Lemon syrup has been used as a flavouring for centuries and was especially popular during the heyday of the American soda fountain in the mid 1800s. Early newspaper articles suggest that lemon soda, made with lemon syrup and soda water, may have been the first flavoured soda. Lemon soda was most certainly the most popular flavour in 1840 and remained king of the soda fountain for at least another 30 to 40 years.
The original lemon syrup was made using lemon oil, sugar, water and an acid. Many of the original syrup recipes were made using the oils from the fruit because it was the best way to preserve the fruits flavours. If fresh lemons were available, the lemon juice would be used to acidify the soda, however, in many northern states, lemons were only available seasonally so alternative acids were used. Some of these acids included citric and tartaric acid, but both presented problems, especially citric acid as the method of production contaminated it with lead. Acid Phosphate and lactic acid were also used, with Acid Phosphate becoming the dominant acidulant from the 1870s until 1914.
Organoleptics: lemon, sweet, citrus