All About Sweeteners
by D. Eric Walters, Ph.D.

Artice of the week:

Sweetener article of the week

Tagatose

     

Other names:
NaturloseĀ™

Taste:
Tagatose has a clean sweet taste.  It is about 90% as sweet as sucrose on a weight basis.

Calories:
Tagatose, like the polyols, is only partly absorbed by the body, and not converted to energy very efficiently.  Its caloric value depends on several factors, as discussed in my essay "Polyols and Calories."  In the USA, tagatose provides 1.5 calories per gram for labeling purposes.  In the European Union, it is listed at 2.4 calories per gram.

Safety:
Tagatose occurs naturally (at low levels) in some yogurts, since it is a metabolic intermediate of lactobacilli.  It has GRAS status in the USA.  The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has approved tagatose as a "novel food ingredient", with no limitation on its usage. Unabsorbed tagatose can cause some digestive system unhappiness, including gas, rumbling sounds (borborygmas), and diarrhea.  You can read about this in my recent essay, "Polyols--Digestive Issues."
     The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has determined the "Laxative Threshold Value" (LTV) for a number of polyols and low-digestible sugars.  Tagatose is one of the less laxative polyols, with an LTV of 40 grams per meal. 

Chemistry:

Molecular formula: C6H12O6

Molecular weight: 180.16

     Tagatose is chemically very similar to fructose--it differs only with respect to the stereochemistry at the C4 carbon.

chemical structure tagatose

Properties:
Tagatose solubility in water is 58%.  It is less hygroscopic (absorbing moisture from the air) than fructose.  Unlike the polyols, tagatose can participate in browning reactions--this is an important quality in baking applications.

Other links:
Tagatose on Wikipedia

SweetenerBook.com

This site is changing daily!  Most recently updated 26 June 2008.  All material is © copyrighted property of Walters Associates.  All rights reserved.

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