Several different chemicals are used as artificial sweeteners.
The very first was sugar of lead, used by the Romans. It was made by boiling grape juice in lead pots, but it’s quite toxic and was banned in the 18th century (indeed, Beethoven may have died from it).
Modern sweeteners, meanwhile, are made in complex chemical reactions with lots of separate steps and there may be several different processes used for each one, to get around patents.
Saccharine manufacture begins by reacting anthranilic acid with nitrous acid. Sucralose (marketed as Splenda) substitutes three of the hydroxide groups on an ordinary sugar (sucrose) molecule with chlorine atoms. Aspartame is made from two natural amino acids that are joined together and methylated, while stevia (PureVia and Truvia) is derived from the leaves of a South American shrub.
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