Brewing Coffee (a Framework)

( ... with notes on grinding, brewing and tasting coffee) updated 9/22/09

Factors for Brewing the perfect cup of coffee...

There are a couple of factors that are fundamental to good brewing that cannot be overlooked; clean brewing equipment and correct dosing (the ratio of water to coffee) are crucial. Without clean equipment and correct dosing, none of the rest of this information makes any sense!

Step 1: Clean Brewing Equipment. The buildup in your coffee-making equipment does not add to your coffee's flavor (no matter what Grandpa says); it sours it. Lime scale buildup in a coffee maker reduces the temperature the machine can attain. It coats the heating coil and the thing may never get hot enough. The case is also is true for espresso machines. For both we recommend Urnex Cleancaf. A good rule of thumb is if you smell an odor from your coffee making equipment; clean it. If you can not remember the last time you cleaned your brewer; clean it. If you get a funky cup, check that all your equipment is super clean. If you are over- or under-dosing the coffee, no amount of fiddling with extraction time will correct this.

Step 2: Use enough coffee, and don't use too much! The rule is 2 level tablespoons for a 5-6 ounce cup. Who drinks a 5-6 ounce cup of coffee these days? Well, actually I do. But my point is this: most people skimp. When you calculate that a cup costs pennies, it's really not worth your time and effort to skimp. On the flip side, if you use too much coffee, the flavor and body become unpleasantly strong, and syrupy. And adjust this ratio to your taste - I like one coffee scoop to 5 ounces - Maria prefers a weaker brew, more like one scoop to 7 even 8 ounces of water. Believe your own senses.

Step 3: Extraction. The following three factors are elements influencing extraction; these variables effect all types of brewing and need to be held in concert. As one element changes, you may need to make adjustments in the others. You cannot overdose or underdose to correct extraction problems (bad grind or low water temperature); it only makes weaker or stronger under- or over- extracted coffee. My thinking on brewing coffee has taken a big leap forward recently due to further study and a nifty handheld refractometer that measures soluable solids. I posted some videos on using this on the Sweet Maria's blog. The three factors that influence coffee extraction are:

• Grind. In grinding you are essentially exposing the surface area of the bean to water. Water is a solvent, and the longer and more contact it has with the coffee, the more it will extract. The degree of roast and the freshness of the beans impact how the beans will grind too; for example, a dark roast is more brittle and will crumble more; a dark roast can tend toward overextraction for this reason.
• Water Temperature. As mentioned above, water is a solvent and it is more active when hot, i.e. hot water extracts more quickly than cold water. More extraction = more flavor (in general; too much extraction leads to bitterness). Ideal water temperature for brewing is 195 to 202 degrees. Bring your water to a boil, wait at least 30 seconds, and brew. You can use a pot on the stove or an electric kettle can be more convenient. What is crucial is what happens once the water hits the coffee; does it cool off rapidly as in a single-wall French press or plastic filtercone? Finding ways to conserve the temperature of the water (pre-heating the French press, wrapping it in a towel, can help give you better extraction.
• Extraction Time. In some brewing methods, you control extraction time only indirectly; for example in a standard filtercone your only way to slow extraction time is to use a finer grind. Extraction time will vary based on the two other factors - say your grind is a bit too fine because you have a dark roast but you live at altitude and water boils at a lower temperature. Shortening or lengthening extraction time can compensate.

Let's take a few examples: 1) French press brewing. A French presses generally lose a lot of heat so you can end up with under-extraction. Adding more coffee (increasing the dosing ratio) just means you get stronger under-extracted coffee. Pre-heating the press and/or using and an insulated or double-wall french press can really help with heat loss and hence improve extraction. With a longer extraction time, you then need to adjust the grind coarser.

2) Standard filtercone brewing. Here you have no direct control over the extraction time; the only thing you can do is choose a finer grind so that coffee flows through the filter more slowly. Using more coffee will only help slow the flow of water through the filter, so in a way it may help improve extraction time, but it is just a question of the mass of coffee grounds. Preheating the filtercone and covering the filter helps with heat loss, but generally coffee flows through so fast heat loss is not much of an issue.

The ideal grinding practice is:

• Grind immediately before you brew.

• Adjust grind to brewing method. As noted above, using a French press means that your water temperature plummets drastically, so you need to infuse for long. That means using a coarser grind so you do not get over-extraction. With filter drip, you want to grind fine enough for good flavor extraction and to slow the flow of water through the grinds (one of the only ways to control extraction time), but you do not want the filter to clog completely and the water to pool. if using a presspot, releasing too much sediment into the cup.

• Use a good grinder. While the "whirley blade" type home grinder has helped people like me to grind right before I brew, it does not produce the best results. The whirley blade smashes the bean to bits by rotating at high speeds. The results are an uneven grind: boulders, rocks and powder. Powder clogs the filter, and boulders don't release all their potential contents into the brew. It is also difficult to reproduce the same results with the whirley blade. That said, here's the positives: they are cheap, they last, and they actually are a good match for paper filter brewing (especially Chemex) which catches all the powder. They are also pretty good for Turkish coffee ... a brew method where you want 100% powder!

Coffee Brewing Tips:

Here are a few more general brewing observations:

• Choose the brewing method that is right for you! Don't let anyone (including me!) tell you that you're missing out on something if you don't try XYZ method. If you are happy with your brewing method, stick to it! For example, a lot of people who like filter drip coffee try French Press and find there's too much sediment in the cup. It's true! You can use a Nylon Filter Screen and upgrade to a better mill, but you are always going to get a bit of turbid grinds in the cup. After all the point of French Press is to have more coffee solids in the cup - and that means, that after the coffee sits for a while, what you have is: mud. I personally don't mind. I also enjoy pour-over brewing because it gives you great control of the drip, and you can be sure the water is hot enough since you boil it yourself. In the warehouse, where time is of the essence, we use a Technivorm brewer which consistently delivers water to the grinds at the right temperature. My favorite method of all is Vacuum Brewing, when I have the time. It creates a very clean cup of coffee. Of course, one man's "clean cup" is another man's "weak", so you need to find the type of brewing that is best for you.

• Don't use cheap paper filters ...there is a difference. I feel that the Filtropa filters allow me to grind my coffee finer without clogging. Mellita is OK. Cheap filters clog easy, forcing you to grind coarser, use more coffee and detract from the resulting body of the coffee as well as flavor. I do like SwissGold filters and feel I get a little more out of the coffee with them, but I don't think they are the solution for everyone and they keep eliminating sizes, so they fit fewer brewer models. Swissgold filters let a little more sediment through and they are not as good with Whirley-blade type grinders as a paper filter.

• Use good clean water... it is extremely important! We are satisfied with city water run through a series of 2 carbon activated filters. It removes chlorine taste and other bad odors but retains the minerally taste of the water. We don't recommend soft water or distilled water. The goal is this: good tasting water with minerals. The ideal brewing water is bottled spring water but unless your tap water is unpalatable, spring water is too expensive an alternative. Water can ruin your coffee! Soft water can make all coffee taste dull, effectively muting the good bright flavors in a cup. The fact is that you could take a sample of your favorite, fresh home roasted coffee to cities around the US, and get a different cup in each and every location! Its a very disturbing thought to those of us who want to get the most out of the coffee we roast.

• Make more: For a somewhat mysterious reason, filter-brewed coffee tastes better the more you make. Ever notice how the coffee from big gas-fired urns at a cafe tastes better than the same coffee you brew at home? Strange! As a side note, I am upset that so many cafes have gone to systems that brew coffee into a pump thermos. The coffee isn't as good as that made in 2-3 gallon urns. Period! Coffeehouses are doing this because they are offensively frugal, and they want to offer mocha-berry-crunch flavored coffee along with ten other kinds. A conscientious coffee house makes coffee in big urns, and dumps what it cannot sell once an hour.

• Coffee is fresh for 10 minutes or less. Most people know that coffee tastes bad when its boiled, or left on the burner too long. I guess these thermos-pot people don't realize it stales when held at temperature by ANY method for too long.

• Take time each day to enjoy a good cup of coffee!
  - Maria

A Tip on Tasting Coffee

I hate to tell someone how to taste their coffee. You taste what you taste, you don't taste what you don't ... nobody should dictate what the experience is. Nonetheless, let me make a suggestion that will make you look ridiculous but helps me greatly expand the ability to taste coffee: CHEW IT! I am serious. Take a swig of coffee once it has cooled a bit, then pretend it is like a solid food in your mouth ... chew it twice and then let it leave your mouth (swallow or spit). What this does is circulate the coffee around your palate and makes it leave your mouth a bit slower than it would otherwise. It's amazing how this increases your ability to distinguish flavors and to pinpoint WHERE in your mouth you sense it.

You can find an adaptation of the professional coffee cupping method for home use in Ken Davids book Home Coffee Roasting. You can also cup by simply brewing 2 coffees in small French Presses or drip filters and tasting them side by side. Tasting different coffees like this will educate you more about coffee flavors than any expensive sensory training tool you can buy!