What Makes Coffee Taste Sour?
Imagine this: You wake up in the morning with a headache, or even worse, a hangover. The first thing you crave is a delicious cup of coffee to get you ready for the day. So you take time to get out of bed, grab your french press/start your coffee machine, and make some coffee. You take a sip, and it’s gone sour.
That’s a rough way to start the day! You wanted those sweet, earthy, chocolaty notes, and instead you taste something like spoiled lemonade. How did this happen?
Here are a few things that could make your coffee taste sour:
What makes coffee taste sour?
Coffee can have many different tasting notes, like nutty, caramelly, or even fruity. But even the fruitiest coffee should never taste “sour”. Here’s why yours might be tasting different:
1. The extraction process:
When you mix boiling or hot water with your coffee grounds to brew them, it begins the process of extracting different compounds from the coffee grounds. These compounds include oils, acids, sugars, and plant fibers.
As fats and acids are extracted first, they are the main reason for a sour taste in your coffee. Sugars come next, these balance out the acidity. Lastly, are the plant fibers which bring in the bitter taste that can also mask acidity.
So it makes sense that if you “under-extract” your coffee, meaning you don’t brew it long enough to let the sugars and plant fibers extract, the coffee will end up tasting sour. Unfortunately, it doesn't have much to do with your method of brewing, whether you use a Chemex, French press, Aeropress, etc; but has more to do with the timing. Brewing it for too long will make it bitter, brewing it for less time will probably leave it sour and flavorless.
2. Under-roasted beans:
When coffee beans are first obtained, they’re green. It takes the perfect balance of heat, air, rotation and a few other factors to turn them into the dark and delicious coffee making beans that we know and love. The browning of the beans is a result of “Maillard Reaction,” which turns the raw organic flavors of coffee beans into delicious notes by caramelizing the sugar. Thus, if your coffee beans are not roasted enough, they’ll be considerably sour.
3. Stale coffee beans
Coffee beans tend to lose their freshness and break down over time. As the oils evaporate, the sugars break down and natural acids turn sour. This is why coffee is best consumed freshly roasted. Just 3-4 weeks after roasting, coffee starts to taste less balanced. And a few weeks after that, the beans become sour with notes of lemon and citrus.
Ways to fix sour coffee
Let's talk about ways to fix your coffee:
1. Grind:
If your coffee grounds are not fine enough, under-extraction may occur. This is because water takes longer to fully saturate larger coffee particles leading to less flavor extraction. With finer grounds, the flavor compounds can all shine through.
2. Brewing time:
Sour coffee is usually the result of a short brew time, as the sweet flavors are not fully extracted from the bean. Hence, increasing the brew time will allow for the sweet and earthy notes to be fully extracted into your coffee.
For example, if you’re using a French press or Aeropress, you can try waiting a bit longer before slowly plunging your coffee grounds. This way you’ll be extracting more flavors from your coffee grounds.
3. Coffee to water ratio:
Using too little water can result in a potent or concentrated cup of coffee that tastes extra sour. Try increasing the amount of water you’re using to brew your coffee as it’ll result in a more even extraction with mild acidity and more sweetness.
Coffee brewing can be an art form
These solutions can all help you “fix” a sour cup of coffee. However, if you're finding that your coffee is too bitter, there are solutions for that too! We all deserve a well-balanced cup of coffee, and here at Bean & Bean, we’re all about making each and every cup of coffee shine!
More Bean & Bean Content
- 10 Ways to Make Coffee Less Bitter
- How to Taste Coffee Like a Pro
- How Do Coffee Beans Get Their Flavor?
- What Roast Dates Tell You About Your Coffee