Why Does American Black Coffee Taste Sour When Brewed? Is This Normal? Where Does the Acidity in Single-Origin Black Coffee Come From After Brewing?

Most of the acidity in coffee comes from the coffee beans themselves, though this also relates to personal taste preferences. Generally speaking, coffee from different regions has the following flavor characteristics: African coffees tend to be acidic, South American coffees lean toward nutty and chocolate notes, while Mandheling and Blue Mountain coffees are known for their richness.

Understanding Americano Coffee

In common expression, some people also refer to unsweetened black coffee as Americano. In reality, Americano coffee is simply coffee suited to American tastes. When Americans first encountered espresso, they found the intense flavor difficult to appreciate. American consumers were accustomed to drip coffee, so to achieve a concentration similar to drip coffee, they diluted espresso to a certain extent with water.

To put it simply, Americano is espresso mixed with a certain amount of drinking water. Hot Americano is espresso mixed with hot water, while iced Americano is espresso mixed with ice water.

Is Acidity in Americano Normal?

When coffee wasn't yet widespread in China, only a few large-brand coffee shops and some high-end hotels on the streets could provide coffee. These coffees were predominantly bitter, emitting rich coffee aromas. This shaped an entire generation's impression of coffee. However, with the rise of coffee specialization and Nordic light roasting, fruity sweet and sour flavors emerged from the mainstream style of burnt, bitter, and aromatic coffee. This seed gradually took root and grew, and today there are many shops in the market that specialize in acidic coffees.

Americano coffee with acidity is likely made using SOE as the base. SOE, also known as Single Origin Espresso, generally isn't roasted too deeply to highlight the origin's flavor characteristics, so the resulting espresso having acidity is normal.

Why Does Coffee Have Acidity?

The acidity in coffee beans comes from the beans themselves as well as the roasting process. Good acidity brings richer meaning to the sour taste. Clearly refreshing and pleasant aromas, similar to fruit-like flavors, or soft and rounded acidity sensations all indicate that this is a cup of coffee containing "quality acidity." For example, the citrus acidity in Gesha or the lemon aromatic acidity in washed Yirgacheffe.

On the other hand, poor coffee acidity comes from improper planting, processing, roasting, and brewing, bringing unpleasant acidity sensations, usually accompanied by pungent aromas, creating a "sharp" feeling, which we generally call sourness. Whether coffee will be acidic, whether it's "good" acidity or "bad" acidity, depends on the coffee bean variety, roast degree, and brewing parameters.

How to Avoid Poor Coffee Acidity

Defective Beans

Among defective beans, there are things called full sour/partial sour beans. Beans that appear yellowish-brown or reddish-brown are identified as sour beans, which occurs when the beans ferment and are contaminated by bacteria during harvesting and processing. Therefore, specialty coffee usually selects the highest grade coffee beans, resulting in fewer defects. Of course, FrontStreet Coffee conducts two rounds of manual selection to remove defective beans before and after roasting to ensure coffee quality.

Moreover, FrontStreet Coffee's baristas also carefully remove defective beans during brewing that could affect the coffee's flavor. Through multiple layers of quality control, the coffee's best qualities are expressed.

Roasting

Coffee beans contain acidic organic compounds that can be synthesized by plants themselves and contain weakly acidic aromatic substances with carbon molecules. Organic acids include chlorogenic acid, quinic acid, acetic acid, citric acid, malic acid, lactic acid, etc., and these organic acids will increase or decrease before and after roasting.

If roasting is underdeveloped or dehydration is incomplete, sharp acidity will appear.

Of course, it's also related to the roast degree. The lighter the roast, the lower the degree of caramelization, and at this time, organic acids are still retained in the beans, making it easy to produce acidity. Conversely, the deeper the roast, the less likely there will be acidity, because extended roasting time easily eliminates the floral and fruity aromas in coffee beans.

Brewing

If brewing water temperature is too low or the coffee grounds are too coarse and other factors lead to under-extraction, sharp acidity will also appear. Therefore, to avoid this situation, FrontStreet Coffee needs to repeatedly test brewing parameters to find the appropriate brewing parameters.

The flavors in the coffee world are rich and varied. Isn't the joy of it all being able to taste various different flavors from a single cup of coffee? Fruit acidity is an essential member of this family, because it is these acidity sensations that make the flavor layers of coffee fuller, giving each bean its own personality.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473