Is SOE Americano Black Coffee Too Sour When It's Spoiled? Is It Normal for Espresso Beans to Have Acidity, and What Are the Reasons?

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Why Is My Americano Sour?

"Ouch! Why is this Americano so sour? Has it gone bad?" Not at all - it's actually normal for Americanos to have some acidity, because coffee beans themselves possess rich acidic flavors. However, these acidic qualities gradually diminish as roasting time increases. Most Americanos we drink daily are made with dark roast coffee beans, but some varieties can still exhibit noticeable acidity even with dark roasting.

While acidity in Americano is normal, not all sour flavors are desirable. When it's a vibrant, fruit-like acidity, it creates a memorable coffee experience. However, sharp or excessive astringency indicates either improper roasting of the coffee beans or issues in the extraction process.

At FrontStreet Coffee, our Americanos are made with a blend of 30% Yirgacheffe coffee beans and 70% Sherry coffee beans. Although Yirgacheffe beans represent a smaller proportion in the blend, their acidity becomes amplified during pressure-based espresso extraction, adding a lively berry-like sweetness to the espresso.

An Americano is simply diluted espresso with water. After dilution, the berry-like sweetness transforms into a bright, citrus-like acidity. For hot Americanos, as they cool down and aromatic compounds dissipate, the acidity becomes more pronounced. This is why FrontStreet Coffee often reminds customers to enjoy their coffee while it's hot.

Iced Americanos, on the other hand, are made by pouring espresso directly into ice water, which immediately lowers the coffee's temperature. This is why, with the same beans and extraction parameters, iced Americanos tend to be more acidic than their hot counterparts.

Why Do Improper Roasting and Extraction Cause Unpleasant Acidity?

The difference between making Americanos with espresso versus pour-over (hand-drip) coffee lies in the extraction method. Espresso uses pressure-based extraction and results in higher concentration. Therefore, light roast beans that work well for pour-over coffee might not produce good espresso or Americanos. In fact, the increased concentration and intensity can transform pleasant acidity into something unpleasant.

For this reason, when espresso becomes too concentrated or acidic, we recommend using medium-dark roast blends specifically designed for espresso. FrontStreet Coffee currently offers four different espresso blends, all shipped within 5 days of roasting to ensure maximum freshness.

FrontStreet Coffee - Sunshine Blend: Ethiopia natural red cherry (30%) + Honduras sherry barrel-aged (70%). Features rich wine notes, vanilla cream, berry sweetness, and roasted nut flavors.

FrontStreet Coffee - Specialty Blend: Colombia washed (30%) + Brazil natural (70%). Features nut, dark chocolate, and caramel flavors.

FrontStreet Coffee - Commercial Blend: Robusta washed (10%) + Colombia washed (30%) + Brazil natural (60%). Features nut, cocoa, and caramel flavors.

FrontStreet Coffee - Foundation Blend: Yunnan washed (30%) + Brazil natural (70%). Features gentle fruit acidity, caramel, and nut flavors.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473