No, a bitter beer is not a sour.
While both bitterness and sourness are distinct taste profiles found in various foods and beverages, including beer, they are caused by different compounds and are perceived differently by the palate. The provided reference clearly highlights this distinction:
First of all, we need to differentiate two often confused, but quite different, tastes. Sourness is caused by acidity – think lemons, with their citric acid. Bitterness is more of an earthy, sharp taste, as you might find in coffee, strong chocolate or cranberries.
Understanding the Difference
Based on the reference and general sensory science, we can outline the key differences:
-
Sourness:
- Cause: Primarily caused by the presence of acids, such as citric acid (lemons), lactic acid (yogurt, some beers), or acetic acid (vinegar).
- Perception: Often described as tart, tangy, or acidic. It typically causes a puckering sensation in the mouth.
- Examples: Lemons, vinegar, sour candy, some types of yogurt, and intentionally brewed sour beers.
-
Bitterness:
- Cause: Often caused by compounds like alkaloids (coffee, quinine), polyphenols (dark chocolate, tea), or hop compounds (in most beers).
- Perception: Described as an earthy, sharp, or sometimes acrid taste. It is typically perceived at the back of the tongue.
- Examples: Coffee, dark chocolate, cranberries, tonic water, and hop-forward beers like IPAs.
Sour vs. Bitter: A Quick Comparison
Here is a simple table summarizing the main points:
| Feature | Sourness | Bitterness |
|---|---|---|
| Primary Cause | Acids (Citric, Lactic, etc.) | Various compounds (Hops, Alkaloids, etc.) |
| Taste Description | Tart, Tangy, Acidic, Puckering | Earthy, Sharp, Sometimes Acrid |
| Typical Examples | Lemons, Yogurt, Sour Candy | Coffee, Dark Chocolate, Hops |
Beer Styles & Taste
Many popular beer styles are known for their bitterness, which primarily comes from hops. Examples include:
- India Pale Ales (IPAs): Characterized by significant hop presence, leading to high bitterness.
- Pale Ales: Also hop-forward, though generally less bitter than IPAs.
- Stouts: Can have bitterness from roasted malts as well as hops.
On the other hand, "sour beers" are a specific category brewed using wild yeast (like Brettanomyces) or bacteria (like Lactobacillus or Pediococcus) which produce lactic or acetic acid, resulting in an intentionally sour taste. Examples of sour beer styles include:
- Lambics
- Gueuze
- Flanders Red Ale
- Gose
Therefore, while a beer can possess both bitter and sour notes, a beer primarily described as "bitter" is distinct from one categorized as "sour." The dominant taste sensation and its source define whether a beer is called bitter or sour.
