Silica is widely used in the food industry as a thickening agent, stabilizer, anti-caking agent, and adsorbent. It can significantly improve food texture, extend shelf life, and enhance product stability.  It is considered safe when used at appropriate dosages and has been approved for use by food safety agencies in several countries.

I. Core Applications of Silica in the Food Industry
1. Food Thickening and Stabilization
Dairy products: Silica can be used as an emulsifier and stabilizer in dairy products, improving their quality and stability, extending shelf life, and improving texture and mouthfeel, increasing gloss and smoothness.
Beverages: In beverages, it acts as a suspending agent, emulsifier, and stabilizer, increasing viscosity and emulsification, improving texture and mouthfeel. It is particularly suitable for removing suspended impurities and improving product stability in fruit juice and beverage production.
Condiments and sauces: In products such as soy sauce, syrups, and jams, silica provides better flowability and viscosity, making them easier to use and consume, while also enhancing suspension and color stability.
2. Anti-caking and Dispersing Functions
Powdered foods: Silica can be used as a stabilizer and anti-caking agent in powdered foods, increasing their stability and shelf life, preventing clumping and caking, and is particularly suitable for powdered foods such as salt and sugar.
Bread and pastries: In bread and pastries, silica can increase the extensibility of dough, improve its plasticity, and give baked goods a unique color, texture, and flavor, preventing flour from clumping.
3. Adsorption and Purification
Impurity removal: Silica has a high specific surface area and porosity, allowing it to adsorb turbidity and color impurities in food, making the food clear and transparent and improving visual appeal.
Oil control: In chocolate production, silica can prevent fat crystallization in chocolate, maintaining a delicate and smooth texture, while also adsorbing excess moisture in food and regulating food texture.
Odor removal: As a deodorizer, silica can remove odors from food, improving food quality and safety. 4. Preservation and Shelf Life Extension
Moisture Control: The hygroscopic properties of precipitated silica effectively control the moisture content in food, preventing spoilage due to excessive moisture.
Oxidation Inhibition: By adsorbing moisture and oxygen, precipitated silica can slow down food spoilage and oxidation, thereby increasing the shelf life of food.
Microbial Inhibition: In food packaging, precipitated silica is used as a desiccant, moisture absorbent, and mold inhibitor, effectively protecting food from moisture and mold.

II. Safety Assessment of Precipitated Silica
1. Toxicological Study Results
Acute Toxicity: Studies show that using precipitated silica in appropriate amounts does not cause significant acute toxic side effects on human health.
Long-term Exposure: Although precipitated silica has not shown significant severe toxic reactions under short-term exposure, there is a certain degree of potential risk with long-term exposure. It is recommended to prevent inhalation and contact during use.
Carcinogenicity: According to the International Agency for Research on Cancer (IARC) classification, precipitated silica is classified as a Group 4 substance, meaning "not classifiable as to its carcinogenicity to humans."
2. Safe Usage Dosage
Appropriate Use: Studies show that using precipitated silica in appropriate amounts does not cause significant toxic side effects on human health, but attention should be paid to controlling the intake to avoid adverse reactions caused by excessive consumption.
Risk of Overdose: Excessive intake may lead to gastrointestinal problems, such as indigestion and bloating. Therefore, the amount added to food must be strictly controlled.
3. Regulation and Standards
International Recognition: The European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA) have both established usage restrictions and regulations for precipitated silica, requiring strict safety assessments.
Food-Grade Standards: Food-grade precipitated silica refers to precipitated silica that has been strictly screened and processed to meet relevant national or regional food safety standards, usually having higher purity and lower impurity content.

III. Precautions and Suggestions for Use
Control Usage Amount: When using precipitated silica in food, relevant regulations and standards should be strictly followed to control the amount used and avoid excessive use.
Avoid Inhalation Risk: Due to the small size of precipitated silica particles, which are easily suspended in the air, inhalation should be avoided as much as possible to reduce potential damage to the respiratory system. Prevent skin contact: Silica may cause some skin irritation; it is recommended to wear appropriate protective gloves or clothing to minimize contact.
Compliance labeling: Food manufacturers should clearly indicate ingredient information and usage restrictions on product packaging to provide consumers with sufficient information.
Caution for specific groups: Some individuals may be allergic to certain components in foods containing silica; therefore, individual differences and allergy risks should be considered during use.
Thanks to its unique physicochemical properties, silica plays an irreplaceable role in the food industry, with wide-ranging applications from improving food texture to extending shelf life. Under reasonable conditions of use, silica has been proven to be a safe food additive, but it is necessary to control the amount used and follow relevant safety standards to ensure consumer health. With the continuous development of food technology, the application prospects of silica in the food industry will be even broader.