by Darcy O'Neil on December 2009
Soda phosphates are a class of drink the has disappeared from the beverage world. Yes, many places claim to sell “phosphates” but they really aren’t the original article. To be considered a true phosphate the drink must include “acid phosphate” and not citric acid or lemon juice. The problem is acid phosphate stopped being produced decades ago. But, when I was researching Fix the Pumps, I discovered the recipe for this long lost acidulent. With a freshly made bottle of acid phosphate in hand, the once supremely popular Wild Cherry Phosphate was a drink I needed to try.
The Cherry Phosphate and the Wild Cherry Phosphate were two drinks that were found at every soda fountain. The regular version uses cherry juice and sugar as the key flavour components and the wild version uses wild cherry bark for the flavour.
Wild cherry bark is widely available through herb companies and is sourced from the Choke Cherry tree. Like apricot kernels and bitter almonds, wild cherry bark contains amygdalin (laetrile, nitriloside) which, in the presence of water, hydrolyzes to form hydrogen cyanide, benzaldehyde or acetone. Cherry bark produces about 0.4% by weight of amygdalin, whereas apricot kernels can have up to 3%.
Extracting the components of wild cherry bark can be done a couple of ways, but the method I’ve selected uses water and glycerol (4:1) as the solvent. Boiling water can be used but the high temperature breaks down some of the unique flavour components. Dilute alcohol can be used as a solvent, but this increases the levels of prussic acid (hydrogen cyanide) in the extract. According to old pharmacy manuals, the use of glycerin is said to check the production of the prussic acid making it a better choice for beverage purposes. This is unconfirmed in modern literature.
The fact remains that wild cherry bark has been used for centuries as an effective cough syrup and bitter tonic for appetite and digestion. Many herbal remedy site recommend making a cough syrup by filling a glass jar one-third full with wild cherry bark and then filling with Southern Comfort (!). I don’t recommend that.
The recipe included here uses a combination of cherry juice and 1 oz of the bark for 20 oz of syrup. This means the amount of hydrogen cyanide produced is very small. Historical recipes call for twice as much bark, or more. This method gives the unique flavour of the bark while keeping any concerns about cyanide to a minimum.
Wild Cherry Syrup
1 oz (30 ml) Cherry Bark
4 oz (60 ml) Cherry Juice
1 oz (30 ml) Glycerin
4 oz (120 ml) Water
10 oz (300 ml) Sugar
Water to make 12 oz (360ml)
Mix the glycerin with 4 oz of water, add to the bark and macerate for 24 hours. Filter the liquids off the bark and then 4 oz of warm water and macerate for another hour. Filter and add this extract to the first one. Add the cherry juice and if needed water to make 12 oz of liquid. To the liquid dissolve the sugar without any heat.
Wild Cherry Phosphate
1½ oz Wild Cherry Syrup
1 tsp Acid Phosphate
In a 10 oz glass add the wild cherry syrup and the acid phosphate. Fill the glass with ice cold soda water and mix with a spoon if necessary.
This Wild Cherry Phosphate tastes amazingly good. It has the flavour of almonds and cherry, but a very natural taste and not even remotely close to the artificial cherry cough syrup flavour.
Once you’ve tried a Wild Cherry Phosphate it becomes obvious why this drink was popular for decades. But everything great must have some downside. There’s that hydrogen cyanide thing, which isn’t a big deal but some people are easily frightened. I still wouldn’t recommend going on a bender though, but hey look I'm still writing. Secondly, wild cherry bark makes a great tonic for the stomach but it can also make some people drowsy, which isn’t necessarily great for a bar. Unless of course you have an annoying customer who needs to be sedated.
From time-to-time I must tap my inner car salesman to let you know that buying Fix the Pumps is a great way to support Art of Drink. If you've enjoy reading this post and the other articles here, then the book is like a 180 page post, not including cover, TOC, index, etc. Also, if you’ve ever thought “that was a good post, if I ever meet Darcy I’ll buy him a drink” I’ll happily accept book sales in lieu of a drink. OK, enough of the inner car salesmen for now, but really, Fix the Pumps is full of great content and contains a full dissertation on acid phosphate and other unique ingredients used at soda fountains that could easily be used behind the bar.