Concept and Characteristics of Modified Starch

In order to improve the performance of starch and expand its application range, physical, chemical or enzymatic treatments are used to introduce new functional groups into starch molecules or change the size of starch molecules and the properties of starch granules, so as to change the natural properties of starch (e.g., the pasting temperature, thermal viscosity and its stability, freezing and thawing stability, gelation, film-forming, transparency, etc.), and to make it better suited to the requirements of certain applications. This kind of starch that has undergone secondary processing to change its properties is collectively called modified starch.

Through appropriate modification and processing of modified starch compared with ordinary starch, most of them have high paste transparency, low pasting temperature, starch paste viscosity and stability, coagulation is small, film-forming properties, frost resistance and acid resistance, alkali resistance and mechanical resistance and many other excellent characteristics.

Application of modified starch in foodstuffs

1. In rice and noodle products, modified starch is mainly used for its good thickening, film-forming, stabilizing and pasting properties. The main modified starch used are esterified starch and hydroxypropyl starch.

1) The fried instant noodles with modified starch have crispy structure and low oil absorption, and the quality and storage stability of the products are better.

2)In instant noodles, it can improve the rehydration, chewiness and elasticity of noodles and reduce the cooking time

3) Adding modified starch to pasta pastries can reduce the oil absorption, improve the crispiness of pasta, and prolong the storage time of products

4) In the production of rice flour as a tissue forming agent and viscosity agent, it can increase the transparency and smoothness of the products, reduce the stickiness and improve the taste.

2. In bakery products, it mainly utilizes modified starch’s good film-forming property, high-temperature swelling property and stability.
(1) Used as ghee substitute in cake and icing production to provide good capacity and structure and reduce human fat intake.

(2) Glazing agent in baked goods, can form a good, clear and bright film, instead of expensive protein and natural gum.

3) As stabilizer and thickener in fruitcake, pie and filling, providing smooth and short filament structure of the product, preventing delamination and bursting of filling.

In waffles, whipped biscuits and cookies, it can produce crispy texture, excellent color and better taste. In pasta products, it can also increase the firmness and cooking resistance of the products.

Products such as thin and crispy cookies and rice krispies require starches with a certain degree of swelling. Pregelatinized starch is the raw material for these products and is superior to adding ordinary starch. The reason for this is that some of the starch in the mixture blanks made with pregelatinized starch has absorbed water, and when baked, a large amount of water-frozen starch granules will bubble out, resulting in swelling. On the contrary, if ordinary starch is used, the water will only start to be absorbed during baking, so it will not be easy to achieve the purpose of crispness. Sometimes modified pre-gelatinized starch is used to achieve better results.

3. In the application of frozen food, modified starch in most frozen food mainly plays the role of thickening, improving texture, anti-aging and improving the sensory quality.

Such as soup dumplings after freezing the skin is easy to crack, not to mention repeated freezing and melting. In the production of dumplings in the glutinous rice flour to add about 5% of etherified starch, can play a bonding and wetting effect, can effectively avoid skin rupture and starch regeneration, to reduce the cooking phenomenon of paste soup, reduce the amount of solids in the soup.

4. In the application of leisure food, the main use of modified starch good adhesion, swelling type, brittle properties and fluffy structure, commonly used modified starch has pre-gelatinized starch, etherified starch and compound modified starch
(1) In extruded puffed food, modified starch can make the products have good puffiness and structure, the strength and brittleness of the products are also improved, and the products have uniform organization and high output rate, and at the same time, it can increase the functional fiber composition.

(2) In microwave puffed food, modified starch can control the volume and structure of the products, so that the products have uniform pores.

(3) In crunchy peanuts, modified starch can improve the organization of crunchy skin, giving crunchy skin light, crispy, brittle and fluffy structure.

(4) In other foods, modified starch can also play a good role!

The development trend of modified starch

1、Development of new functional modified starch
Functional modified starch is mainly used in food, medical, pharmaceutical, daily-use chemical and other industries, referring to modified starch with certain health effects and physiological functions on the human body, as well as environmentally friendly starch-based slow-release carriers, adsorption materials, biodegradable materials, such as resistant starch, slow-digesting starch, porous starch and so on.

The output of this kind of modified starch is not as big as that of common modified starch, but it can significantly improve the quality and grade of processed products with high added value, which is the current development trend of domestic and foreign modified starch research.

2、Establish and improve the nutritional value of modified starch and food safety evaluation system
Edible modified starch produced in developed countries has long been recognized by WHO and FAO Expert Committee on Food Additives, and many products have been examined by FDA, and the corresponding usage limit and usage have been formulated. Although China’s “Food Additives Manual” also has relevant content on the dosage and usage of edible modified starch, there is less content on the nutritional value and safety of edible modified starch, and the safety evaluation system of edible modified starch is not sound.

In order to improve the safety of modified starch, the research on nutritional value of modified starch should be deepened, and the safety evaluation system of modified starch should be established and improved. There is also much room for research on the production process of modified starch, production equipment and the development of new products in China.