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Views: 0 Author: Site Editor Publish Time: 2026-07-24 Origin: Site
Food-grade phosphates are widely used in modern industrial food processing. Due to their advantages such as improving food quality, enhancing food stability, increasing processing efficiency, and extending shelf life, they play an important role in various fields including meat products, dairy products, seafood, baking, and beverages.
Phosphorus is one of the most important macroelements for the human body. It also has profound significance for human bones, teeth, DNA, RNA, and ATP (adenosine triphosphate).
However, many people, lacking understanding, often react with fear upon hearing the word "food additive," believing that all food additives are harmful chemicals.
This article will systematically introduce food-grade phosphates from multiple perspectives, helping you build a complete understanding of phosphates and avoid misunderstandings.
Food-grade phosphates are a type of food additive, primarily used as humectants. Phosphate can also be used as a food ingredient or to fortify food nutrition. In food, it can also act as an acidity regulator, leavening agent, emulsifying salt, buffer, and metal ion chelating agent. It is a phosphorus-containing compound that complies with national regulations for use.
Generally, a single phosphate may have multiple functions and also possess certain nutritional value, thus it is widely used in the food industry.
Polifar provides 12 types of food-grade phosphates: Sodium Hexametaphosphate, Triicalcium Phosphate, Sodium Tripolyphosphate, Dipotassium Phosphate, Sodium Acid Pyrophosphate, Disodium Phosphate, Tetra Sodium Pyrophosphate, Monosodium Phosphate, Trisodium Phosphate, Monocalcium Phosphate, Diammonium Phosphate, and Dicalcium Phosphate.
The phosphates mentioned above require the reaction of phosphoric acid with different metal ions, such as sodium, potassium, calcium, and magnesium, to form salts or polyphosphates formed by the condensation of multiple phosphate groups.
The table below details the differences between food-grade phosphates, providing information on their uses, purity, heavy metal content, microbiological indicators, and applicable standards. You can see from this that food-grade standards are much stricter.
| Comparison Items | Food grade | Industrial Grade |
| Uses | Food processing | Chemical, Metal Processing, Water Treatment |
| Purity | High | Lower Standards |
| Heavy Metal Control | Extremely strict | Not Controlled by Food Standards |
| Microbiological Indicators | Requirements | No Requirements |
| Implementation Standards | FCC, GB, USP, etc. | Industrial Standards |
| Edible Value | Available | Not Allowed |
Modern food is diversified. To meet the requirements of appearance, quality, taste, and nutritional balance, appropriate additives are needed to maintain consumer appeal.
To improve the quality of meat and seafood products and prevent moisture loss during processing, which can lead to dryness, shrinkage, and quality degradation, sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP) are the phosphates with the strongest water-retaining properties. STPP and TSPP are commonly used as humectants in meat processing.
Adding superphosphate to meat or seafood reduces moisture loss during heating, cooking, and steaming. It also helps maintain the tender and moist texture of the meat, solving the problem of poor taste in processed foods. It is one of the effective food additives for improving product qualification rates and reducing production costs for enterprises.
In some meat products, such as sausages, ham, and luncheon meat, the fat, moisture, and protein need to be stabilized. Without phosphates, oil separation and product dehydration may occur.
Therefore, adding food-grade phosphates to meat products such as shrimp paste, luncheon meat, fish balls, and canned goods can improve protein solubility, enhance emulsification, fix oils, and stabilize moisture within the meat products.
In food processing, pH fluctuations can affect food quality, potentially leading to protein coagulation, system stratification, and taste deterioration. Phosphates have excellent pH buffering capacity, ensuring food quality and suppressing pH fluctuations.
When food maintains a pH balance during processing, products such as dairy products, beverages, and condiments become more stable during high-temperature sterilization and long-term storage. They are less prone to stratification, clumping, and sedimentation. The product's flavor and texture remain unchanged, resulting in a better appearance.
Water is indispensable in many food ingredients. Water can combine with metal ions such as calcium, magnesium, iron, and copper in raw materials, leading to sedimentation in beverages, browning of fruits and vegetables, blackening of meat products, and cloudiness and spoilage.
Adding appropriate amounts of food-grade phosphates, such as sodium pyrophosphate, sodium tripolyphosphate, and sodium hexametaphosphate (all three are polyphosphates), can complex free metal ions, blocking oxidation and crystallization reactions. This ensures beverages remain clear, prevents sedimentation, and effectively extends shelf life.
Phosphorus, calcium, and potassium are essential minerals for the human body. Phosphates can effectively and safely supplement the body with these nutrients, fortifying food's calcium and phosphorus content.
Furthermore, some ammonium and potassium-based phosphates can activate yeast or microorganisms, shortening fermentation cycles. When neutralized with baking soda, they result in baked goods that are fluffy, evenly textured, have a delicate taste, and a stable structure, suitable for large-scale production.
Powdered foods such as milk powder, protein powder, seasonings, and meal replacement powders are easily affected by moisture, leading to clumping and agglomeration, impacting customer experience and shelf life.
Adding appropriate amounts of phosphates, especially calcium-based phosphates, to these powdered products can optimize powder flowability and porosity, providing long-lasting anti-caking effects. It also provides dual nutrition, supplementing both calcium and phosphorus.
Before the 18th century, natural phosphorus was discovered. From the late 19th to the early 20th century, the food industry in Europe and America flourished. The baking industry used calcium phosphates to replace traditional yeast, doubling baking efficiency. During this period, phosphate products were limited in variety and application scenarios.
With the development of the Industrial Revolution, from the 1930s to the 1950s, continuous technological breakthroughs led to more diverse and abundant applications. Sodium tripolyphosphate, sodium pyrophosphate, and sodium hexametaphosphate gradually entered the food industry.
The industry discovered the moisturizing effect of polyphosphates on processed meat products and gradually formulated purity standards for the industry, strictly distinguishing between industrial-grade and food-grade usage restrictions.
The global food industry experienced rapid development from the 1960s to the 1990s. Frozen products, dairy products, beverages, and pre-prepared foods saw explosive growth. The phosphate industry saw mass production of all categories of sodium, potassium, calcium, and ammonium phosphates. The Codex Alimentarius Commission, the US FDA, and the European EFSA successively issued safety assessment reports and usage guidelines for phosphates.
Simultaneously, China introduced food-grade phosphate technology and gradually established a localized production system and national standard regulatory framework. Food-grade phosphates became one of the core additives in the domestic food industry.
The research and development of food formulations has increasingly highlighted the functional limitations of single phosphates. The rapid development of compound phosphate technology allows for complementary formulations of various types, avoiding the instability, astringency, and crystallization problems associated with single phosphates.
Simultaneously, the emergence of frozen baked goods, low-temperature meat products, and high-end dairy products is largely due to the development of specialized phosphates. The availability of anhydrous, slow-release, and high-purity phosphates has greatly satisfied the diverse product demands of the market.
The rise of global health awareness has led to a trend towards low-sodium and sodium-free foods since 2015. Potassium-based phosphates are replacing sodium phosphates, upgrading phosphates and reducing salt intake for a healthier lifestyle.
Continuous updates and improvements to regulations in various countries have shifted the focus from a crude addition method to precise quantitative, scenario-appropriate, and scientifically compounded addition. This allows food-grade phosphates to offer both greater safety and multifunctional advantages when added to food.
Food-grade phosphates are among the globally recognized food additives. Global authoritative bodies have strict regulations governing the use of phosphates. Major authoritative bodies include: China's GB2760 national standard system, the US FDA regulatory system, the EU EFSA regulatory system, and the Codex Alimentarius standard (a globally accepted benchmark).
These authoritative bodies may have slight differences in permitted varieties, scope of use, and dosage, but the overall principles remain consistent: ensuring food safety and harmlessness, and limiting their use in specific food categories and processes.
China's National Food Safety Standard for the Use of Food Additives (GB 2760-2024) clearly specifies the permitted varieties of food-grade phosphates. It defines the applicable categories and limits for phosphates in applications such as frozen seafood, seasonings, meat products, and baked goods.
The US FDA has established specific residue limits for products containing food-grade phosphates, demonstrating a high degree of precision in control. It also clearly defines limits for the purity, impurities, and heavy metals of various phosphates. The regulations also require standardized labeling of phosphate components on food packaging to ensure consumers' right to know. Commonly permitted food-grade phosphates include:
Phosphoric Acid
Monosodium Phosphate
Disodium Phosphate
Sodium Tripolyphosphate
Sodium Hexametaphosphate
Pyrophosphates
EU EFSA Regulation
The European Food Safety Authority (EFSA) uses E-numbers to label phosphates as food additives. Common phosphate numbers are:
E338: Phosphoric Acid
E339: Sodium Phosphate
E340: Potassium Phosphate
E341: Calcium Phosphate
E343: Magnesium Phosphate
E450: Pyrophosphate
E451: Tripolyphosphate
E452: Polyphosphate
EFSA is currently the most stringent phosphate regulatory system. It employs toxicological assessments to strictly limit daily phosphate intake to no more than 40 mg/kg body weight/day.
The Codex Alimentarius Commission (Codex) provides a reference for global regulations on the use of phosphates. It clearly defines the INS code, purity requirements, applicable food categories, and maximum permitted levels for phosphates in food. It also standardizes phosphate testing methods and residue determination criteria.
It requires that phosphates added to food at compliant doses be tested and found to be non-genotoxic, non-carcinogenic, and non-developmentally toxic, demonstrating reliable safety. The Codex standard is one of the core guidelines for cross-border food transactions globally and possesses high universality.
Food-grade phosphates are mainly classified into three categories according to the linkage of phosphate groups in their molecular structure: orthophosphates, pyrophosphates, and polyphosphates (also known as condensation phosphates or polymeric phosphates).
Orthophosphates mainly include:
Phosphoric acid (H₃PO₄)
Sodium dihydrogen phosphate
Disodium hydrogen phosphate
Trisodium phosphate
Potassium dihydrogen phosphate
Dapoxetine hydrogen phosphate
Calcium phosphate. These food-grade phosphates are the most basic, composed of single phosphate groups. Their characteristics include:
Superior water solubility (except for calcium salts)
Strong acid-base balance regulation ability
Stable buffering capacity
Orthophosphates are generally used in beverages, dairy products, baking, and nutritional fortification.
Common pyrophosphate products include:
Sodium pyrophosphate (SAPP)
Tetrasodium pyrophosphate (TSPP)
SAPP and TSPP are formed by the dehydration condensation of two phosphate groups. Key features include: superior moisturizing properties, higher protein solubility, excellent emulsifying performance, applicability as a leavening agent in baking, and controllable reaction rate. SAPP and TSPP are widely used in meat products, baking powders, etc.
Polyphosphate products include: Sodium tripolyphosphate (STPP), Sodium hexametaphosphate (SHMP), Potassium metaphosphate, and Potassium polyphosphate. Polyphosphates consist of multiple phosphate groups linked together to form chain or ring structures. Key features include: strong chelating ability for metal ions, strong water retention, resistance to lipid oxidation, effective improvement of frozen food quality, and prevention of protein denaturation. Polyphosphates are widely used in frozen seafood, meat products, cheese, beverages, and ready-to-eat foods.
The following diagram clearly shows the most suitable application scenarios for each type of phosphate. However, with the development of modern industrial technology, most single phosphates are no longer sufficient to meet the needs of the public. Compound phosphates can play a synergistic role, meeting the requirements of various food processing technologies.
| Classification | Molecular structure | Main functions: | Typical Applications |
| Orthophosphates | Single phosphate group | Acidification, buffering, nutrient fortification | Beverages, dairy products, baked goods |
| Pyrophosphates | Two phosphate groups | Water retention, emulsification, leavening | Meat products, baked goods, seafood |
| Polyphosphates | Multiple phosphate groups | Chelation, stabilization, freshness preservation | Frozen foods, meat products, cheese |
Common performance indicators of food-grade phosphates: phosphorus pentoxide content, aqueous solution pH value, water solubility and dissolution rate, thermal stability during processing, water retention capacity, powder fineness and flowability, and control of heavy metals and impurities.
The effective phosphorus pentoxide content determines the functional strength of phosphorus. However, this does not mean that the higher the phosphorus content, the higher the quality. High-purity, high-quality phosphates require low levels of other impurities and stable function. The optimal and most suitable phosphorus content should be selected based on the actual application scenario.
Different phosphates have different aqueous solution pH values, and their application scenarios will also differ. pH can affect the protein, enzyme activity, color, and flavor in food.
Acidic phosphates (MSP, MCP, SAPP) are mainly used for acid adjustment and leavening, and are suitable for neutral and acidic food systems. Neutral phosphates (DCP, TCP) are used to maintain the original acid-base system and are only used for anti-caking and nutritional fortification. Strongly alkaline phosphates (TSP, TSPP) cannot be used in acidic beverages and are only suitable for specific protein modification applications.
Phosphates that are readily soluble in water and dissolve quickly facilitate processing and reduce precipitation and clumping. Sodium and potassium phosphates (STPP, SHMP, DSP, DKP) have excellent water solubility and dissolve quickly, making them suitable for addition to beverages and low-temperature meat products. Acidic calcium salts such as MCP are soluble in water and suitable for baking water-soluble systems; DCP is slightly soluble, and TCP is almost insoluble in water, suitable only for solid powder foods and strictly prohibited from use in liquid systems.
Some products undergo high-temperature processing and sterilization. If the phosphate is not heat-resistant, it will lose its activity. Orthophosphates are usually chosen for high-temperature sterilization of dairy products and baked goods due to their extremely high heat stability. Pyrophosphates have moderate heat resistance and can be used in conventional baking processes. Long-chain polyphosphates (SHMPs) are weak and will become ineffective after prolonged high-temperature hydrolysis, making them more suitable for medium-to-low temperature, short-time processing.
Polifar classifies phosphates as humectants in its wide range of food additives. This demonstrates that water retention is one of the most important characteristics of phosphates. It helps maintain the moisture content of ham, canned goods, and other seafood, extending shelf life and preserving the appearance and texture of the food after processing.
Milk powder and protein powder are prone to absorbing moisture and spoiling. To prevent spoilage, calcium phosphate salts such as TCP and DCP are added. This allows for long-term storage and maintains food stability.
The heavy metal content determines whether a phosphate can be directly used in the food industry. Excessive heavy metal content is harmful to human health. More impurities indicate lower purity, affecting the effectiveness of the phosphate during processing.
1. Why is phosphorus important for living organisms?
Phosphorus is one of the core elements constituting life. It participates in the formation of genetic material, energy transfer molecules, cell membrane phospholipids, and bones and teeth. Without phosphorus, cells cannot store genetic information or produce energy.
2. What is the difference between sodium dihydrogen phosphate and disodium hydrogen phosphate?
The main difference lies in their pH and the sodium/hydrogen ion ratio:
Sodium dihydrogen phosphate (MSP): Contains 2 hydrogen atoms and 1 sodium atom. Its aqueous solution is acidic and is commonly used as an acid source or for acidity adjustment in baking and fermentation.
Disodium hydrogen phosphate (DSP): Contains 1 hydrogen atom and 2 sodium atoms. Its aqueous solution is slightly alkaline and is commonly used for water retention in meat, stabilization in dairy products, and acid-base buffering.
3. What are some common uses of phosphates in industry and agriculture?
Agriculture: Primarily used as fertilizers (such as superphosphate and diammonium phosphate, DAP), providing essential phosphorus nutrition for crop growth and promoting root development, flowering, and fruiting.
Food Industry: Widely used in food additives, for retaining moisture in meat, promoting leavening during baking, and preventing clumping.
Other Industries: Water treatment (water softening, corrosion and scale prevention), metal surface treatment (phosphating for rust prevention), detergent additives, and lithium battery materials.
4. How do people obtain phosphorus?
Humans/Animal: Cannot synthesize phosphorus themselves and must obtain it through dietary intake.
Industry and Agriculture: Primarily through the mining of natural phosphate rock (such as apatite), followed by chemical processing (such as sulfuric acid reaction or thermal reduction) to extract phosphoric acid, fertilizers, and various phosphate products.
5. Do proteins contain phosphorus?
Most common proteins do not contain phosphorus, but a special class of proteins does.
Basic Structure: The basic units that make up proteins (amino acids) are usually composed only of carbon, hydrogen, oxygen, and nitrogen (some contain sulfur), and naturally do not contain phosphorus.
Phosphoproteins: Some proteins undergo phosphorylation modification (binding phosphate groups) after synthesis, such as casein in milk and vitellin in egg yolks, which are rich in phosphorus. Therefore, high-protein foods (meat, eggs, milk, beans) are usually the main source of phosphorus in the diet.
Food-grade phosphates have powerful functions and roles, shining brightly in various food industries. As long as food companies add them in compliance with regulations, they will not cause harm to the human body. If you need to learn more about phosphates, please continue to follow Polifar's updates. We will regularly update to bring you more cutting-edge and beneficial phosphate products and knowledge, as well as usage suggestions. Polifar continuously provides customers with one-stop solutions, offering the most worry-free sourcing experience in China!
