The Heat Is On - How the Temperature of Your Water Makes a Difference
When brewing coffee, there are many elements to be aware of. Of course, the coffee beans you use are extremely important, which is why you want to have the freshest beans possible as well as the correct grind for the brew method. But did you know the temperature of your water can also make a difference?
What is the Ideal Temperature?
Cold-brew aside, when you're brewing your coffee, your water should be around 195 to 205 degrees Fahrenheit. Water typically boils at around the 212-degree mark (altitude may affect this number, so your mileage may vary). It is considered customary to use water that is just off the boil. This means you should let the water sit for about a minute before pouring it over your coffee grounds.
Drip machines, single-serve machines, and espresso machines are all calibrated to brew using the correct temperature. When making French press or pour-over methods, you might want to use a thermometer to know when your water is the ideal temperature. Or, again, just wait about a minute after your water has come to a rolling boil.
Why Does Temperature Make a Difference?
When brewing coffee, the hot water extracts the flavors from the grounds. When your water is not the correct temperature, it won't extract correctly, and your coffee can taste off. When your water is too cold, it won't pull enough flavor from the grounds and will make your coffee taste weak and possibly sour. When your water is too hot, it will over-extract the flavors and make your coffee taste bitter. Nobody wants weak or bitter coffee.
How Can I Be Sure My Water is the Correct Temperature?
It's entirely up to you how exact you want your coffee brewing process to be. If you're using a machine, you don't have control over much of the process to begin with. Maybe warming up your mug prior to hitting the button on the single-serve or possibly pre-heating the carafe before beginning the brew process with your drip machine.
If you are doing your own pour-over or using a French press or maybe an Aeropress and want to know your water temperature is in the sweet spot between 195 and 205, a good quality thermometer might be a worthwhile purchase. If just being in the ballpark is good enough for you, remembering to let the water sit for a minute or so after coming to a boil may be just fine.
Other ways to control the temperature of your water can include warming up your vessel (either mug or carafe) before starting your pour-over. When using a French press pre-heat your carafe first so the water doesn't cool off too quickly. The best way to heat up your vessels is to simply fill them with hot water while your brewing water comes to a boil.
Is This an Exact Science?
No, brewing coffee is not an exact science. For example, the flavor of your coffee may be affected by not only the temperature of the water but how that temperature interacts with the roast level of your coffee beans. You might find that hotter water with dark beans makes for an over-extraction. If this is the case, try lowering the temperature of your water a little bit. On the other hand, if you have a light roast, your water temperature might need to be a little higher to pull more flavor out.
Bottom line, you will need to find out what works for you. But this when it comes to water temperature, around 200 degrees Fahrenheit is a good starting point.