Silica (silica) is a functional additive widely used in the food industry, primarily as a flowability improver and anti-caking agent. Its unique mechanism of action stems from its special physicochemical properties.

Basic Characteristics of Silica
Silica (chemical formula SiO₂·nH₂O) is a white amorphous powder with the following key characteristics:
Extremely small particle size: Original particle size <0.3μm, average particle size 11-110 nm
High specific surface area: 100-400 m²/g, which is the basis for its strong adsorption properties
Surface characteristics: Contains a large number of hydroxyl groups (-OH), exhibiting hydrophilicity
Physical state: Insoluble in water and common solvents, melting point as high as 1750℃
Structural characteristics: Porous structure, capable of forming a three-dimensional network structure
Mechanism of Action as a Flowability Improver

Hydrogen bond network formation: The hydroxyl groups on the surface of silica particles can connect with each other through hydrogen bonds, forming a three-dimensional network structure. In a static state, these network structures trap liquid molecules, making the system viscous; when agitated, hydrogen bonds break, the network structure disintegrates, and the liquid regains its fluidity.

Porous Structure Function: The porous structure allows fluid to pass through the gaps between particles, reducing fluid resistance within the material and thus improving fluidity.

Adsorption Performance: The high specific surface area allows it to adsorb moisture and oils, reducing particle adhesion and improving powder flowability.

Application Effects: In the pharmaceutical field, it shows that it can improve particle flowability, bulk density, and tablet hardness, and shorten disintegration time.

Mechanism of Action as an Anti-caking Agent:
Moisture Adsorption: It adsorbs moisture from the environment through its porous structure, preventing particle adhesion caused by moisture.

Physical Isolation: Tiny particles form a physical isolation layer in the powder material, preventing direct contact between particles. Surface hydroxyl group effect: Surface hydroxyl groups prevent direct bonding between particles via van der Waals forces.

Application effects: Proven in the rubber industry to prevent material clumping, this principle also applies to the food industry.
Applications in the food industry:
Powdered foods: such as milk powder, flavoring powder, coffee powder, etc., prevent clumping and improve flowability.
Sugar products: Adding to sugar powder prevents moisture absorption and clumping.
Food additives: Used as a carrier to improve the flowability of powdered additives such as flavorings and colorings.
Pharmaceutical applications: Although not food, its application principle as a flow promoter in tablet manufacturing can be referenced.

In summary, precipitated silica, through its unique physicochemical properties, plays an important functional role in the food industry, providing an effective solution for maintaining the quality and improving the processing performance of powdered foods.