The properties and common uses of cross-linked starch
Cross linked starch is an important starch derivative with excellent physicochemical and functional properties. Below is a detailed explanation of the overview, properties, and applications of cross-linked starch from three aspects:
1、 Overview of Cross linked Starch
Cross linked starch is a type of modified starch prepared through cross-linking reaction, whose molecular structure has been altered. Crosslinking agents are key substances for achieving crosslinking reactions, and commonly used crosslinking agents include phosphorus oxychloride, sodium tripolyphosphate, adipic acid, hexametaphosphate, etc. These crosslinking agents react with hydroxyl groups in starch molecules to form groups such as diethyl ether bonds and diester groups, thereby connecting two or more starch molecules to form a high polymer with a spatial network structure.
2、 Properties of cross-linked starch
Shear resistance: Cross linked starch has good shear resistance and can withstand large shear forces during processing, making it difficult to gelatinize.
Acid resistance: Cross linked starch is stable in acidic environments and is not easily decomposed by acid, making it suitable for use in acidic foods.
Mechanical processing resistance: Due to its shear resistance and stability, cross-linked starch is not easily damaged by mechanical forces during processing, which can improve processing efficiency and product quality.
Gel performance: cross-linked starch has good gel performance and can form a stable gel system, which is widely used in food, medicine and other fields.
Reduced water absorption capacity: Compared with ordinary starch, cross-linked starch has a slightly reduced water absorption capacity.
Stability enhancement: The strength of cross-linking chemical bonds is much higher than that of hydrogen bonds, enhancing the strength of particle structure, inhibiting particle expansion, rupture, and viscosity decrease. Epoxy chloropropane crosslinks into ether bonds, with high chemical stability. The resulting crosslinked starch has high stability against acid, alkali, shear, and enzymatic reactions.
3、 The use of cross-linked starch
Food processing: Cross linked starch has good shear resistance and stability, and can be used as a thickener, stabilizer, adhesive, etc. in food processing. For example, it can act as a stabilizer when making foods such as jam, juice, yogurt, cheese, etc; It can act as a thickener and adhesive in the production of bread, pastries, and other foods. In addition, because cross-linked starch has good gel properties, more stable and long-term starch products can be produced.
In the pharmaceutical field, cross-linked starch can be used to make drug carriers and biomedical materials. By encapsulating drugs in microspheres or microcapsules formed by cross-linked starch, controlled release and targeted delivery of drugs can be achieved, improving drug efficacy and reducing side effects. Meanwhile, cross-linked starch can also be used to produce biomedical materials such as tissue engineering scaffolds and drug controlled release carriers.
Paper and textile industries: Cross linked starch can be used for paper coating, pulp additives, and textile sizing. Due to its good shear resistance and stability, it can improve the surface strength and printing adaptability of paper; In textile sizing, the wear resistance and wrinkle resistance of fabrics can be improved.
Construction and building materials industry: Cross linked starch can be used to make coatings, adhesives, cement additives, etc. Due to its good shear resistance and weather resistance, it can improve the adhesion and durability of coatings; As an adhesive, it can improve the bonding strength and water resistance of materials; As a cement additive, it can improve the compressive strength and durability of concrete.
In the field of environmental protection, cross-linked starch has good biodegradability and can be used to make environmentally friendly materials such as biodegradable plastic bags and tableware; It can also be used as a water treatment agent, soil amendment, etc., which helps to solve environmental pollution problems.
Other fields: Cross linked starch can also be applied in daily necessities, cosmetics, petroleum and other fields. For example, it can be used as a thickener and stabilizer in cosmetics; In the petroleum industry, it can be used as a thickener and stabilizer for drilling fluids and fracturing fluids.
Overall, cross-linked starch is an important type of modified starch, and its unique physicochemical and functional properties make it widely used in fields such as food, medicine, chemical engineering, materials, and environmental protection. With the continuous progress of science and technology and the expansion of application fields, the application prospects of cross-linked starch will be even broader.