I’ve been a coffee afficianado (some would say “snob”) for about the last 50 of my 70+ years on the planet, and I would like to think I’ve
learned a few things about the subject. The two main things about making really good coffee is to start with really good beans, and use roasting and
brewing processes that don’t do any damage. (Like the motto of doctors, “First, do no harm”.)
The first and most serious way of doing damage to the brew is to cook it. The classic American percolator from the 1950s and 1960s is probably the
biggest offender in this regard. A percolator works by flashing a little bit of coffee that’s in contact with the bottom of the coffee pot into
steam. That steam drives a little column of hot water up the percolator tube and distributes it over the ground coffee, where it extracts the soluble
components from the grounds. The problem is that when the coffee at the bottom surface of the pot flashes into steam, the soluble components in the
liquid momentarily dry out and scorch. The scorched solids then get re-dissolved into the liquid and this process continues as long as the pot
percolates. This ends up driving off many of the volatile aromatic compounds in the coffee and introducing a godawful mix of random, long chain
hydrocarbons into the brew. Coffee pots like Mr. Coffee and others that keep reheating the brewed coffee for long periods of time also do the same
thing, just more slowly. Ideally, coffee should never be re-boiled after it has passed once over the grounds.
The brewing methods that do the least damage to the brew are those that boil the water BEFORE (not while) bringing it into contact with the grounds
and keep it in contact only long enough to extract the readily soluble flavor and aroma content of the grounds. (Caffeine is a relatively poorly water
soluble alkaloid, so the longer you keep the hot water in contact with the grounds, the more caffeine you will probably extract). A simple filter cone
pretty much fits this description EXCEPT that the filter paper can selectively remove some of the flavor and aroma content and also impart some paper
taste, itself. A coffee press (French, or otherwise) is basically a good choice because it doesn’t necessarily impart any off flavors during the
brewing process. Another, equally good choice is the little stove top espresso coffee makers that are everywhere in Europe. They have a chamber at
the bottom that contains only water. When heated, the water builds up steam pressure and forces the hot water up through a stainless steel mesh and
through the grounds, and then collects the coffee in a pot on the top. The whole process only takes a couple of minutes and is usually the way I
spend my first two minutes of the day, after I stagger out of bed.
Another important factor is the roasting process. When green coffee beans are roasted, the steadily increasing temperature creates increasing
concentrations of flavor and aroma compounds through organic chemical processes known as Maillard reactions. I remember reading somewhere that if you
take high quality wine and put it through a gas chromatograph, you can detect something like 300 different organic molecule species that contribute to
the flavor and aroma. Fresh roasted coffee can have twice as many identifiable species, so the possibilities for subtlety and complexity are actually
greater for coffee than for wine. However, if you roast the beans beyond a certain level of darkness, you start oxidizing the flavor and aroma
content that you created in the early part of the roasting. If you take the roasting process to the extreme, you basically end up with a bunch of
tiny little charcoal briquets which, in my opinion, don’t taste very good. When the gourmet coffee craze started taking off in the US in the late
60s and 70s, gourmet coffee (produced with commercial espresso machines) became associated with the Italian and Viennese dark roasted beans that were
common in Europe at the time. In my opinion, that was unfortunate, because the method used to brew coffee is entirely independent of the darkness of
the roast of the beans. Yet, to this day, if you go to one of the megachain houses like Starbucks and order an espresso drink you will get a drink
that is much less flavorful than it could be because it’s made from highly carbonized beans. (Although, Starbucks has started to see the light and
is offering espresso drinks with “Blonde” coffee roasts at some locations. “Blonde” simply means that the beans are not roasted as dark).
About 5 or 6 years ago I became so ticked off about the general lack of lighter roasted coffee that I bought a little table top roaster and started
roasting green beans to my own tastes. It’s worked out quite well, and it makes a fun little hobby. In the modern age of the interweb, it is easy
to get high quality, single variety green beans from practically any coffee growing region of the planet. I frequently use CoffeeAM, a specialty
supplier based in Canton, Georgia.
About decaffeinated coffee: All varieties of coffee beans start out with caffeine in them; some varieties more than others. Decaf coffee is produced
by solvent extraction of the caffeine from the green beans, before they are roasted and ground. The trick is to extract the caffeine molecules
without extracting the flavor elements. The first commercially successful process (invented in the 1800s) used Benzene as a solvent. It worked OK
but after Benzene was generally recognized to be a carcinogen, there was high demand for a process that didn’t use dangerous chemicals. The most
common process today is the so-called Swiss water extraction method. The way it works is that they take a batch of green coffee beans and soak them
in water until the water has absorbed more than 97% of the caffeine. That water will also have extracted most of the organic compounds that will end
up creating the flavor and aroma of the coffee after it is roasted, so they throw that batch of beans away. They then soak another, equal sized batch
of beans in the same water. The water cannot extract any more flavor compounds from the new beans, because the water is saturated with those
compounds, but it can continue to extract caffeine, which is present in much lower concentration. So, you end up with a batch of beans from which
almost all of the caffeine has been extracted and practically none of the flavor compounds have been extracted. You can then roast the beans in the
usual way. However, the cost of this is that you have to discard half of the beans you started with. This is why good decaf is about twice as
expensive as the same caffeinated beans. The company I mentioned—CoffeeAM—supplies both regular and decaf high quality beans, pre-roasted and
green. There’s another company based in Colorado called Blue Spruce Decaf Coffee Co. that specializes in supplying only high quality decaf beans;
you might give them a try.
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Flyingclaydisk