Brewing The Perfect Cup of Coffee

Although it seems very easy to brew coffee, brewing a really "good" cup is something altogether different. It's as much art as it is science, and as personal as it is universal. The most frequently asked question from returning customers is "Why can't I make my coffee taste like the coffee you have brewed in your store?" It's not that brewing great tasting coffee is exceedingly difficult, there are just a few factors that need consideration before starting. Understanding the key factors that impact coffee taste is the key to brewing the perfect pot.

So what happens when a pot of coffee is brewed? The scientific explanation is that the water extracts the water-soluble material from the coffee bean. The chemical reaction starts when the hot water wets the coffee grounds and releases the gasses that fill our kitchens with the sweet smell of brewing coffee. As water flows over the grounds, a hydrolytic reaction takes place in which the water-soluble components dissolve from the grounds into the water. These soluble proteins and sugars give coffee its flavor. Practically speaking, the factors we can control at home are: water quality, water temperature, grind size, ratio of coffee to water, and cleanliness of equipment.

Water Quality

In any recipe, the quality of the starting ingredients impacts the taste of the final product. Coffee is 95% water. It stands to reason that the better the water, the better your cup of coffee will taste. Filtered water and spring water are recommended over plain tap water because they lack the fluoride and chlorine used in water treatment that can foul the taste of the java. Distilled water is not recommended for brewing coffee as it lacks minerals that compliment the natural flavors of coffee.

Water Temperature

When considering the chemistry behind making coffee, it is understandable that the reaction has to have an ideal temperature for complete extraction of desirable components. The water should be at least 200 degrees Fahrenheit when it wets the coffee grounds. If the water isn't hot enough, complete extraction from the grounds will not take place and the coffee will end up with a murky flavor.

Ground Size

Once the water temperature is hot enough, the number one way to change the taste of the coffee is to change the size of the coffee grounds. This has to be one of the most misunderstood aspects of brewing coffee because it‘s counter intuitive. Most people believe that finely ground coffee extracted through a drip brewer produces a stronger tasting cup, but what is actually being accomplished is that the coffee will have more of a “bite.” By decreasing the grind size the surface area exposed to the water during the brew cycle is increased. This causes an over extraction of dissolvable solids from the bean, pulling undesirable bitter components out as well. Consider the following illustration:

Let’s consider the following illustration: 

Grind Size	Fine	Medium	Course
Extraction Method	Espresso	Turkish Drip	French Press
Brew Time	25 sec-3 min	4-5 minutes	5-7 minutes

In an espresso extraction method, hot water is pushed through finely ground beans at about 1.2 bar of pressure. The whole process should take 2 ounces of water approximately 25 seconds to press through the grounds. Grind size is the variable that must be adjusted to achieve this time.

In a drip extraction method, heated water is poured over medium ground coffee that is contained in a basket. The water passes through either a paper filter or a reusable gold filter. If the coffee is at a medium grind and the brew cycle is taking too long...more than 6 minutes... check to make sure the filter isn’t clogged or improperly installed.

In a French press extraction method, boiling water (212 degrees Fahrenheit) is poured over coarsely ground coffee. It is allowed to steep for 5-7 minutes, and then a filter is pressed through the pot to remove the grounds. One of the reasons a French press produces a very flavorful cup of coffee is that the water is hot enough to get complete extraction. So the longer the ground coffee is in contact with water, the courser it should be.

Ratio of Coffee to Water

The amount of coffee someone prefers to use is highly subjective. Because of this reason, combine the following information with your taste buds to produce your perfect cup. When brewing a 10 cup carafe of coffee, Mobjack Bay Coffee Roasters prefers to use 2 ounces of medium ground coffee in a drip coffee maker. One measured ounce of coffee is equal to 28.35 grams. Two ounces of coffee is equal to 56.7 grams of coffee. This translates to 5-7 heaping tablespoons (adult soup spoon) per pot of coffee. This is a great starting point in the search for your perfect cup. If you have a kitchen scale, it would be worth the effort to use it to determine how many scoops or tablespoons are needed to get 2 ounces of coffee grounds specifically for your brewing method.

Here are a couple of things to remember:

If you don’t use enough ground coffee you’ll end up with a weak and bitter cup.

Why? Water will continue to run over the grounds extracting many of the bitters out of it. If you use too much ground coffee, you’ll end up with an underdeveloped strong cup.

Why? Not enough water runs over the beans to get complete extraction, leaving many of the desirable components still in the grounds.

Cleanliness

Keeping a clean brewer is often an overlooked aspect of brewing good coffee. There are a couple of things that are very important to touch on. Cleaning any part of the coffee maker that touches brewed grounds should be done as soon as you can. Specifically, the basket and spout in a drip brewer are often neglected. If they are not cleaned, trace amounts of coffee solids are left to dry. When you brew another pot, they will add their bitters to the next pot.

Why? They’ve already been brewed once. Keeping your brewer clean is an easy step to assure a consistent cup. Decalcifying your drip coffee maker is something you should do as often as recommended by the owner's manual. If using well water you’ll want to do it more frequently. The main reason is that the heating element becomes calcified and subsequently can’t heat the water to 200 degrees Fahrenheit. If you start to lose cup quality, consider the last time you cleaned the coffee maker.