Shawn Steiman - The Little Coffee Know-It-All: A Miscellany for growing, roasting, and brewing, uncompromising and unapologetic

The scientific method involves learning about a topic, generating a hypothesis, testing the hypothesis, analyzing the results, and drawing a conclusion. This is all done as objectively as possible and according to rules and principles that allow others to scrutinize the process. Science, at its core, is about capturing variation and understanding that variation mathematically. In the natural world, there is variation: Human height varies, leaf weight varies, color varies, sugar levels vary. By examining many randomly selected individuals in a population, you can get a sense of what the average value for a trait is within that population and how much variation (distance from the average) exists. The more individuals you measure, the better youll understand that population. As an example, measuring the heights of ten people and averaging them will probably give a poor value for average human height because the variation will be so large. But measuring the height of 1,000 people will produce much more accurate values of the variation and the average.

Ultimately, scientists ask the question of whether two populations are the same or different. They do this by measuring the average values for a trait in each population and then calculating how much the variation overlaps between the two populations. Depending on how much overlap exists, the populations are considered different (although, different is never absolute; scientists always calculate a probability of making an error). All of this calculating is done using the mathematical field of statistics. Often, scientists create the different populations they are interested in studying. They may add fertilizer to one field but not another or give three groups of dogs different levels of medication. They strive to control all the sources of variation that might influence the populations so that when they finally measure what theyre interested in, the difference between the populations is a result of their manipulations, not an event related to something else.

Limitations of science

The scientific method isnt perfect because the world is not simple and scientists arent perfect. They are human, after all, and prone to all the blessings and curses that entails! There are all kinds of reasons why an experiment may not produce answers that make sense or why one experiment contradicts the results of another experiment. Some experiments, for example, may not be designed and executed well. In other cases, scientists may make mistakes, sources of variation can be difficult to minimize, and some situations are so complex that the experiment may not be able produce unambiguous data. Moreover, complex situations often require the expertise of specialists from different scientific fields or the use of technologies and techniques that arent yet perfected, none of which may be available to every research team because of resource constraints (time, money, personnel).

So, science isnt perfect. Still, it has a proven track record (cell phones, vaccines, and space ships are some good examples), and it can help us better understand the world around us. The following pages rely on science, with all its beauty and imperfections. Youll discover that scientists havent answered all the questions we will be exploring or they havent answered them very well and, often, well have to make some educated guesses to fill in the holes in our knowledge. Ill attempt to be as accurate and transparent as possible, but we may learn something new tomorrow that will make what Ive written today invalid. Please, bear with me. After all, Im just a scientist!

Coffee quality

Coffee quality is discussed and referred to often on these pages. However, because it is a fairly complicated topic, were not going to spend time discussing what coffee quality means, how we think about quality, or who gets to define what good and bad quality are. Instead, Im going to proffer a very simple definition that we can use throughout the book. High quality coffee is coffee that excites coffee geeks. It tends to have acidity and complex flavors that most people dont expect to taste in coffee. Decent quality coffee is coffee that tastes like coffee and not much else. Poor quality coffee has something evidently wrong with it like a moldy or sour flavor.