Starches are modified to enhance their performance in different applications. Starches may be modified to increase their stability against excessive heat, acid, shear, time, cooling, or freezing, to change their texture, to decrease or increase their viscosity, to lengthen or shorten gelatinization time or to increase their visco-stability.
Modified starch is native starch that has been treated so that its properties have been changed. Native starch belongs to the carbohydrates and consists of glucose molecules. Depending on which plant it comes from, one can distinguish between corn starch, potato starch or wheat starch, among others. These starches undergo one of three types of modification to produce modified starches.
Types of modified starch:
Depending on how the starch has been modified, a distinction can be made:
Physically modified starches:
Are formed by exposing the starch to heat, pressure, electricity or radiation. This results in a change in the spatial structure of the chains. Physically modified starch is added to foods, but is not treated as an additive, but as a food ingredient with a thickening function, and therefore does not have an ‘E’ number.
Starch is subjected to chemical processes such as oxidation, esterification or etherification. The resulting starches are treated as food additives with the numbers E1400-E1500.
Enzymatically modified starches:
the modifications are carried out with the help of enzymes, resulting in maltodextrins. Like physically modified starches, they are recognized as food ingredients. All these modifications do not interfere with the structure of DNA, so modified starches do not belong to genetically modified foods (GMOs).
Properties of modified starch:
Modification of starch is mainly aimed at obtaining additional desirable properties that could be useful in industry. Modified starches are in the form of a white powder and are well soluble in both cold and hot water. In addition, unlike native starches, they resist the process of starch retrogradation. This prevents undesirable changes in the consistency of the products. Modified starches are also characterized by the fact that they are stable in alkaline and acidic environments.
In general, modified starches have texturizing properties – they have the ability to bind water, gelatinize and prevent bulk product caking.
Applications of modified starch:
Modified starch has many properties that can be used in the food industry. This is the most popular application, but modified starches are also useful in other industries. They are used in:
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food industry,
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pharmaceutical industry,
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cosmetic industry,
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paper industry,
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chemical industry.
