Is there one 'correct' temperature for brewing coffee?

First things first. The question of what is the correct temperature for brewing coffee is a bit misleading because there is no one correct temperature for making a great cup of coffee. We’re sure you may have heard that using boiling water ‘burns’ coffee or that you should use water just off the boil when making your morning brew. Are these statements true? Yes and no, and the long answer is a little more complicated.

If you’ve stopped by this article for a quick answer, you can aim for somewhere between 90-96C (that’s 195F-205F in old money). This should serve you well for most roasts.

If you’re like us and like to get a bit technical, understanding how you might even want to adjust your brew temperature depending on your coffee of choice, you’ve stopped by the right place so read on!

A brief dive into the Science of Water Temperature and Coffee 

We mentioned earlier the common saying that boiling water will ‘burn’ coffee. You may have even had a coffee that tastes bitter and acrid like it has been burnt. What has likely happened here is that your coffee would have been over-extracted.

This term ‘extraction’ is crucial.

Roasted coffee beans contain a number of different compounds that lend different flavour profiles. Fruity and acidic compounds are extracted first, followed by sugars which add sweetness to the cup, and finally compounds that give coffee that distinctive bitterness.

The correct water temperature is needed to extract these flavours in the most s and boiling water may over-extract flavours, particularly bitter ones. Over-extracted coffee isn’t really ‘burnt’ during brewing because during roasting beans are often exposed to temperatures of +200C.

Conversely, if water temperature is too low the taste may be underdeveloped and sour (and under-extracted) because the sugary and bitter compounds weren’t dissolved.

This brings us back to the 90-96C window we mentioned earlier. For most coffee, using water temperature somewhere in this range should give you a well-balanced, and well extracted cup of coffee. To achieve this, leaving your kettle for 30-60 seconds after boiling should suffice. However, you still might want to make some changes depending on the roast profile of the coffee you are brewing. 

Lighter Vs. Darker Roasted Coffee

Roast profile matters when selecting the optimal brewing temperature. This is because coffee roasting initiates cellular changes in coffee beans, and the longer the roast (and therefore darker the coffee) the more the cellular structure of coffee beans has been broken down.

What this means for your coffee brewing is that darker roasts are generally more porous and contain more easily dissolved soluble than lighter roasts. You’ll want to lower your water temperature to around 90-93C.

In contrast, light roasts have a more intact cell structure which is less porous, meaning those compounds that add flavour to your coffee are less easily dissolved. We recommend a higher brew temperature of 95-97C.

In summary

• Lighter roasts: 95-97C (203F-207F)
• Darker roasts- 90-93C (194-200F)
• For medium-dark aim for somewhere in between around 93-95C (199-203F) 

 Brew method

We thought it would be important to note adjustments you might want to make based on your coffee brewing method.

Using the temperature margins above, aim for the lower end if you’re using a pressurised brewing method (such as an AeroPress or espresso machine). This is because pressure helps in extraction, and a slightly lower temperature adjustment can help to compensate for this. 

If you’re using a V60 or pour over you’ll lose the added benefit of pressure, and might want to aim for the higher end of those margins. Also note that you can alter the extraction speed by using a slow or fast pour.

Finally, if you love your immersion-based coffee (most commonly cafetiere) remember that the coffee generally has a longer brew time and you can therefore adjust your temperature to be slightly lower.

Helpful gadgets

Here at Redber we’ve not only got an extensive range of single-origin coffees, blends, and roast profiles to choose from but also a wide variety of coffee equipment and brewers to allow you to do your own research.

If you’re really wanting a great brew, consistent every day, consider checking out this electric temperature-controlled kettle by Felicita. Alternatively, as a budget option you can check out our range of barista thermometers to help you experiment! These are generally used for barista drinks but can also be used to find the best water temperature for your brew. We recommend boiling water in your kettle as normal, decanting into a heatproof jug (such as Pyrex), and simply waiting for the water to reach the right temperature, then brew!

Some coffee suggestions from us at Redber to get you started

Ethiopia Sidamo Medium Roast- A good starting point if you're new to lighter roasted coffee. Ethiopia Sidamo has tasting notes of tea and lemon, with a citrusy-cocoa aroma. For medium roast, try brewing 95-97°C.

Peru Tapir Andino Red Honey Medium-Dark Roast- This stunning honey processed coffee from the protected San Ignacio Provence in Northern Peru delivers flavours of chocolate, mango, blackberry, & Candyfloss. For medium-dark, we recommend brewing 93-95°C.

Guatemala Antigua Dark Roast- A firm favourite among our customers here at Redber. This is a dark roasted coffee, try brewing at 90-93°C. Expect flavours of caramel, exotic fruit, and hazelnut.

Takeaways

We hope you’ve found this guide helpful, and interesting! Remember that coffee making is also about personal preference, so whilst we’ve given you some guidance to get you started, you can experiment and find what you like the most. The key takeaway from this article is bitter and ‘burnt’ tasting coffee has likely been over-extracted. Adjust by lowering your brew temperature. Acidic or underdeveloped taste is often indicative of under-extracted coffee. Adjust by lowering your brew temperature.

CM (05/08/2022)