Sourness
Any flavor or gustatory perception that could be roughly described as acidic or caustic is called a sour taste sensation. We use words like soapy, tart, corrosive, sharp, astringent, tangy, acerbic, rancid, vitriolic, biting, vinegary etc. to identify these flavors. To make a binary description of a sour sensation compare it to tasting a lemon. Report the result using one of the following algebraic statements. If the two experiences are not comparable, then say that the sensation is not a sour sensation and express this as $\delta_{\sf{H}}=0$. If the sensation is like tasting a lemon, then say that it is tart. Write this as $\delta_{\sf{H}}=+1$. If the sensation is not like tasting a lemon, then say that it is soapy and that $\delta_{\sf{H}}=-1$. The number $\delta_{\sf{H}}$ is called the sourness.

 Summary
 Adjective Definition Sourness $\delta_{\sf{H}} \equiv \begin{cases} +1 &\sf{\text{if a sour taste sensation is tart }} \\ \ \ 0 &\sf{\text{if a sensation is not sour }} \\ -1 &\sf{\text{if a sour taste sensation is soapy }} \end{cases}$ 2-8
page revision: 56, last edited: 04 Sep 2019 21:43