HOW IMPORTANT IS WATER TEMPERATURE TO A GREAT CUP OF COFFEE?
In our second of 4 parts, we will look at why the temperature of your water can dramatically affect your coffee enjoyment. First, a short story:
In a recent article in a national men’s magazine, a senior editor was touting the simplicity of an old style coffee percolator. I remember those coffee pots he described very well. Growing up in farm country in the Midwest, my parents and grandparents prepared their coffee in one of these. Coffee was placed in an aluminum basket that fit over a long tube. When the tube and basket were lowered into the coffee pot and placed on the stove, water in the pot boiled, flowing up the tube and over the coffee. The longer you left the pot “on the boil”, the stronger the brew. While singing its praises for the simplicity of this old coffee maker, the writer of the article went further to say he enjoyed the “mouth-scalding perfection” of the finished product and the “strong as hell” taste that came from not requiring a filter. He finished with calling out those who did not use this method as “coffee dweebs”. People who were settling for lukewarm and weak coffee. Before we unpack the reasons I disagree with him, let’s review why we are sharing this 4 part blog on coffee preparation.
Our first blog article (read it here) spoke of the importance of grind size and the consistency of that grind in setting you up for the perfect cup. Grind size varies depending on the brewing method you prefer. If brewing great coffee had just one variable, like grind, we would be done. But brewing great coffee needs to consider all the variables. And the temperature of the water is often overlooked, but ultimately important in extracting all the flavor from your coffee, no matter what the grind. Properly brewed coffee requires using the correct quantity of good coffee, ground precisely, extracted to the correct degree, controlled by the correct time and combined with the correct amount of water at the right temperature.
HOW DOES WATER TEMPERATURE AFFECT COFFEE EXTRACTION
Simply put, you can’t make coffee without water. Water molecules act like a solvent, extracting and dissolving coffees flavors like oils, fruit acids, simple sugars, and caramelized sugars. This may seem obvious, but boiling water only takes minutes to produce an extraction of these flavors, while cold water used to make a cold brew coffee can take hours to accomplish extraction.
WHAT IS THE CORRECT TEMPERATURE?
Most coffee experts believe the “goldilocks range” for water to brew with is between 195 and 205 degrees Fahrenheit. This range provides for a controlled extraction of the coffee’s flavor. Higher temperatures than 205, especially boiling water, will over extract the flavors from the grounds, producing bitter coffee. Water under 195 degrees has a difficult time extracting the coffees flavors, which often leads to sour, underdeveloped coffee. And as mentioned earlier, grind, extraction time and water volume must also be balanced with the temperature you use. More on time and water volume in the next two blog articles.
Important note-there are some coffee veterans who use lower temps for their extraction, but most of us home brewers should stick to the range above.
GETTING A CONSISTENT WATER TEMPERATURE
It’s easy to get your water temperature in a consistent place where you can “set it and forget it”. Since water boils at a lower temperature the higher the elevation, you will need to make sure to take that into consideration. At sea level, water boils at 212 degrees Fahrenheit. In high elevations, like Denver, it boils around 202 degrees Fahrenheit. Most of us are somewhere in between.
Whether you use a pour-over method, a drip coffee brewer, Aero Press or a French Press, choose the right equipment that will consistently heat your water in the 195-205 degree range. If you boil it on the stove, use a thermometer to check the temp. Here’s the bottom line. You don’t need to get the water temperature down to a tenth of a degree. Just keep it in the range and you will enjoy a better cup of coffee without a lot of fuss. For your convenience, at Arnold’s Coffee, we offer Bonavita brewers and variable temp kettles that make temperature control simple and easy.
So what about our friend in that men’s magazine? I have a feeling this article won’t change his mind. Perhaps the old school nature of that percolator is what appeals to him. Call me a “coffee dweeb” but my Arnold’s coffee deserves better treatment than a quick boil.
In our next article, we will discuss how Time affects coffee brewing.