Sugar alcohol

Particular feedstocks are starch, cellulose and hemicellulose; the main conversion technologies use H2 as the reagent: hydrogenolysis, i.e. the cleavage of C−O single bonds, converting polymers to smaller molecules, and hydrogenation of C=O double bonds, converting sugars to sugar alcohols.

This table presents the relative sweetness and food energy of the most widely used sugar alcohols.

In addition to their sweetness, some sugar alcohols can produce a noticeable cooling sensation in the mouth when highly concentrated, for instance in sugar-free hard candy or chewing gum.

The cooling sensation is due to the dissolution of the sugar alcohol being an endothermic (heat-absorbing) reaction,[1] one with a strong heat of solution.

As an exception, erythritol is actually absorbed in the small intestine and excreted unchanged through urine, so it contributes no calories even though it is rather sweet.

[1][14] Like many other incompletely digestible substances, overconsumption of sugar alcohols can lead to bloating, diarrhea and flatulence because they are not fully absorbed in the small intestine.

With continued use, most people develop a degree of tolerance to sugar alcohols and no longer experience these symptoms.