Isomalt

• BPIsomalt
• Ph. Eur.Isomalt
• USP–NFIsomalt

galenIQ; hydrogenated isomaltulose; hydrogenated palatinose; Isomaltidex; Palatinit; E953

Mixture of 6-O-α-D-glucopyranosyl-D-glucitol (1,6-GPS) and 1-O-α-D-glucopyranosyl-D-mannitol dihydrate (1,1-GPM) · [64519-82-0]

C12H24O11 (1,6-GPS); C12H24O11·2H2O (1,1-GPM) · 344.31 (1,6-GPS); 380.32 (1,1-GPM dihydrate)

Diluent (filler), Sweetening agent

Typical concentrations: — · Dosage forms: Solid

A sugar-free bulk sweetener used as a filler-binder in tablets (particularly direct-compression, chewable and effervescent tablets), in lozenges and hard-boiled medicated sweets, in sugar-free coatings and as a sweetener in powders and syrups. Agglomerated grades are designed for direct compression. It is widely used in confectionery.

A white or almost white, odourless, crystalline powder or granules with a sweet taste, about half as sweet as sucrose. Commercial grades differ in the GPS:GPM ratio and in particle size.

Sweetness

about 0.45–0.6 times that of sucrose

Melting range

about 145–150 °C

Water content

≤ 7% w/w (mainly water of crystallisation of GPM)

Hygroscopicity

low; takes up little moisture below about 85% RH at 25 °C

Solubility

freely soluble in water (about 25 g/100 g water at 20 °C, rising steeply with temperature); practically insoluble in ethanol

Chemically very stable; it is resistant to acid and enzymatic hydrolysis and, being non-reducing, does not brown. It withstands the high temperatures used in hard-candy manufacture. Store in a well-closed container in a dry place.

No significant incompatibilities are known. As a non-reducing polyol it does not take part in Maillard reactions with amine drugs.

Made in two steps: sucrose is enzymatically rearranged to isomaltulose (palatinose), which is then catalytically hydrogenated to give the mixture of GPS and GPM. The product is crystallised, dried and milled or agglomerated.

Non-cariogenic and only partly absorbed, so it has a low glycaemic response and lower energy value than sugar, making it suitable for diabetic patients. Like other polyols, large amounts can cause flatulence and laxative effects.

Observe normal precautions for the quantity handled; eye protection and a dust mask are recommended.

GRAS listed. Accepted as a food additive in Europe (E953); foods containing more than 10% added polyols must carry a warning that excessive consumption may have laxative effects. Included in the FDA Inactive Ingredient Database (oral preparations) and in non-parenteral medicines licensed in Europe.

Lactitol; maltitol; mannitol; sorbitol; xylitol.

Its low hygroscopicity is an advantage over sorbitol and maltitol in lozenges and chewable tablets, which stay less sticky in humid climates. Isomalt can also be melted and cast or extruded to make medicated lozenges or solid dispersions.