Making coffee is chemistry.
A transformation is happening from a green bean, getting roasted to evolve the flavours to its character at different stages and finally weld around with the various variables before reaching the cup.
A green bean can be transformed in endless ways. They contain the highest molecular amount of aromatic notes in nature. Many changes happen at variable pauses.
In the history of coffee making, many practices had evolved.
People learned that boiling water wasn’t ideal, developed to use pressure to release its essence, coffee paired with other ingredients.
In the context of espresso making, many had tried to understand the art of the transformation and vie to make the best possible cup consistently. Is that possible?
Who in the world can make the best coffee?
Where is the best coffee from?
What is the best way to drink coffee?
These questions, are never answered, as there is never a definite answer.
The definition of quality in coffee is multi-dimensional. Limited by the limits of a person’s sensory capabilities, by the drinker’s culture and expectations.
In the present day, many passionate coffee connoisseurs had tried to represent them in numbers to have a better grasp of the unknown to consolidate their beliefs. One example is measuring the amount of total dissolved solids(TDS). As many assumed, the more content released, the better the process was done. A few flaws can easily be pointed out as the TDS is directly influenced by the TDS originating from the water source. Which not only affects the amount of TDS in the result, also results in the solubility in the extraction process which again affects the outcome. The grind size, the dosage, the duration, temperature and amount are other variables that matter.
In an extraction process, things transform. Proteins and sugar change. Lipid oil releases into the cup and develops the aromatic profiles. In the full process, many good things get release. Like colloids that bind to the bitter astringent as receptors. Unfortunately, good things always run out first and the bitterness will prevail.
Scientific researches were done, by dissecting the oil in the espresso, to know the full chemistry of the output, to know how much of the beneficial compounds were released. That can’t be understood by taking the number of TDS as the figure does not reveal the details of the content.
Another fallacy in the method of using TDS is the limitation of a person’s capability to sense the enormous amount of flavours. Taste is always the king of decision. In the pursue for higher TDS, many develop the culture of overdosing and making very thick espressos. Unfortunately, it’s found that an average human’s sense can’t reach the same complexity. Instead, the overly thick body often hinders the person’s sense to feel the clarity.
If coffee is drank with the mouth than with the eyes, many may have a different definition of a good espresso. Robusta has always been given a bad name, but somehow, they are still rated fairly well in taste tests and have their own merits in their character and result. The pursue for perfect consistency will never be perfect as coffee changes all the time. From the air, from humidity, from pressure, light and temperature. Transformation happen on its own.
As a person age, his taste buds deteriorate and won’t taste the same as he used to.
The only way to know which is the best coffee is if the person likes it and there’s no measurement on its quality.