Main Difference – Maltose vs Sucrose
Carbohydrate, which is an essential macromolecule to all living creatures in the world, can be divided into three categories known as monosaccharides, disaccharides, and polysaccharides. Maltose and sucrose are considered as simple and most abundant disaccharides in the world. However, there seems to be a lot of confusion over the difference between maltose and sucrose because they have a similar formula (C12H22O11) and similar molar mass (342.30 g/mol). Both maltose and sucrose are created when two simple sugars combine. The key difference between maltose and sucrose is that maltose is a combination of two molecules of glucose whereas sucrose is a combination of glucose and fructose. In addition, maltose is a reducing sugar while sucrose is a non-reducing sugar.
This article describes,
1. What is Maltose? – Definition, Structure, Synthesis, and Properties
2. What is Sucrose? – Definition, Structure, Synthesis, and Properties
3. What is the difference between Maltose and Sucrose
What is Maltose
Maltose is a disaccharide sugar, and its monomer unit is glucose. It is also known as maltobiose or malt sugar. To synthesize a maltose molecule, two molecules of glucose are joined with an α (1→4) glycosidic bond as a result of a condensation reaction. Starch is broken down into maltose in the presence of amylase enzyme. Maltose is produced in seed germination and glucose caramelization process.
Maltose syrup
What is Sucrose
Sucrose is a non-reducing sugar and is also known as Saccharose because it is mainly found in many plants. Its molecular formula is C12H22O11. It can be isolated from cane or beet sugar and used for human consumption. Sucrose is mainly important for beverage industries and bakery products because it contributes to enhancing the taste and palatability, and color development. However, excess consumption of sucrose is directly linked to health conditions such as tooth decay, glycemic index and rapid increase in blood glucose levels that leads to diabetes mellitus and obesity.
Granulated Sugar
Difference Between Maltose and Sucrose
History
Maltose was first introduced by Irish chemist and brewer Cornelius O’Sullivan in 1872.
Sucrose was first described by the English chemist William Miller in 1857.
Natural Sources
Maltose is naturally found in beer, cereal such as barley and wheat, pasta, soybeans, potatoes and sweet potatoes.
Sucrose is stored in plants because it is less reactive. It is naturally present in cane or beet sugar, and they are used for table sugar extraction. In 2013, average sucrose production was 175 million metric tons worldwide.
Alternative Names
Maltose is also known as 4-O-α-D-Glucopyranosyl-D-glucose, maltobiose and malt sugar.
Sucrose is also known as sugar, Saccharose, α-D-glucopyranosyl-(1→2)-β-D-fructofuranoside, dodecacarbon monodecahydrate,β-D-fructofuranosyl-(2→1)-α-D-glucopyranoside,β-(2S,3S,4S,5R)-fructofuranosyl-α-(1R,2R,3S,4S,5R)-glucopyranoside, α-(1R,2R,3S,4S,5R)-glucopyranosyl-β-(2S,3S,4S,5R)-fructofuranoside
Monomer Units
Maltose is a disaccharide formed from two units of glucose.
Sucrose is a disaccharide formed from glucose unit and fructose unit.
IUPAC Name
Maltose’s IUPAC name is 2-(hydroxymethyl)-6-[4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyox ane-3,4,5-triol.
Sucrose’s IUPAC name is (2R,3R,4S,5S,6R)-2-[(2S,3S,4S,5R)-3,4-dihydroxy-2,5-bis(hydroxymethyl)oxolan-2-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol.
Molecular Structure
Sucrose is a disaccharide combination of monosaccharides glucose and fructose, joined with an α(1→4) bond, formed from a condensation reaction. Its chemical formula is C12H22O11. On the other hand, hydrolysis breaks the glycosidic bond converting sucrose into glucose and fructose.
Molecular formula of Sucrose
Maltose is a disaccharide combination of the two molecules of monosaccharides glucose joined with an α(1→4) bond, formed from a condensation reaction. Its chemical formula is C12H22O11. On the other hand, hydrolysis breaks the glycosidic bond converting maltose into glucose.
Molecular formula of Maltose
Chiral Rotation
Maltose’s purity can be measured by polarimetry. The rotation of plane-polarized light by a solution of maltose is +140.7°.
Sucrose’s purity can be measured by polarimetry. The rotation of plane-polarized light by a solution of sucrose is +66.47°.
Biochemical Synthesis Process
Maltose is synthesized in
- Seed germination process
- Caramelization reaction
- Starch breakdown by the action of amylase during oral digestion and pancreatic digestion
Sucrose is synthesized in the beet sugar and cane during the photosynthesis process.
Reducing Properties
Maltose is a reducing sugar, and it has free aldehyde group. Thus it can reduce Fehling’s reagent.
Sucrose is a non-reducing sugar because it does not have any anomeric hydroxyl groups. Thus, it can’t reduce Fehling’s reagent.
Osazone Crystal Formation
Maltose form petal-shaped crystals. Osazone test can be used to identify maltose from other sugars.
Sucrose is a non-reducing sugar, and it does not form Osazone crystals.
In conclusion, maltose and sucrose are primarily sugars and chemically they are categorized as disaccharides are which used as a sweetening agent. Sucrose is a highly available food ingredient compared to maltose. However, there is a controversial issue about the safety of the long-term consumption of these natural sugars.
References:
Weast, Robert C., ed. (1981). CRC Handbook of Chemistry and Physics (62nd ed.). Boca Raton, FL: CRC Press. p. C-367.
Lombardo, Y. B., Drago, S., Chicco, A., Fainstein-Day, P., Gutman, R., Gagliardino, J. J., Gomez Dumm, C. L. (1996). Long-term administration of a sucrose-rich diet to normal rats: relationship between metabolic and hormonal profiles and morphological changes in the endocrine pancreas. Metabolism. 45 (12): 1527–32.
Mintz, Sidney (1986). Sweetness and Power: The Place of Sugar in Modern History. Penguin. ISBN 978-0-14-009233-2.
Image Courtesy:
“Saccharose2” By NEUROtiker – Own work (Public Domain) via Commons Wikimedia
“Maltose2” By NEUROtiker – Own work (Public Domain) via Commons Wikimedia
“Sugar 2xmacro” By Lauri Andler(Phantom) – Own work (CC BY-SA 3.0) via Commons Wikimedia
“Maltose syrup” By www.aziatische-ingredienten.nl (CC BY-SA 2.0) via Commons Wikimedia
