What Was I?

Photo by jo-h CC BY 2.0












Remember these? Or if you’re unfamiliar with the ‘flying saucers’ (hence a clue on Twitter: Fox Mulder’s favourite sweeties), they are essentially sherbet wrapped up in coloured rice paper (starch really). Sweeties is really a misnomer – in many cases the joy of sweets is the sourness, often caused by tartaric, citric or malic acid, and a fizz caused by a reaction between the acid, water (such as saliva or water if sherbet drink crystals), and some source of carbon dioxide such as a sodium bicarbonate.  The carbon dioxide is produced in the reaction, giving that glorious bubbly sensation on your tongue.   In the case of the ‘What Am I?’ below, tartaric acid and sodium bicarbonate and a bit of sucrose were wrapped up in a starchy wrapper of various colours.

Sherbet comes in a variety of forms – soda crystals such as Creamola Foam (sadly no longer made under that name), the sherbet dib dab (a lolly for sticking into sherbet powder, Dumbledore’s favourite sherbet lemons (although I prefer the strawberry ones) and the sherbet fountain which I always found wonderful but for the vile licorice that came with it.

I have to go now and teach some acid-base chemistry to some first year students, but perhaps I’ll see if any of them know of  a common acid base reaction that goes on in their mouths when they eat sherbet sweeties…