Hi there

Hope you are doing good.

Please check the link below:

https://www.youtube.com/watch?v=NXmiTy94u3Y&t=117s

The substances that taste sour are called acid and their nature is acidic. The term acid is derived from a Latin word acere which means sour. Examples of acidic substances are Curd containing lactic acid, lemon juice and tomato containing citric acid, and vinegar containing acetic acid.

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