Artificial sweetener molecules - rotatable in 3 dimensions

Since sucrose and other sweet-tasting carbohydrates can be metabolised to give energy, they are avoided by some consumers who are "counting the calories". They are also liable to cause tooth decay. Alternative compounds have therefore been developed. Sometimes these are classed as 'flavour enhancers'.
Artificial sweeteners are also important in the dietary requirements of sufferers from diabetes and obesity who must limit their carbohydrate intake.
To some there is great public demand and hence marketing potential for these products; others view them with concern from a number of angles.
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is a dipeptide, composed of 2 amino acids ( aspartic acid and phenylalanine), with a methyl group , so it is a methyl ester.

It is said to be 180 times as sweet as sugar (sucrose), and it contains only about 4% of the calories of the equivalent amount of sugar.

It is damaged by heating, so its main use is in fizzy drinks. Nutra-sweet is a common brand.

On digestion it is converted into phenylalanine and aspartic acid and methanol.
Drinks and other products containing aspartame must carry a warning "contains a source of phenylalanine" so that sufferers from phenylketonuria can avoid them.
Aspartame is distrusted by some, and spoof articles criticising it abound online, most citing the same false sources. .
Some also call into question the reputation of the developers the NutraSweet Company, once owned by GD Searle - then a Monsanto company - as well as the U.S. Food & Drug Administration.
And of course there are suspicions that manufacturers of standard carbohydrate-based sweeteners have an axe to grind.
Neotame has also become included in this misinformation campaign.


is a development from aspartame.
The only real difference is that a 3,3-dimethylbutyl group has been attached to the amino group of the aspartic acid which is still bonded by a peptide bond to phenylalanine, which itself has a methyl group attached to its COOH group.

The 3,3-dimethylbutyl group protects the peptide bond from being hydrolysed, so that phenylalanine is not released, but esterase enzymes can still de-esterify the molecule releasing (a small amount of) methanol.

Neotame is said to be 8000 (or more) x sweeter than sugar. Consequently
- much less is required
- there are practically no issues regarding breakdown products
- it may not need to be put on the list of ingredients (?)

It is more thermally stable than aspartame.

Acesulfame K

is the potassium salt of 6-methyl-1,2,3- oxathiazine-4(3H)-one 2,2-dioxide.
It is about as sweet as aspartame. It may have a slight aftertaste, so it is often mixed with it or other sweeteners, for example in Canderel products.
As it is unaffected by high temperature, it can be used in foods to be cooked.
Sucralose is a cross-over product - as it is based on the natural product sucrose, but with chemical modifications


is sucrose which has been modified by the substitution of 3 chlorine atoms (seen here in green) for -OH groups.

It is 600 times sweeter than sucrose, so it is often mixed with other substances to bulk it out. It is marketed under the brand name Splenda.

It is apparently not metabolised or stored in the body like other chlorinated compounds.


(benzoic sulfinide) has been available since the 1880s, although it only became more widely used during wartime sugar shortages.

It is said to be about 300 times as sweet as sucrose, but may display an unpleasant bitter/metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, sweets, medicines, and toothpaste.

For many years fears were expressed about the possibility that it may cause bladder cancer.


Cyclamate is the sodium (or calcium) salt of cyclamic acid (cyclohexanesulfamic acid).

It is said to be 30 to 50 times sweeter than sugar.

In the USA it was approved for use as a table-top sweetener (for diabetics) in 1958 but banned in 1969 after suspicion that it could cause bladder (and other) cancer.

The methodology behind these tests was called into question in 1984 and some of the regulations about its use were lifted. It is currently approved as a sweetener in over 100 countries, though it is still banned in the United States.

Other possibly relevant topics on this website

Stevioside ... Sucrose ... Glucose

Web references

In almost all cases, it is interesting to see how the sweetness of these compounds was originally discovered!
Aspartame From Wikipedia, the free encyclopedia
Aspartame controversy
Aspartame Warning
Neotame From Wikipedia, the free encyclopedia
Neotame - more-toxic than aspartame?
Acesulfame potassium From Wikipedia, the free encyclopedia
Sucralose From Wikipedia, the free encyclopedia
Saccharin From Wikipedia, the free encyclopedia
Sodium cyclamate From Wikipedia, the free encyclopedia
Cyclamate regulatory status
Sweetners - Introduction (sic) is the source of much interesting information about natural and artificial sweeteners, and the background to sweetness in general.