Brewing Coffee 101: How to Brew the Perfect Cup
It has been said that the two most important things you can do to ensure a great cup of coffee, is to buy freshly roasted coffee beans, and then grind the beans yourself right before brewing. Having said that, you can do those two things and still end up with a mediocre cup of coffee. It all depends on how well you handle the brewing process. What I mean by this is, depending on your method of brewing coffee, you may need to alter a few things to get the most out of your cup. This is truly where the art of brewing coffee is realized.
My father often tells me that he’s always in search of the perfect cup of coffee, even though he uses the exact same brewing method every day. “Brewing coffee is half art and half chemistry - or alchemy. The exact portions of ground coffee to water, the water temperature and the water’s contact time with the grounds all affect the flavor of the final coffee. It is possible to make two very different tasting beverages from the same beans using different brewing methods or using two identical brewers and simply altering the variables with each brewer” (Sinnott, 7).
In this blog, I’ll stick to general tips and tricks you can follow, for any brewing method you choose. I’ll create other short blogs for each type of brewing process which will include tips specific to those methods, especially grind size.
Each variable is important, so it’s not easy to pinpoint the most important factor. Corby Kummer thinks that the freshness of the roast matters more than anything (Kummer, 3). While this may be true, Sinnott explains that “the most refined, seasoned experts acknowledge that a properly brewed cup of mediocre coffee tastes better than an improperly brewed cup made from the best beans” (Sinnott, 89). This means that you can purchase our excellent coffee, yet still be unsatisfied with the end product, if you use too much water, or if you leave the coffee brewing for too long, or if the grind is not the right size.
Thankfully the process isn’t too complicated, once you’re aware of a few do’s and don'ts. In fact, if you follow these steps (especially if you were making some key mistakes), you may notice a big difference in your everyday brew. You can experiment and tinker as you see fit…but once you achieve that perfect cup, you’ll want to be able to duplicate your steps so that you can reproduce that wonderful feeling every day. I’ll list out the variables below, and will explain how to bring the best out of them.
Necessities for the Perfect Cup of Coffee
- Freshly Roasted Whole Bean Coffee
- Burr Coffee Grinder
- Fresh Spring Water
- Measuring Cup (for your water) and Coffee Scoop (holding 10 grams of ground coffee)
- Timer / Stop Watch
- Brewing Apparatus (French Press / Brewing Cone / Percolator / Vacuum Pot, etc…)
Key Rule for Freshness: Purchase freshly roasted coffee from Cafe Elba, and keep it stored correctly to preserve the flavor compounds.
Believe it or not, drinking premium coffee is a fairly new historical phenomenon. When coffeehouses started opening up all over Europe in the 1700s, it was still common for roasters to roast coffee beans with all types of additives, like cocoa beans, cinnamon and lemon skins. This wasn’t done because of the poor quality of the beans themselves, but rather to add strong flavors that would survive the ancient brewing practice of boiling coffee grounds. If there’s one thing you don’t want to do, it's to boil coffee grounds (unfortunately, the widely used Percolator does just that). “Boiling coffee is the fastest way to drive off delicate aromatics, and it only heightens the bitter and sour components. Small wonder that the English, in their legendary eighteenth-century coffeehouses where essay and modern prose style were honed, laced their boiled coffee with sugar, egg yolk and all manner of strong-flavored ingredients, including mustard” (Kummer, 88).
Since the percolator was the main method of brewing coffee in the United States for most of the 1900s, coffee in this era was often bitter and bland. Thankfully, this all changed in the 1970s and 1980s, with the arrival of Alfred Peet in the Bay area, who began Peet’s Coffee and Tea company, which eventually spawned the new specialty coffee shop craze, and has transformed the way millions of people enjoy coffee.
That’s where we come in. If you order our coffee, you have the fresh coffee requirement ticked off. All you need to do is store the coffee correctly to preserve the flavors (see our blog for instructions: How to Store Your Roasted Coffee). I should also include this tip, which, as soon as I read it, realized how important it was. “Always treat your first batch of new coffee as a test batch” (Sinnott, 91).
Grinding Before Brewing Does Make A Difference!
Key Rule for Grinding Your Coffee Beans: Invest in a Burr coffee grinder, and grind right before brewing to get the most out of the coffee beans.
“The difficulties of packaging and storing ground beans to retain maximum freshness have led to the unbreakable rule that you should always grind beans at home just before brewing” (Kummer, 57). The flavor difference is very noticeable when you grind the beans at home. Don’t overlook this important step! “Grinding is critical to the brewing process. The job of any coffee grinder is to divide the beans into same-size pieces. This might seem simple, but grinders are the Achilles’ heel of many a home-brewing station” (Sinnott, 7).
There are two general grinder technologies in the market. Unfortunately, most people use what’s called a propeller grinder which grinds coffee with a spinning blade. These grinders are cheap (anywhere from $15 to $30) but will not do an adequate job. Don’t waste your money on these! Since each brewing method requires a specific grind size, “the best grinder is one that consistently produces even-sized particles” (Sinnott, 81). Corby Kummer sums up the main problem with propeller grinders: “the granules produced by a propeller grinder vary greatly in size, from the fine powder beneath the blade at the bottom of the chamber to the coarser pieces at the top. This powder, or ‘fines,’ can slow the passage of water through coffee in a filter causing bitter and sour substances to enter the brew” (Kummer, 62).
What you really need is a burr grinder (sometimes called a ‘coffee mill’). These grinds use a rotating metal or ceramic disc to grind coffee beans with much more precision than propeller grinders. “The notched metal discs of the coffee mill revolve against each other and shred the beans a few at a time. This is the same principle by which people have ground wheat and other grains for millennia, using millstones” (Kummer, 58). For more on choosing the right grinder, see my blog Choosing A Coffee Grinder.
Now that you have your burr grinder, we can look at the next variable in the brewing process, which is water. But before I get to that, I should mention that even today, coffee aficionados argue over what the best grind size is for each brewing method (Pendergrast, 387). So ultimately, it will be up to your taste buds to decide. As a general tip, I’ve read that “most novices grind too fine. Start out grinding coarser than you think you’ll need. Then move a notch at a time finer until you reach the perfect grind and taste” (Sinnott, 85).
The Main Ingredient: Water
Key Rule for Water 1: Use fresh spring water. If you like your tap water, feel free to use it. Do not use distilled water, which tastes lifeless.
Key Rule for Water 2: The water temperature should be below the boiling point, at about 96 degrees, when it comes into contact with the coffee grounds.
Since your cup of coffee is about 98% water, the quality and taste of the water you use is more important than you might have otherwise thought. It actually compliments the taste of the coffee beans. Most people don’t realize that the chemical composition of water varies from place to place. “Calcium, which comes from rocks in the ground, is the largest likely suspect. Have you heard of the phrase ‘hard water’? It usually refers to the calcium minerals within it. If the minerals in hard water are in high enough concentration, they can give the coffee a pronounced metallic taste” (Sinnott, 92). Furthermore, ‘“hard water contains alkalines, or dissolved base minerals, which can react with and neutralize the precious flavor-giving acids in coffee. Even less desirable is softened water, whose phosphates and other agents can impart a soapy taste” (Kummer, 70).
Distilled water is not the answer either, since it has absolutely no flavor, and often leads to a lifeless cup of coffee (Kummer, 69). Ideally, you want water with a neutral pH (Sinnott, 92). If you like the taste of your tap water, that should suffice. However, many people have concerns over the fluoridation of tap water. On top of that, many municipal governments “over-chlorinate to prevent contamination” (Sinnott, 92). If you find this is the case with your tap water, a charcoal filter will remove any off flavors produced by chlorine (Kummer, 70). Personally, I use natural spring / mineral water for brewing coffee.
Before closing out our discussion on water, let’s talk about the requisite water temperature right before it hits the coffee grounds. This temperature is the same no matter what brewing method you’re using. “The ideal water temperature is about 195 to 205 degrees F (90 C to 96 C) - not a rolling boil, which will extract bitter substances you don’t want to taste. Long contact time is the surest way to over-extract coffee: no brewing with hot water should go on longer than eight minutes” (Kummer, 68). If you’re using a kettle that doesn’t have a built-in thermometer, a good tip is to let boiling water rest for about 20 seconds before using it to brew coffee (Kummer, 95).
The Right Scoop Amount
Key Rule for Coffee Grounds to Water Ratio: Use two tablespoons (10 grams) of ground/whole bean coffee for each 6 ounces (180 ml - a small cup) of water. But when in doubt, use more coffee grounds.
“Roasted coffee beans contain about 30 percent soluble solids, and most experts put the ideal extraction rate at 18 to 22 percent” (Kummer, 68). While this may sound a bit too technical, what it means is that when you grind your coffee beans and pour hot water over them, about 20% of the oils and small particles of coffee solids should end up in your cup. In short, these compounds are what turn water into brewed coffee. So how much coffee grounds are required? It all depends on how much water you’re using, which in turn depends on how much coffee you want to brew. Thankfully, the ratio of coffee grounds-to-water is universally agreed upon, and applies to all brewing methods. “The recipe for making excellent coffee is well-established: two tablespoons (10 g) per six ounces (180 ml) of water. It has been documented that Ludwig von Beethoven used to count sixty beans for each six-ounce cup - which happens to equal two tablespoons” (Sinnott, 91).
Corby Kummer insists that getting this ratio correct will make all the difference. Ostensibly in an effort to help us out, many coffee equipment manufacturers include a ‘coffee scoop’ with brewing machines. The problem with these scoops is that they often only hold one tablespoon of ground coffee, instead of two. If you’ve been using this half-scoop, your brew will be perpetually weak. “So many scoops today are half-size that it’s a good idea to pour a tablespoon of water into the scoop to measure its capacity” (Kummer, 71). It’s generally a good idea to use a bit more coffee grounds than you think you’ll need. “If you prefer weaker coffee, it will taste better if you make it full strength and then dilute it with hot water or milk” (Kummer, 71). Better to have a strong brew rather than a weak one!
Keeping It Clean
As with all machinery, keeping your coffee brewers (press pot, drip machine, metal filters) and grinders clean will ensure they are in good working order.
Let’s start with your grinders. Purchase a toothbrush or paintbrush specifically for cleaning your coffee grinder. You don’t need to wet it. Just brush away any accumulated coffee grounds from your grinder. All roasted coffee beans will start to look oily after a week or two. These oils can accumulate on your grinder’s hopper (the opening where you load the whole beans), so you should wash the hopper (if it is removable) with a sponge and warm soapy water. Make sure to avoid using any scented detergents or soap, since we don’t want to add any outside flavors near your roasted coffee (Sinnott, 85). Speaking of outside flavors, you should never use your coffee grinder to grind scented coffee (this is coffee roasted with additives and flavors such as vanilla, or cinnamon). The reason for this is because the oils which produce the flavor remain in your grinder and become rancid over time. “These flavor oils stick to your grinder’s mechanism and will likely change your non-flavored beans’ taste” (Sinnott, 85). A great trick is to run oats through your coffee grinder to remove any off flavors. “They are soft enough to run through the grinder, gentle on the burrs, and absorb the flavor oils” (Sinnott, 85).
When it comes to automatic drip coffee brewing machines (the primary method of brewing coffee in North America), the problem is with water. More specifically, the issue is with the minerals dissolved in water which originate from limestone deposits in groundwater (Schwarcz, 213). “During brewing, the near-boiling water keeps calcium and other minerals suspended. Some cling to the pipes inside the coffee brewer, clogging it after a while. Water softened using salt - found in most homes and some municipalities - is more problematic. The residual salt following softening can form a gelatin-like goo in the coffee brewer’s filter, which can prevent extraction or even halt the whole process” (Sinnott, 92). Some high-end brewers are equipped with sensors that light up whenever lime or calcium builds up, but if your brewer doesn’t have that feature, you can purchase packets of cleaning powder, which should be run through your brewer once a month (Kummer, 74). “You can also use a solution of 1 part white vinegar to 3 parts water. In either case, you’ll have to run clear water through the brewer three to five times after you clean it” (Kummer, 76).
Finally, we come to the carafes, filters and other coffee accessories. Interestingly, carafes don’t need as much care as brewing machines, because the acids in coffee (which give coffee its flavor) dissolve calcium carbonate in your carafe. “Since coffee is more acidic than water, it is better at preventing the buildup of limestone scale” (Schwarcz, 214). But you should wash the filter (if you’re using a reusable filter of course) and carafe after each brew, in order to remove any built-up coffee oils and sediments. You can use warm soapy water to do this, but the problem is that many soaps are scented. A better alternative “is to use instead of soap a paste of baking soda and water, which will not leave any off flavors” (Kummer, 76).
Summing It All Up
I think Corby Kummer summed it up best when he wrote that “the best brewing method is one convenient enough for you to use all the time” (Kummer, 70). Single use coffee pods are very popular these days for this very reason. It’s convenient. But I just can’t find myself to enjoy a cup of coffee brewed this way, because this type of coffee goes against many of the instructions I listed out in this blog. The coffee in pods is usually not freshly roasted, they are always pre-ground, and you get no control of the brewing process (the temperature of the water, the right scoop amount, etc). This level of convenience strips away the art of brewing your very own perfect cup. Part of the beauty of coffee is the brewing process and the rituals that go along with it. “Brewing is not an exact science because the variables constantly change. There is no process with more possibilities and variables than brewing. Every method allows for seemingly endless tweaks” (Sinnott, 89).
Before listing out the key steps I’ve been writing about, I’ll close out this blog with the following nugget of knowledge. “The main point, regardless of what roast or origin you choose, is to get freshly roasted coffee at frequent intervals, buying only what you plan to use in the coming week or so. Otherwise, your coffee will get stale, no matter how great it was to start with” (Pendergrast, 387).
Key Steps to a Good Brew
- Purchase Freshly Roasted Coffee from Cafe Elba!
- Grind Coffee Beans in a Burr Grinder Before Brewing
- Bring Mineral Water to a Boil + Wait 15 Seconds Before Pouring Water
- Use Correct Ground Coffee-to-Water Ratio
- Brew Coffee Using Your Preferred Brewing Method
- Pre-Heat Your Coffee Mug with Hot Water, Before Pouring Brewed Coffee
- Once Brewed, Pour Remaining Hot Coffee Into an Opaque Thermal Carafe
- Enjoy the Most Naturally Flavorful Drink in the World!
- Written by Coffee Mike
I like to include the following disclaimer below each of my blogs. I try to make references wherever applicable, but I’ve read many books, dozens of articles, watched documentaries and taken courses on these subjects over the years. I mention this because sometimes I may forget the exact source of my information, so I ask the authors to forgive me if I have not cited some information where I should have.
Kummer, Corby. The Joy of Coffee: The Essential Guide to Buying, Brewing and Enjoying. New York: Houghton Mifflin Company, 1995. Pages 3, 57-58, 62, 68-71, 74, 76, 88, 95.
Pendergrast, Mark. Uncommon Grounds: The History of Coffee and How It Transformed Our World. New York: Basic Books, 1999. Page 387.
Schwarcz, Joe. Dr. Joe & What You Didn’t Know. Toronto: ECW Press, 2003. Pages 213-214.
Sinnott, Kevin. The Art and Craft of Coffee: An Enthusiast’s Guide to Selecting, Roasting, and Brewing Exquisite Coffee. Beverly: Quarry Books, 2010. Pages 7, 81, 85, 89, 91-92.