Is Coffee Acidic or Basic?
Coffee covers a wide variety of flavors and is sometimes described as “acidic.” If you’ve ever wondered if coffee is acidic or basic, here’s our detailed guide explaining the difference and how this applies.
The Definitions
To define terms like “acidic” and “basic,” we need to dive into some basic chemistry.
Let's start with two water molecules. By moving some hydrogen atoms around, we can break the water molecules into a hydronium ion (positive charge) and a hydroxyl ion (negative charge). A substance is “acidic” when it has an excess of hydronium ions, creating a net positive charge. Conversely, a substance is “basic” when it has an excess of hydroxyl ions, creating a net negative charge.
It turns out that everyday items we consume are slightly acidic or basic in nature. Substances that are naturally acidic taste “sour,” while substances that are basic taste “soapy.” The acidity or basicity of a substance can be measured on a pH scale. A pH scale goes from 0 to 14, with 0 being highly acidic and 14 being the most basic. A pH of 7 is considered neutral, where the number of hydronium and hydroxyl ions balance each other, leaving the substance without a net charge. To illustrate, pure water and human blood have a pH of 7, lemon juice and vinegar are acidic with a pH of 2, and baking soda is basic with a pH of 9.5.
So, is Coffee Acidic or Basic?
With a pH between 4.5-5 depending on its concentration, coffee is only slightly acidic. The acidity in coffee is caused by the compounds present, such as caffeine, chlorogenic acid, cafestol, trigonelline, and kahweol.
Many factors affect the acidity of a coffee, such as:
- Altitude and shade - Coffee plants grown in high altitudes and shady areas are more acidic than those grown in other conditions.
- How the coffee is processed - naturally pulped coffee is less acidic than washed coffee.
- The species of the coffee plant - Robusta coffee has twice as many chlorogenic acids as other coffees, making it more acidic.
- Roasting - Lighter roasts tend to be more acidic since roasting duration and temperature reduce the number of chlorogenic acid levels.
- Brewing - Brewing temperature and duration both affect the acidity. Cold-brewed coffee has significantly less acidity compared to hot coffee. Coffee brewed for a shorter duration has a much higher acidic profile.
- Grind size - Finer ground coffee is much more acidic since the increased surface area exposed relative to volume leads to more acid being extracted in the brewing process.
Side Effects of Acidic Coffee
There is nothing inherently wrong with acidic coffee; however, it may worsen certain health conditions such as IBS, acid reflux, and gastric ulcers.
If you grapple with these health conditions, it is advisable to reduce your coffee intake or, at the very least, reduce your coffee’s acidity.
Still facing health problems due to acidic coffee? Not to worry, you can try lowering the acid level of your coffee.
Some common ways to reduce the acidity of your morning cup of coffee are:
- Drink cold brew instead of hot coffee. It's steeped for a longer time at room temperature and hence has lower acid levels
- Go for a coarser grind
- Choose dark roasts over light
- Go for arabica coffee, grown at a lower altitude
- Brew your coffee at a lower temperature
In Conclusion
While some like acidic coffee, it's not everyone's cup of tea. If you're one of those people, we recommend choosing the grind type as "cold brew" whenever you buy coffee. For example, you could try our signature Downtown Blend, with notes of cocoa, cedar, and lemongrass, and make some delicious cold brew.
Pro tip: Delicate notes actually come out better when the cold brew method is applied!