Why Does My Coffee Taste Sour? How to Fix It

Koffee Kult coffee should never taste sour when brewed properly. We use the best specialty-grade coffee beans from around the world to ensure a balanced, delicious cup every time.

If your coffee tastes sour or acidic in an unpleasant way, it's due to under-extraction during brewing—not the beans themselves. The good news? This is easy to fix!

What Causes Sour Coffee?

Sour coffee is a sign of under-extraction, which means water didn't pull enough flavor compounds from the coffee grounds. This leaves you with sharp, acidic, unpleasant sourness instead of the bright, sweet acidity that makes great coffee special.

Three main culprits cause under-extraction:

1. Grind Size Too Coarse ⚙️

The Problem:
Grinding coffee too coarse causes water to flow through too quickly, not extracting enough flavor.

The Fix:

• Use a finer grind for your brewing method
• Different methods need different grinds:
  • Espresso: Very fine (like table salt)
  • Drip/Pour-over: Medium-fine (like sand)
  • French Press: Coarse (like sea salt)
• Adjust one setting finer at a time and taste the difference

Pro Tip: Invest in a burr grinder for consistent particle size. Blade grinders create uneven grounds that extract poorly.

2. Brewing Time Too Short ⏱️

The Problem:
Water contact time dictates how much flavor is extracted. If your brew is too fast, it will taste sour.

The Fix:

• Pour-over/Drip: Aim for 3-4 minutes total brew time
• French Press: Steep for 4 minutes before plunging
• Espresso: Target 25-30 seconds for a double shot
• Cold Brew: Steep for 12-24 hours

If water flows through too quickly, try a finer grind or adjust your brewing technique to extend contact time.

3. Water Temperature Too Low ?️

The Problem:
Cold or lukewarm water can't extract coffee properly, leaving you with sour, weak coffee.

The Fix:

• Use water between 200-205°F (just off boiling)
• If you don't have a thermometer, bring water to a boil and let it sit for 30 seconds
• Never use water straight from the tap without heating
• Pre-heat your brewing equipment to maintain temperature

Too Hot vs. Too Cold:

• Too cold (below 195°F) = Sour, under-extracted
• Too hot (above 205°F) = Bitter, over-extracted
• Just right (200-205°F) = Balanced and delicious

The Most Important Factor: Water Quality ?

Coffee is 99% water—water quality matters tremendously!

Use filtered water for best results:

• Tap water often contains chlorine, minerals, and impurities that affect taste
• Distilled water is too pure and makes flat-tasting coffee
• Filtered or spring water provides the ideal mineral balance

Signs your water is the problem:

• Coffee tastes off even with proper brewing technique
• You can taste chlorine or metallic flavors
• Inconsistent results despite following all other steps

Quick Troubleshooting Guide

If your coffee tastes sour, try these fixes in order:

1. ✅ Grind finer - This usually fixes most sourness issues
2. ✅ Check water temperature - Use 200-205°F water
3. ✅ Extend brew time - Slow down your pour or steep longer
4. ✅ Use filtered water - Eliminate water quality issues
5. ✅ Measure your coffee - Use proper coffee-to-water ratio (1:16 is a good starting point)

Coffee-to-Water Ratio Matters Too

Under-extracted coffee can also result from using too little coffee:

Recommended ratios:

• Standard strength: 1:16 (1g coffee to 16g water)
• Strong: 1:15
• Weaker: 1:17

Example: For 500ml (about 17oz) of water, use 31g of coffee (about 2 tablespoons per 6oz water)

What About Naturally Acidic Coffee?

Some coffees have bright, pleasant acidity that's different from sourness:

Good acidity (desirable):

• Crisp, clean, fruity notes
• Reminiscent of citrus, berries, or wine
• Balanced with sweetness and body
• Common in African and Central American coffees

Bad sourness (under-extraction):

• Sharp, vinegary, unpleasant
• One-dimensional tartness
• No sweetness or balance
• Leaves your mouth puckered

If you prefer less acidity, try our darker roasts like Thunder Bolt or Road Dog, which have lower acidity naturally.

Still Having Issues?

If you've tried all these fixes and your coffee still tastes sour, we're here to help!

? Chat with our AI Coffee Expert
Get instant brewing troubleshooting: Ask our AI chatbot

? Email our team
customerservice@koffeekult.com - Include details about your brewing method, grinder, and coffee

? Call us
(954) 962-2353