What would life be like if nothing was sweet?
There are many sweeteners in use today. Some are nutritive sweeteners like sugar, others are non-nutritive like saccharine, and still others sit on the border, with fewer calories than sugar, or poorly metabolized in the body, or both.
Here is a list of sweeteners sorted according to how sweet they taste:
|high fructose corn syrup||120|
|sucrose (table sugar)||100|
|regular corn syrup||40|
The non-nutritive sweeteners stand out in the table because they are so much sweeter than sugar.
Sugar is a disaccharide, two simple sugars in one molecule. The two simple sugars are glucose and fructose.
Glucose is not as sweet as sugar, but fructose is much sweeter. This is why high fructose corn syrup is sweeter than sugar, and why breaking the sugars in sucrose apart into glucose and fructose (making invert sugar) results in a sweeter mixture.
Adding a hydrogen or two to a sugar makes a sugar alcohol. The sugar alcohols xylitol, maltitol, sorbitol, and mannitol are all used as sweeteners in food. They are not absorbed by the body well, and they don't have as many calories. As with any food that is not absorbed well, too much can have laxative effects.
Sugar alcohols are found in many foods naturally, and are created by the body as a normal part of metabolism. They are similar to sugar in their properties, and so they can be used like sugar in cooking. Variations in their hygroscopicity (absorbing water from the air), their melting points, and their reactions with other ingredients determine which are used in a particular recipe.
Sugar alcohols do not brown like sugar, and so they are used when carmelized brown color is not desired.