acids
Some foods that are sour are lemons, grapes, and tamarind. Some types of oranges and some melon can also have a sour taste to them.
Lemonade or vinegar are examples of foods that have a sour taste.
damaged taste buds, severe head trauma, brain damage or a birth defect.
I have never noticed a sour taste in my dairy foods. You are possibly letting it get over date.
Lactic acid produced by fermentation.
Sour tasting foods are usually acidic. The sour taste in foods comes from acids such as citric acid, malic acid, or acetic acid that stimulate taste receptors on our tongue and trigger a sour sensation.
Acids typically have a sour taste. Examples of acidic foods include lemons, vinegar, and sour candies.
When you taste sour while consuming certain foods or beverages, it is because they contain acids that stimulate taste receptors on your tongue, sending signals to your brain that interpret the sensation as sour.
Miracle fruit is a taste-altering berry that contains a protein called miraculin. When eaten, miraculin binds to taste receptors on the tongue and tricks the brain into perceiving sour foods as sweet.
Probably , sour .
Lime
The presence of acidic compounds in a solution is what causes it to taste sour. These compounds release hydrogen ions when dissolved in water, stimulating sour taste receptors on the tongue. Examples of acidic compounds that contribute to a sour taste include citric acid in citrus fruits and acetic acid in vinegar.