Sucrose

What is Sucrose?

Sucrose, or table sugar, organic compound, sweet - tasting colorless crystals that dissolve in water. Sucrose is a disaccharide that produces "invert sugar" or “inverted sucrose” by the enzyme invertase on hydrolysis. (So, named because the hydrolysis results in an inversion of rotation of the polarized plane light).

Sucrose is naturally found in sugarcane, sugar beets, maple sap, dates, and honey. It is commercially produced in large quantities (especially from sugar cane and sugar beets) and is almost entirely used as food.

Sucrose Examples: Primarily sucrose is present in bananas, sweet peas and peaches. Sugar cane and sugar beets store the greatest quantities of sucrose and are thus harvested as commercial sugar sources.


Sucrose Meaning:

A light crystalline non - reducing dextrorotatory disaccharide sugar that occurs naturally in most plants and is obtained commercially from sugar cane or sugar beets.

Sucrose Chemical Formula: C12H22O11

IUPAC Name: β-D-Fructofuranosyl α-D-glucopyranoside

Synonyms: 

  • Sugar

  • Saccharose

  • α-D-glucopyranosyl-(1→2)-β-D-fructofuranoside

  • β-D-fructofuranosyl-(2→1)-α-D-glucopyranoside


Composition:

The sucrose is composed of one glucose molecule connected to one fructose molecule by means of a glycosidic bond. The two constituent monosaccharides are present in 1:1 ratio.


Structure of Sucrose:

One of the common disaccharides is sucrose that gives an equimolar combination of D-(+)-glucose and D-(-) fructose on hydrolysis.

These two monosaccharides are held together by a glycosidic interconnection between α-D-glucose C1 and β - D-fructose C2. Since the reduction groups of glucose and fructose are involved in the formation of glycosidic bonds, sucrose is a non-reductional sugar.

Cyclic structure of sucrose shows that α D-glucopyranose and β D-fructofuranose rings are linked by glycosidic linkage.

Sucrose is dextrorotatory but yields dextrorotatory glucose and laevorotatory fructose after hydrolysis. Because fructose levorotatory(– 92.4°) is greater than glucose dextrorotation (+52.5 °), the mixture is laevorotatory. Thus, sucrose undergoes hydrolysis, it  leads to a change in the sign of rotation (from dextro (+) to laevo(–) ) and the resultant product is called invert sugar.

Various Structure Models of Sucrose:

Sucrose Chemical Structure

(image will be uploaded soon)


Ring - Structure of Sucrose 

(image will be uploaded soon)


Haworth Structure of Sucrose

(image will be uploaded soon)


Sucrose Molecular Structure

(image will be uploaded soon)


Properties of Sucrose:

Physical Properties:

  • The sucrose C12H22O11 molar mass is 342.30 g/mol.

  • It appears as white crystal solid.

  • It has a density of 1.587 g/cm3.

  • Its melting point: None; decomposes at 186 °C (367 °F; 459 K).

  • Solubility: it is soluble in water.


Chemical Properties

If sucrose passes through acid catalyzed hydrolysis, one D-Glucose mole and one D-Fructose mole will be produced.

The chemical structure of sucrose consists of α form glucose and β form fructose

The glycosidic connection is α connection, because the formation of the molecule is in α orientation

The structure of the hemiacetal oxygen is mixed (linked) and does not have a free hemiacetal hydroxide.Since there is no free hemiacetal hydroxide, the mutarotation (α to β conversion) does not show. Sucrose doesn't also form osazones for the same reason.

The structural formula of sucrose can be confirmed by hydrolysing it with enzymes of α-glycosidase that hydrolyze only α glucose. 

Sucrose crystallizes with room temperature (lattice parameters a = 1.08631 nm, b = 0.87044 nm, c = 0.77624 nm, β = 102.938 °), in the monoclinic space group P21.

Polarimetry determines the purity of sucrose, through the rotation of plane-polarized light by a sugar solution. Using yellow "sodium-D" light (589 nm) the specific rotation at 20 ° C is + 66.47°.


Uses of Sucrose:

  • Sucrose in plants is consumed by many mammals, birds, insects and bacteria

  • Sucrose is a key component of soft drinks and other beverages.

  • This compound is used in many of the medicines.

  • To many emulsifying agents and detergents, it acts as a chemical intermediate.

  • It also acts as an agent for food thickening and as a nutrient stabiliser.

  • With the aid of this compound the shelf life of many food products, such as jams and jellies, is prolonged.

  • Using sucrose in baking results in the baked products being brown in colour.

  • This compound also serves as an   antioxidant   (a compound that inhibits oxidation).

  • Sucrose is widely used as a preservative in foods.


Key Points:

Sucrose, or table sugar with a chemical formula of C12H22O11, is a common type of sugar made of glucose and fructose. It is a disaccharide, meaning that it is made up of two monosaccharide sugar units and a simple carbohydrate.

Sucrose is a disaccharide that produces "invert sugar" or “inverted sucrose” by the enzyme invertase on hydrolysis.

These two monosaccharides are held together by a glycosidic interconnection between α-D-glucose C1 and β - D-fructose C2. Since the reduction groups of glucose and fructose are involved in the formation of glycosidic bonds, sucrose is a non-reductional sugar.

FAQ (Frequently Asked Questions)

Is Sucrose the Same as Sugar?

Sucrose is the name for table sugar in scientific terms. The sugar is classified as monosaccharides or disaccharides. Table sugar is commonly extracted from sugar cane or sugar beets and the sucrose found in processed foods. Sucrose has a stronger flavor than fructose but is sweeter than glucose.

What is Sucrose Made of?

Sucrose is made up of glucose and fructose units:

Sucrose or table sugar is made from cane sugar or beet sugar. The glucose and fructose groups are joined by an acetal oxygen bridge on the glucose in α -1 and the fructose in β -2.

What Color is Sucrose Sugar?

Sucrose sugar is white in color, where it is prepared from yellowish raw sugar.