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What Causes Sour Espresso Shots?

We’ve all experienced those bad coffee days when we're excited about our espresso but it turns out to be bitter, sour or burnt. Espresso should be deliciously rich and smooth and have an intense flavour and aroma. 

In order to avoid sour espresso, you must know what causes it. Keep reading to learn what causes a sour tasting espresso so you never have to worry about this issue. 

Why Does Coffee Taste Sour? 

Espresso flavours that are sour, bitter and burnt are mostly caused by over-extraction and under-extraction.

When coffee is over-extracted, it overcooks and releases undesirable qualities, turning your coffee harsh, bitter, and burnt. Under-extraction results in weak and sour espresso flavours because not enough of the pleasant flavours make it into the cup. 

Therefore, it is crucial to find the ideal brewing time if you want an espresso shot that tastes nice and smooth.

The sour flavour in coffee is also caused by the tannic acid in the coffee bean. Tannic acid accumulates in the bean's outer skin. Tannic acid must be extracted at greater temperatures and pressures since it is located in a harder section of the bean. 

The longer the extraction time, the more likely that bitter tannic acid will pour into your cup. When tannic acid leaks through, the crema will have a visible lighter brown colour rather than a rich thick crema.

Espresso: Bitter vs Sour 

espresso bitter vs sour

Espresso can be sour and bitter at the same time, although they are both caused by different reasons. 

What Causes Bitter Espresso? 

  1. Wrong grind: You need a fine grind when producing espresso. A coarser grind will result in coffee that tastes bland and lacks richness. Your coffee grind should be slightly finer than salt.
  2. Poor quality: Low-quality beans will produce a bitter espresso flavour. 
  3. Wrong ratio: Espresso that is made with little coffee will be diluted and watery. On the other hand, if you use too much coffee, the espresso will taste burnt and bitter.
  4. Brewing for too long: An espresso shot will turn bitter if it is brewed for too long.
  5. Temperature is too hot: Overly hot water can result in a bitter espresso taste. Keep your water at 90°C to 96°C for the ideal coffee flavour. 

What Causes Sour Espresso? 

Did your coffee pour too quickly? This seems like an under-extraction situation, which can produce sour espresso. Here are a few reasons why your espresso shot is too sour: 

  • Inadequate tamping will result in uneven extraction and a sour taste. 
  • You might not have enough coffee in the basket. 
  • Your coffee is too coarse. 
  • Bad quality of coffee beans or stale

How to Make Espresso Taste Smooth

You need high-quality beans and the right grind size to brew smooth espresso with delectable flavours and aromas. Make sure your machine is clean as this is also a very important factor when making coffee.

Are you trying to find the best coffee beans to prevent sour espresso? Try our Primo Espresso Tazza Doro, which translates to "the golden cup". These Arabica coffee beans will produce a flavourful experience that begins with the aroma of sweet peaches and progresses toward subdued overtones of Brazil nuts.

Solve your sour espresso issues with the right beans today!

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