Food-grade sodium carboxymethyl starch is a thickening agent, stabilizer, and emulsifier widely used in the food industry. Its unique chemical structure and physical properties make it play an important role in food processing. At the same time, as a food additive from natural sources, its safety is also a concern.

　　I. Characteristics

　　Food-grade sodium carboxymethyl starch is a white or slightly yellowish powder, odorless, tasteless, non-toxic, and not easily moldy. It is easily soluble in water, forming a colloidal solution, and is stable to light and heat. It is insoluble in ethanol, ether and other organic solvents. In aqueous solution, sodium carboxymethyl starch exhibits good thickening, suspending, emulsifying, stabilizing, shape-retaining, film-forming, puffing, and freshness-preserving properties. These properties give it a wide range of applications in food processing.

　　II. Applications

　　Thickening effect: Sodium carboxymethyl starch can significantly increase the viscosity of food, improving the taste and texture. Therefore, it is often used as a thickener in foods such as jams, candies, and beverages.

　　Suspending effect: By increasing the system viscosity, sodium carboxymethyl starch can prevent the sedimentation or aggregation of particles in food, thus playing a suspending role. This property makes it widely used in foods that need to maintain a suspended state for a long time, such as certain beverages or seasonings.

　　Emulsifying effect: Sodium carboxymethyl starch contains dissociable anionic groups, allowing it to align and stabilize emulsions at the oil-water interface. Therefore, it is often added to foods containing oils and fats, such as salad dressings or baked goods, to prevent oil and water separation.

　　Stabilizing effect: Sodium carboxymethyl starch can improve the stability of food and extend its shelf life. For example, adding sodium carboxymethyl starch to processed meat products can reduce drying and extend shelf life.

　　III. Safety

　　The safety of food-grade sodium carboxymethyl starch is considered harmless within the normal range of use. However, excessive intake may have adverse effects on the body, such as digestive discomfort. Therefore, its usage should be strictly controlled in food processing to ensure compliance with food safety regulations. In addition, people with a history of special diseases or allergic reactions should be cautious when consuming foods containing sodium carboxymethyl starch and consult a doctor if necessary.

　　In summary, food-grade sodium carboxymethyl starch plays an important role in food processing due to its unique chemical structure and physical properties. However, its usage should be strictly controlled to ensure food safety and quality. At the same time, consumers should also pay attention to checking the ingredient list when choosing foods, understanding whether they contain food additives such as sodium carboxymethyl starch, and making reasonable choices based on their own situation.