sour v. bitter

Sour foods are acidic, and include certain fruits (e.g., lemons, oranges, and grapes), and some fermented foods, like wine and yogurt.

Various chemicals are perceived as tasting bitter. Bitter foods include some vegetables, (e.g., endives, spinach, and cabbage), and also cocoa, coffee, tea, beer, and tonic water. Bitter compounds are often toxic, so people are especially sensitive to bitter flavors.

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