Difference Between Glucose and Fructose

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Glucose and Fructose are two Simple Sugars. Simple carbohydrates are classified in two ways:

  1. Monosaccharide: A monosaccharide is the most basic form of carbohydrates. The most fundamental source of carbohydrates is a monosaccharide. Within cells, monosaccharides have various roles. Monosaccharides are, first and foremost, used to generate and store energy. Most of the species produce energy by breaking down the monosaccharide glucose and processing the energy released from the bonds. Ex. glucose and Fructose.

  1. Disaccharide: A molecule formed by two monosaccharides, or simple sugars, is a disaccharide, also called a double sugar. Disaccharides are formed by dehydration reactions in which a total of one water molecule is separated from the two monosaccharides. Ex. Sucrose, maltose, and lactose.

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Glucose is a monosaccharide, also known as grape sugar. It is an aldohexose. Glucose is the preferred source of energy for our muscles and brain. 

Preparation of Glucose

1. From Sucrose (cane sugar): By boiling sucrose in an alcoholic solution with dilute HCl and H2SO4, we can obtain glucose and fructose in exactly equal amounts. 

C12H22O11(Sucrose)+ H2O → C6H12O6 (Glucose)+ C6H12O6 (Fructose)

2. From Starch: Glucose can be obtained by the hydrolysis of starch in boiled and dilute H2SO4 at 393 K under pressure.

(C6H10O4)n (Starch or cellulose) + nH2O + H+ → nC6H12O6 (Glucose)

Uses of Glucose

  1. It is provided to patients who are extremely ill and unable to feed because it offers calories from carbohydrates

  2. It is used in the treatment of low blood sugar. 

  3. It is used for the synthesis of matter as a precursor.


Fructose is naturally found in fruits and vegetables, primarily metabolized in our livers.  Via glycolysis, fructose is used to generate energy. However, fructose is also involved in lipogenesis, which is how fat is formed, unlike glucose. Fructose belongs to a group called ketose. Oligosaccharides are formed when fructose interacts with other monosaccharides. With the help of a glycosidic bond, Sucrose has a fructose molecule joined with a glucose molecule.

Uses of Fructose

  1. Crystalline fructose is used in the food industry to improve flavour.

  2. It is found in flavoured water, energy drinks, items that are low in calories, etc.

  3. In the manufacture of smooth, moist cookies, nutrition bars, low-calorie products, etc., fruit sugar is used.

Solved Examples

1. How Can We Obtain Glucose from the Starch?

Ans: Glucose can be obtained by the hydrolysis of starch in boiled and dilute H2SO4 at 393 K under pressure.

(C6H10O5)n (Starch or cellulose) + nH2O + H+ → nC6H12O6 (Glucose)

2. What are Some of the Common Differences Between Glucose and Fructose?

Ans: Glucose is a 6 membered ring, whereas the Fructose is 5 membered ring. Glucose produces less fat compared to fructose in our body. Glucose is an aldohexose, whereas the Fructose is a Ketohexose. 

3. What is Fructose Used for?

Ans: The basic natural sugar present in bananas, honey, and vegetables is fructose. Fructose is being used as a sweetener for a long time in its pure form and has benefits for certain groups of people, including individuals with diabetes and those seeking to control their weight. 


4. What are Some of the Physical Properties of Glucose?

Ans: Glucose is having the chemical formula C5H12O6 with a molecular weight of 180.16 g/mol. It’s a monosaccharide, with a density of 1.54 g/cm3.

5. What are the Properties of Fructose?

Ans: Compared to other carbohydrates, such as glucose, which has a melting point of 146 ° C, fructose has a lower melting point. The fructose compound has a molar mass of 180.16 mol / g and a density of 1.69 g / cm2. Refined fructose that is crystallized is pure and powdery. 

Fun Facts

  1. Fructose is being used as an artificial sweetener for the past 20 years in foods and beverages. 

  2. Natural fructose is a natural form of sugar. However, in junk foods, artificially produced fructose is used as a preservative, causing weight gain if so much is eaten across time.

  3. Fructose is sweeter than sucrose, but less is required to obtain the same sweetness by providing calorie reductions.

  4. Glucose is classified as a Hexose due to the presence of 6 carbons. 

  5. Pure glucose is crystalline or in the form of white powder. 

FAQ (Frequently Asked Questions)

1. Which Foods are Having Fructose in it?

Ans: Sugars, including fructose, are naturally present in all fruits, which is why fructose is also found in 100% of fruit juices. If the fructose part of sucrose (glucose + fructose) is not taken into account, the amount of fructose in the fruit section varies, depending on the type, from 1 to 6 g for citrus fruits, about 7 g for pineapple, and 3 to 10 g for apples and pears.

The fructose content of fruit juices, as predicted, represents the entire fruit composition and ranges from 0.5 to 7 g per 100 g of typical juices. 100 ml of orange juice, for example, contains 2.4 g of fructose, while 100 g of whole orange juice contains 2.2 g of fructose. The fructose content for apples is 6.7 g in the whole fruit and 5.5 g in the juice.

2. What are Sugars?

Ans: Sugars are carbohydrates that are chemically classified as monosaccharides and disaccharides that act as the body’s primary supply of nutrition. There are a variety of sugar types. In many foods, they exist both naturally and as ingredients. The most familiar sugar is sucrose. It is made of two simple sugars, fructose, and glucose. Fruits and vegetables contain fructose and glucose naturally. Inverted sugar, corn syrup, high fructose corn syrup, butter, lactose (milk sugar), and other syrups are other sugars used in foods. All those sugars except lactose break down into fructose and glucose during digestion. Lactose disintegrates into glucose and galactose.