To make sour.
Too much lemon juice will sour the recipe.
To become sour.
To spoil or mar; to make disenchanted.
To become disenchanted.
We broke up after our relationship soured.
To make (soil) cold and unproductive.
To macerate (lime) and render it fit for plaster or mortar.
To process (fabric) after bleaching, using hydrochloric acid or sulphuric acid to wash out the lime.
That has become or been made sour.