
Bitter lemon is a carbonated soft drink bittered by lemon pith and quinine and soured by lemon juice.
Bitterness leads — the astringent quinine-and-pith edge — layered over a sour lemon body, a balancing sweetness, and citrus-peel fragrance on the nose.
Reached for when a tall drink needs both quinine bitterness and a sour-citrus lift in one lengthener, it is built over ice and topped to fill. Because it arrives pre-sweetened and acidic, it shifts a drink's balance more than plain soda water, so the rest of the build is adjusted around its sugar and sourness.
Hard to swap cleanly, since it supplies volume, carbonation, sour citrus and quinine bitterness at once; the nearest approximation is tonic water with fresh lemon juice, adjusting sweetness with simple syrup, as no non-quinine soda can reconstruct the bitterness.
Bitter lemon is a quinine drink that additionally contains lemon juice, pith and peel, giving it a sourness and citrus-peel fragrance that plain tonic water lacks.
This sparkling soft drink combines the quinine bittering common to tonic water with added lemon juice, pith and peel; the juice brings sourness offset by extra sweetener, while the oily peel contributes fragrance. Its signature bitterness derives from inherently bitter lemon pith reinforced by the alkaloid quinine.
The generic bitter lemon drink dates to 1834, with a branded version introduced in 1957.