Frank J. Wilstach, comp. A Dictionary of Similes. 1916.

Sour

Sour as Melancholy.
—Robert Burton

Sour as verjuice.
—Thomas Dekker

As sour as though he had swallowed
A sloe-bush.
—Maria Lowell

Sour as a rotten orange.
—Justin Huntley McCarthy

Sour as lees in wine.
—Brian Melbancke

Sour as sorrel.
—Thomas Sackville