How Do Roasting Temperatures Affect the Acidity of Coffee

In honor of Science Education Day, the Koffee Kult team has decided to highlight a Koffee Kult family member for their superb science fair experiment on the affects that different coffee roasting temperatures have on the popular drink’s acidity. Did you know that coffee can be roasted at different temperatures? In fact, it can affect the taste and PH levels of your final cup of coffee.

The purpose of the experiment was to see what effect the roasting temperature had on the acidity of the coffee bean. For the experiment, Brazilian beans were used as the constant, and were then roasted at various temperatures including 400, 425, 450, 475, and 500 degrees. The coffee beans were then grinded and cupped using water with a neutral Ph. Each roast was tested 5 times and recorded (see chart below). A Ph meter was then used to measure the Ph of the coffee.

The results? How does the coffee roasting temperatures affect the acidity of coffee? Well, it turns out that the roast at 500 degrees had the least acidity. On the pH scale, 0 to 6 is acidic, 7 is neutral, and 8-14 is basic, meaning the substance is not acidic. The closer to 0 the numbers are, the more acidic the substance is. The average Ph of the roast at 500 degrees was 6.64. With 7 being neutral this was close to not very acidic. As a fun fact: most coffee roasters would never roast at a temperature over 485 because that is when coffee beans can combust.  Turns out that the higher the coffee roasting temperature, the least acidic the cupped coffee is.

DATA

 

Cup 1

Cup 2

Cup 3

Cup 4

Cup 5

410 degrees

5.2ph

5.2ph

5.3ph

5.3ph

5.3ph

425 degrees

5.3ph

5.4ph

5.4ph

5.3ph

5.4ph

450 degrees

5.6ph

5.6ph

5.7ph

5.6ph

5.6ph

475 degrees

6.5ph

6.3ph

6.3ph

6.2ph

6.2ph

500 degrees

6.6ph

6.7ph

6.6ph

6.6ph

6.7ph

 

Temperature

Average pH

410

5.26

425

5.36

450

5.62

475

6.30

500

6.64

 

It is important to know the effects of coffee roasting temperatures on acidity, because it shows the importance of roasting coffee correctly. Under-roasting coffee beans can lead to acidic coffee, which is harmful for teeth and can affect the taste of the coffee. It is important to have a good coffee roaster who knows the proper roast of a bean, or you might not get a good tasting cup of coffee. People in the coffee roasting industry can use this information to ensure they are producing what their customers want.  

From the author, Lucas Mardis: Thanks for the recognition – I am glad to be a part of the Koffee Kult family!