assess various coffee recipes.  The object was to create recipes which produced the same cup every single time.  In other words, the flavor had to be reproducable.

Using a series of equations, they discovered that the model accurately predicts the extraction yields experienced in real life except for when the recipe used the finest coffee grounds.  This is because the water used to make espresso is forced unevenly through the coffee grounds causing some sections to become clogged thus under extracting the liquid and other sections are over extracted.  

They came to the conclusion that contrary that the barista needs to use less coffee that is ground a bit courser to get the consistently tasty results they desire.  Mathematically, using less coffee means that the water flows faster through it thus making the water flow and extraction more uniform.  The result is a fast, bright, sweet liquid that is slightly acidic every single time.  Since not everyone wants the same result, different tastes can be made by combining different brews or by changing the roast.

One thing that comes out of this model is that baristas are able to reduce the amount of coffee waste by one fourth per espresso shot which increases profit without compromising the taste. The savings could be as high as $1.1 billion a year for all cafes in the United States alone. Furthermore, since at least 60 percent of the worlds wild species are threatened with extinction, using less coffee means there is less demand and these plants have a better chance of recovering.

So now, you've learned another way people are using mathematical models to improve flavor, help the environment while saving money.  Let me know what you think, I'd love to hear.  Have a great day.