How Hot Should coffee be?
There has been a lot of debate about how hot coffee should be. Most coffee connoisseurs will have a number between 195 degrees F and 205 degrees F (or 90 C – 96 C). While many people feel that there is an exact temperature that will work out perfectly, and that it can vary greatly based on the roast and grind of the beans, the general rule of thumb is that the water should be hot, but not boiling.
Most people aim for 195 to 205 degrees but it varies depending on the type of coffee. Start off with ensuring the water is hot but not boiling then experiment from there
Most pod and drip style coffee makers will automatically set this temperature for you, although they may let you adjust it. Keep in mind that trying to verify the brew temperature once the coffee has dispensed to the carafe or cup will not give you the same reading as measurements done within the brew components, as the water cools on its way down, and may also cool again if the cup or carafe has not been preheated. If your machine has a warming plate, this is usually set to run at a much lower temperature than the boiler. Rest assured, temperature differences as much as 10-15 degrees F (as low as 82 degrees C) is completely normal and is not a sign of your machine not properly heating the water.
What temperature water should I actually put in my machine?
You’ve probably heard that you should only use cold water in your coffee maker. This is a good practice to follow, although there are multiple theories as to why this is, and most people are unable to taste (or even feel) a difference between a cup of coffee brewed with hot, cold, or room temperature water.
One theory states that hot water is likely to contain dissolved solids from your water heater, if you’re using water from the tap. If this theory is true, you could use a water tester to ensure that your tap water doesn’t contain any trace of these deposits, but there are very few regions with water that reads “clean” when tested with a TDS reader, even if you use only the cold water.
Theory #2 states that preheated water won’t be run through the grounds long enough to produce a strong enough cup of water. This is usually not true unless you’re using a percolator. Another theory states that there is more oxygen in colder water, which is said to bring out the flavor better in higher quality coffees. Most people aren’t able to taste a significant difference, though, so we’re not really sure about this one.
A (slightly more likely) theory states that hot water can damage the internal plumbing lines or heating system. For this particular theory, less expensive coffee makers are probably more prone to these problems, but also a little easier to part with, if anything does actually happen.
Our professional opinion? Use only distilled water that is room temperature or chilled. It probably doesn’t make much of a difference as long as the water isn’t hot, but feel free to try both just to form your own opinion!