What Are the Ingredients in Glucose Syrup?

January 13, 2026 •

3 min read

Many people are surprised to learn that glucose syrup is derived primarily from the starch of plants like corn, wheat, or potatoes. The fundamental ingredients in glucose syrup are a starch source and water, which are then processed using specialized enzymes or acid.

Quick Summary

Glucose syrup is made from starch derived from various plants such as corn, wheat, or potatoes. This starch is broken down into a mixture of sugars, including glucose and maltose, through hydrolysis using water and enzymes.

Key Points

Starch Source: The primary ingredient is starch, commonly sourced from corn, wheat, potatoes, or rice.
Water: Water is essential for the hydrolysis process that breaks down the starch.
Enzymes or Acid: Specialized enzymes, like amylase, or dilute acid are used to convert the starch into sugars.
Final Composition: The final syrup is a concentrated solution of various sugars, including glucose, maltose, and higher saccharides.
Dextrose Equivalent (DE): The sweetness and viscosity of the syrup depend on its DE value, which indicates the extent of starch hydrolysis.

The Primary Building Blocks of Glucose Syrup

At its core, glucose syrup is a concentrated liquid solution of saccharides—or sugars—that is derived from the hydrolysis of starch. The term 'ingredients' in this context can be a bit misleading, as the process involves transforming a raw material rather than simply mixing components. The key is the transformation of a starchy substance into its simpler sugar constituents through a chemical reaction.

The Role of Starch

The most significant ingredient is the starch itself, which serves as the raw material. While corn is the most common source, especially in the United States where the product is known as corn syrup, other plants can be used depending on regional availability.

Common Starch Sources for Glucose Syrup:

Maize (Corn): The most prevalent source globally.
Wheat: A common source in Europe.
Potatoes: Used as a source, particularly for industrial production.
Rice: Another alternative starch source.
Cassava and Barley: Used less frequently, but still viable sources.

Water and the Hydrolysis Process

Water is the other critical ingredient, serving as the medium in which the starch is dissolved and broken down. The hydrolysis process, which means 'water-splitting', uses water to break the long chains of glucose molecules that make up the starch. To facilitate this breakdown on an industrial scale, either enzymes or dilute acid is introduced.

Enzymes or Acid: The Conversion Catalyst

To convert the complex starch molecules into simpler sugars, manufacturers employ a catalyst. Historically, this was done using acid hydrolysis, but modern production overwhelmingly relies on enzymatic hydrolysis.

Enzymatic Hydrolysis: This method uses specific enzymes to control the breakdown of starch. Alpha-amylase is initially used to break the starch into shorter chains (oligosaccharides), and then glucoamylase converts these chains into individual glucose molecules. This allows for a more controlled reaction and avoids the bitter byproducts of acid conversion.
Acid Hydrolysis: The older method uses dilute hydrochloric or sulfuric acid at high temperatures to break down the starch. While cheaper, it produces more variable results and can lead to unwanted flavors.

The Final Saccharide Mixture

The end product is not just pure glucose but a mixture of different sugars. The exact composition depends on the degree of hydrolysis, which is measured by the dextrose equivalent (DE). A higher DE means a higher proportion of simple sugars like glucose, while a lower DE indicates more complex chains, or oligosaccharides.

Typical Saccharide Composition (Example for a Confectioner's Syrup):

Glucose (Dextrose): The simplest sugar, providing sweetness.
Maltose: A disaccharide made of two glucose units.
Maltotriose: A trisaccharide of three glucose units.
Higher Saccharides: Longer chains of glucose molecules.

Glucose Syrup vs. Corn Syrup

While the terms are often used interchangeably, there is a technical distinction, especially in North America where corn syrup is a common retail product.


Feature	Glucose Syrup	Corn Syrup
Starch Source	Can be from corn, wheat, rice, potatoes, etc.	Derived exclusively from cornstarch.
Terminology	A broader term for any starch-hydrolyzed syrup	A specific type of glucose syrup.
Regional Use	Widely used worldwide, especially in Europe for syrups from wheat.	Most common term in the United States.
Usage Scope	Used for a wider variety of industrial and food applications.	Primarily used in baking and confectionery.
Gluten Content	Most versions are gluten-free due to processing, even wheat-derived ones.	Gluten-free as corn is a non-gluten grain.

Conclusion: From Starch to Sweetener

Understanding what are the ingredients in glucose syrup reveals a fascinating transformation from simple plant starch into a versatile food additive. The primary ingredients are a carbohydrate-rich starch source and water, with enzymes or acid acting as a catalyst. The resulting syrup's composition of glucose, maltose, and other saccharides is carefully controlled to produce specific levels of sweetness and viscosity for various applications in the food industry. This manufacturing process, refined over centuries, explains how a humble plant starch can become the basis for a sweetener that prevents crystallization, retains moisture, and enhances the texture of countless products. For more detailed information on the industrial process, Wikipedia provides an excellent overview of the history and methods involved.

Frequently Asked Questions

No, glucose syrup is not just simple table sugar (sucrose). It is a concentrated liquid solution containing a mixture of various saccharides, including glucose, maltose, and other higher sugars, all derived from the hydrolysis of starch.

Corn syrup is a specific type of glucose syrup made exclusively from cornstarch. Glucose syrup is a broader term for a syrup made by hydrolyzing starch, which can come from various plants like corn, wheat, rice, or potatoes.

Yes, extensive enzymatic and chemical processing of wheat-derived glucose syrup removes most of the gluten. The final product almost always contains less than 20 parts per million of gluten, the threshold for being considered gluten-free in many regions.

DE stands for Dextrose Equivalent and measures the extent of starch hydrolysis. A higher DE indicates a greater breakdown into simple sugars like glucose, resulting in a sweeter, less viscous syrup.

Yes, it is possible to make a version of glucose syrup at home by heating a mixture of cornstarch, water, and an acid like lemon juice or cream of tartar. This process mimics the industrial acid hydrolysis.

It is used in candy making to prevent sugar crystallization, which helps create a smooth texture. It also controls viscosity and provides a sweetening agent that enhances flavor and mouthfeel in products like caramel and hard candies.

The most common starch sources are corn (maize), wheat, potatoes, and rice. Less common sources include barley and cassava, depending on industrial and regional availability.