Oxidized Starch E1404(CAS#65996-62-5)–Modified Food Thickener & Paper Coating Agent

1. Properties:

• Appearance and Physical Form: Oxidized starch (E1404, CAS#65996-62-5) is supplied as a white to off‑white free‑flowing powder or granules. Pregelatinised grades are available as flakes, amorphous powder, or coarse particles for instant thickening applications. The powder is odourless and tasteless, with a very slight characteristic starch odour when handled in bulk.
• Solubility: The product is insoluble in cold water (unless pregelatinised) and insoluble in ethanol (96%). Upon heating in water to typical processing temperatures, oxidized starch forms a clear, translucent to transparent viscous colloid with reduced viscosity compared to native starch, facilitating processing at higher solids concentrations.
• Chemical Properties: Oxidized starch is an anionic modified starch produced by treating native starch (derived from corn, waxy maize, tapioca/cassava, potato, or wheat) with an oxidizing agent—typically sodium hypochlorite (NaOCl)—under alkaline conditions below the gelatinization temperature, in accordance with Good Manufacturing Practice (GMP). The oxidation process selectively modifies the primary alcohol groups at the C‑6 position of the glucose units and some secondary hydroxyl groups, converting them into carbonyl (–C=O) and carboxyl (–COOH) groups. The degree of oxidation is controlled by the amount of hypochlorite used, the reaction temperature, pH, and duration.
  • Carboxyl and Carbonyl Content: The introduction of carboxyl groups imparts anionic character and decreases the pasting temperature. Hypochlorite oxidation generally increases the contents of carbonyl and carboxyl groups in starch while decreasing starch viscosity. Mildly oxidized starch (≤1.0% chlorine) retains higher peak and final viscosities, while more extensive oxidation produces lower‑viscosity, highly dispersible starches. The carboxyl group content of commercial food‑grade oxidized starch is typically ≤1.1 g/100g.
  • Viscosity Reduction and Clarity Improvement: The introduction of charged carboxyl groups disrupts inter‑ and intra‑molecular hydrogen bonding, reducing the tendency of the starch chains to reassociate (retrogradation). This results in a significant reduction in hot paste viscosity, improved paste clarity (transparency), and a cleaner flavour profile with no residual starchiness or off‑taste. These properties make oxidized starch particularly suitable for applications where a low‑viscosity, high‑clarity paste is required.
  • Film‑Forming Properties: Oxidized starch exhibits excellent film‑forming capabilities. The films are transparent, flexible, and have good adhesive strength. The lower molecular weight and increased hydrophilicity of oxidized starches result in films with higher water solubility and faster dissolution rates compared to those from native starch. This property is exploited in paper coating, adhesive, and biodegradable packaging applications.
  • Thermal and Shear Stability: The cross‑linked structure imparted by oxidation enhances thermal and shear resistance compared to native starch, maintaining viscosity under high‑temperature processing conditions (e.g., canning retort up to 121°C) and during mechanical mixing.
  • Pregelatinisation: Oxidized starch is available in pregelatinised grades that swell and thicken in cold water without the need for heating, providing instant viscosity for ready‑to‑mix food products and industrial formulations.
  • Digestibility and Caloric Value: Oxidized starch is hydrolysed by digestive enzymes and fermented by intestinal microbiota. In vitro digestibility by pancreatin is approximately 10–15% lower than that of unmodified starch, but no significant difference in caloric value has been observed compared to native starch. Feeding studies in rats have shown that digestibility coefficients and body weight gain for oxidized starch are practically indistinguishable from those obtained for wheat starch or corn starch, with no tissue damage associated with consumption.
  • Regulatory Status: Oxidized starch is approved as a food additive with the INS number 1404 and has been evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). An Acceptable Daily Intake (ADI) of “not specified” has been established—the highest safety category, indicating no safety concern at any level of intake. The product is listed as GRAS (Generally Recognized as Safe) by the US FDA under 21 CFR §172.892 and is authorised as a food additive E1404 in the European Union under Regulation (EC) No 1333/2008.

2. Applications:

Food & Beverage Industry (Primary – E1404 Thickener, Stabilizer, Binder & Emulsifier):

• Canned Foods and Retorted Products (Soups, Canned Vegetables, Ready Meals): Oxidized starch provides excellent heat stability, preventing thinning and syneresis during high‑temperature retort processing (121°C). It maintains consistent viscosity and texture throughout shelf life, even in low‑pH formulations such as tomato‑based products. The solution of soluble oxidized starch can retain transparency in long‑term storage, making it suitable for canned soups and confectionery products that need clarity. Typical use level: 1–4%.
• Sauces, Dressings and Condiments (Ketchup, Mayonnaise, Salad Dressings, Gravy, Oyster Sauce, Barbecue Sauce): The starch functions as an anionic thickener and stabiliser, providing desirable body and mouthfeel without masking flavour. High paste clarity ensures an appealing, glossy appearance. It maintains consistency even under conditions of heating, cooling, or freezing. E1404 assists in blending oil and water phases, improving dispersion and creating smooth textures in emulsions.
• Confectionery and Bakery Fillings (Gummies, Caramels, Pastry Creams, Fruit Fillings, Gums): Oxidized starch serves as a pan coating agent for confections and gums, forms clear glazes, and functions as a gum Arabic replacer or extender. It provides high clarity, good gel strength, and smooth texture for fruit fillings, preventing boil‑out during baking. In confectionery, it can replace gelatin or gum arabic and reduces sugar content in formulations. Acetylated oxidized starch (a derivative) produces a gummy, clear jelly ideal for soft confectionery.
• Dairy Products and Desserts (Yoghurt, Pudding, Cream, Custards, Flavoured Milk, Processed Cheese, Ice Cream): Oxidized starch improves texture, creaminess, and freeze‑thaw stability while preventing whey separation. It provides excellent viscosity control and water retention for dairy desserts.
• Frozen Foods (Frozen Ready Meals, Frozen Vegetables in Sauce, Frozen Meat Products, Ice Cream): The starch provides good freeze‑thaw stability, maintaining viscosity and texture after multiple freeze‑thaw cycles without water separation (syneresis). It is widely used in quick‑frozen microwave noodles and fresh‑keeping wet noodles.
• Bakery Products (Breads, Cakes, Pastries, Glazes): Oxidized starch improves dough workability, water retention, and freeze‑thaw stability, maintaining freshness and extending product shelf life. It can be used to adjust dough consistency and reduce cooking time.
• Instant Noodles and Pasta: In noodles, oxidized starch reduces dehydration time, improves elasticity, and provides a firm, springy texture. It is widely used in quick‑frozen microwave noodles and fresh‑keeping wet noodles.
• Baby Food and Weaning Formulae: E1404 is approved for use in infant formulas and complementary foods for infants and young children as a safe thickening agent, providing appropriate viscosity for safe swallowing and improved texture.
• Meat Products (Sausages, Processed Meats, Canned Meat): Oxidized starch functions as a binder and water‑holding agent in processed meat formulations, improving yield, texture, and juiciness while extending shelf life by reducing moisture loss.
• Gluten‑Free and Clean‑Label Products: As a plant‑derived, non‑GMO, non‑allergenic, vegan ingredient, oxidized starch is widely used in gluten‑free bakery and clean‑label formulations to replace the functional properties of gluten.
• Instant Beverages and Desserts: Pregelatinised grades dissolve in cold water, providing instant thickening for powdered drink mixes, instant dessert formulations, and beverage creams.

Paper & Pulp Industry (Primary – Surface Sizing & Coating):

• Paper Machine Surface Sizing Agent: Oxidized starch is widely used as a surface sizing agent applied at the size press. It improves paper surface strength, stiffness, printability, smoothness, and resistance to ink feathering. It enhances bending stiffness, porosity reduction, and dry pick resistance. The viscosity of the product can be specially processed within the range required by the user, with high cost performance.
• Paper Coating Binder (Pigment Coating): E1404 functions as a binder and adhesive in paper coating formulations, enhancing surface strength, printability, gloss, and ink holdout. It can be used as a coating binder to improve the physical properties of paper and board, and as a pigment binder for calcium carbonate, clay and titanium dioxide pigments in coating colour formulations. It makes high‑concentration cooking possible, as its paste viscosity is low and maintains its properties even when used for a long period of time due to excellent stability.
• Corrugated Cardboard Adhesive: Oxidized starch is used as an adhesive in corrugated paper production. The paste liquid has strong cohesive force and high stability. Long‑term use will not cause excessive fluctuations in viscosity, ensuring the stability of ring compressive strength and water absorption of corrugated paper. It has good water resistance and is not easy to absorb moisture.
• Wet End Additive: Used as a wet additive in the paper machine wet end to improve retention, drainage, and sheet formation.
• Spray Bonding: The product can be prepared as a 2–6% suspoemulsion, sprayed between paper layers, and gelatinised during the heating process to provide bonding. Typical usage: 20–60 kg per ton of paper, with high‑strength papers up to 100 kg per ton.

Textile Industry:

• Warp Sizing Agent: Oxidized starch is used in textile warp sizing to improve yarn strength, reduce hairiness and breakage during weaving, and enhance fabric quality. It is easy to gelatinise and the gelatinization temperature is easy to control. The paste liquid has good film‑forming property (more uniform than native starch), strong adhesive force, and high stability. Low viscosity allows for effective processing without excessive stiffening.
• Textile Printing Thickener: E1404 functions as a thickener in textile printing pastes, providing sharp pattern definition, uniform dye transfer, and easy wash‑off after printing.
• Fabric Finishing: The starch imparts stiffness and body to finished fabrics.

Oil & Gas Industry – Drilling and Cementing (Secondary – Fluid Loss Control):

• Water‑Based Drilling Fluids (WBM) – Fluid Loss Reducer: Starch derivatives, including partially oxidized starch, have been found to be effective water loss control additives in clay‑free wellbore fluids. The starch can be added to the wellbore fluid in either gelatinised or ungelatinised form. Oxidized starch reduces filtrate loss into permeable formations by forming a thin, low‑permeability filter cake on the wellbore wall.
• Cementing Slurries (Oil Well Cementing): Oxidized starch functions as a fluid loss control additive and rheology modifier in oil well cementing operations, reducing filtrate invasion into permeable formations, preventing gas migration, and ensuring a reliable cement sheath for long‑term zonal isolation.
• Rheology Stabilisation: The starch helps maintain optimal viscosity, yield point, and gel strength under downhole conditions, improving cuttings suspension and hole cleaning.

Adhesives & Industrial Binders:

• Biodegradable Adhesives: As a renewable, biodegradable polymer, oxidized starch is used as a base for environmentally friendly adhesives, including laminating adhesives, paper bag adhesives, wallpaper pastes, envelope glues, food packaging adhesives, and masking tape glue. Good film‑forming property and strong adhesive force make it effective in adhesive applications.
• Corrugated Board Adhesives: Oxidized starch functions as a binder in corrugated board adhesives and carton sealing glues. The paste liquid has strong cohesive force and high stability.

Construction & Building Materials:

• Gypsum Board and Wall Putties: Oxidized starch is used as a binder in gypsum board formulations, wall putties, and dry‑mix mortar formulations, improving workability, adhesion, and water retention.
• Construction Adhesives: Construction adhesives incorporate oxidized starch as a binder to control rheology and improve adhesion to mineral substrates.

Other Industrial Applications:

• Water Treatment: The starch functions as a flocculant and coagulant aid in industrial wastewater treatment and sludge dewatering operations.
• Agrochemicals: E1404 is used as a binder, thickener, and suspending agent in pesticide and fertiliser formulations.
• Biodegradable Films & Packaging: The film‑forming properties of oxidized starch are exploited in the production of biodegradable food packaging films, edible coatings for fruits and vegetables, and disposable cutlery.
• Cosmetics and Personal Care: Oxidized starch is widely used in skin cleansers, antiperspirants, roll‑on deodorants, lip balms, blushes, depilatories, baby powder, skin deodorants (for feet), carpet cleaners, liquid gloves, skin protective ointments, luminescent coatings, and other personal care products. It functions as a thickening agent, bulking agent, viscosity controller, and film former.
• Pharmaceuticals: The product can also be applied in medicine as a tablet binder, disintegrant, and filler.
• Fine Chemicals: Oxidized starch is applied in a range of fine chemical formulations including coatings, adhesives, and specialty chemical products.

3. Preparation Method:

• Laboratory Method: Oxidized starch can be synthesised in the laboratory by suspending native starch (from corn, potato, tapioca, or wheat) in water to form a slurry. The slurry is heated to 30–40°C, and the pH is adjusted to 8–9 with sodium hydroxide. Sodium hypochlorite (NaOCl) solution is added slowly with stirring, and the reaction is allowed to proceed for 1–3 hours. The degree of oxidation is controlled by the amount of hypochlorite added (typically 1–5% active chlorine based on starch weight), reaction temperature, pH, and duration. After the desired degree of oxidation is reached, the reaction is terminated by neutralisation with dilute hydrochloric acid or by the addition of sodium bisulfite to reduce excess hypochlorite. The product is washed repeatedly with water, filtered, dried at 50–60°C, and milled to the desired particle size.
• Industrial Process: Industrial production of high‑quality oxidized starch (E1404) follows a large‑scale alkaline hypochlorite oxidation process:
  1. Slurry Preparation: Native starch (from corn, waxy maize, tapioca/cassava, potato, or wheat) is slurried in water at a concentration of 35–40% solids with stirring.
  2. pH Adjustment: Sodium hydroxide is added to adjust the pH to 8–10 to create the alkaline conditions required for efficient oxidation.
  3. Oxidation: Sodium hypochlorite solution (NaOCl) is slowly added to the starch slurry at a controlled temperature (21–38°C) under constant agitation for 1–3 hours. The hypochlorite oxidises the primary alcohol groups at the C‑6 position and secondary hydroxyl groups at C‑2 and C‑3 of the glucose units, forming carbonyl and carboxyl groups. The degree of oxidation is precisely controlled by the NaOCl concentration, temperature, pH, and reaction time.
  4. Termination: After the desired carboxyl content is achieved, the reaction is terminated by adjusting the pH to 5–7 with dilute hydrochloric acid or by adding sodium bisulfite to neutralise residual hypochlorite.
  5. Purification (Washing): The crude oxidized starch is washed repeatedly with water to remove sodium chloride, sodium sulfate, soluble byproducts, and unreacted chemicals, followed by filtration or centrifugation.
  6. Optional Bleaching: The product may be bleached with hydrogen peroxide or sodium hypochlorite to improve whiteness.
  7. Drying: The purified wet starch cake is dried in flash dryers, rotary dryers, or fluidised bed dryers to a moisture content of ≤14% (cereal starch), ≤18% (other starches), or ≤21% (potato starch).
  8. Milling & Sieving: The dried product is milled to break up agglomerates and sieved to the desired particle size distribution (typically 80–200 mesh). For pregelatinised grades, the product is cooked, dried, and milled to produce flakes, amorphous powder, or coarse particles that dissolve instantly in cold water.
  9. Blending & Quality Control: Batches are blended for consistency. Key quality parameters include carboxyl group content (≤1.1 g/100g, by titration), loss on drying (≤14–21%), pH (4.5–7.5), viscosity (by Brabender or Brookfield), ash (≤0.5%), whiteness (≥83–90%), particle size (≥90% passing 0.18 mm), sulfur dioxide (≤30 mg/kg), heavy metals (Pb ≤1–2 mg/kg, As ≤1 mg/kg, Hg ≤0.1 mg/kg), and microbiological limits (TAMC, TYMC, pathogens).
  10. Packaging: The finished product is packaged in 25 kg multi‑wall moisture‑proof bags with polyethylene liners, 500–1000 kg FIBC (jumbo bags), or bulk containers for shipment. Custom packaging options are available for food‑grade, paper‑grade, and oilfield‑grade specifications.

4. Safety Information:

• Hazard Classification: Under GHS/CLP Regulation (EC) No 1272/2008, oxidized starch is generally classified as a non‑hazardous or very low hazard product. The substance is not classified as dangerous for transport under most regulatory schemes (UN number not assigned). However, high dust concentrations may carry hazard statement H335 (May cause respiratory irritation). The product is combustible and starch dust may form explosive mixtures with air. Minimum explosive limit of starch dust is approximately 40 g/m³. Health rating: 0 (None). Flammability rating: 2 (Slight). Explosive hazard: Starch dust forms an explosive mixture with air.
• Health Hazards:
  • Inhalation: Inhalation of airborne starch dust may cause mild respiratory tract irritation, coughing, or sneezing in sensitive individuals. Prolonged exposure to high dust concentrations may cause respiratory discomfort.
  • Skin Contact: Generally non‑irritating to intact skin. Prolonged or repeated contact may cause mild mechanical irritation or drying due to the abrasive effect of the powder.
  • Eye Contact: May cause mild mechanical irritation due to dust particles. Rinse with water.
  • Ingestion: Low acute oral toxicity (LD₅₀ > 5,000 mg/kg). The product is approved as a food additive (E1404) and is generally regarded as safe (GRAS) for human consumption. In vitro digestibility by pancreatin shows that oxidized starch is 10–15% less digestible than unmodified starch, but this difference does not translate into reduced caloric value or adverse health effects in vivo. Feeding studies in rats have shown that digestibility coefficients for oxidized starch are practically indistinguishable from those obtained for unmodified starch, with no tissue damage associated with consumption. Ingestion of large amounts may cause mild gastrointestinal discomfort (bloating, diarrhoea) due to its bulking effect.
• First Aid Measures:
  • Eye Contact: Rinse cautiously with plenty of water for several minutes. Remove contact lenses if present and easy to do. If eye irritation persists, seek medical attention.
  • Skin Contact: Wash skin with plenty of soap and water. Remove contaminated clothing. If skin irritation develops, seek medical advice.
  • Inhalation: Move person to fresh air. Keep at rest in a position comfortable for breathing. If symptoms (coughing, throat irritation) persist, seek medical advice.
  • Ingestion: Rinse mouth immediately. Do NOT induce vomiting. Drink water to dilute if conscious and able to swallow. Seek medical attention if a large amount is ingested or if symptoms develop.
• Personal Protective Equipment (PPE):
  • Respiratory protection: Use a dust mask (N95 or P2 respirator) if airborne dust concentrations are present or when handling powder grades in poorly ventilated areas.
  • Eye protection: Safety glasses or dust‑resistant safety goggles to prevent mechanical eye irritation from dust particles.
  • Skin protection: Protective gloves (nitrile or neoprene) and protective clothing to minimise skin contact and dust exposure.
  • General hygiene: Wash hands thoroughly after handling. Do not eat, drink, or smoke in work areas. Minimise dust generation and avoid breathing dust.
• Fire & Explosion Hazards: Oxidized starch is combustible and may burn if involved in a fire. Accumulated settled dust may form explosive concentrations in air when disturbed and dispersed, as with any organic dust. Minimum explosive limit (MEL) is approximately 40 g/m³. In case of fire, use water spray, foam, dry chemical powder, or CO₂ as extinguishing media. Thermal decomposition may produce irritating and toxic fumes including carbon monoxide (CO), carbon dioxide (CO₂), and low molecular weight organic compounds.
• Environmental Precautions: Oxidized starch is a biodegradable modified natural polymer derived from renewable starch sources. The substance is not classified as hazardous to the aquatic environment under current EU criteria. However, avoid large‑scale release into natural water bodies, drains, or soil. Comply with local environmental regulations for disposal.
• Storage & Stability: Store in tightly closed, moisture‑proof containers in a cool, dry, well‑ventilated area away from direct sunlight, heat sources, and strong oxidising agents. Oxidized starch is hygroscopic; exposure to atmospheric moisture leads to caking, lump formation, and reduced functional performance. Under recommended storage conditions (room temperature, low humidity, <30°C), the product has a shelf life of 24 months from the date of manufacture in sealed original containers. Upon opening, use the product as quickly as possible to prevent moisture regain.
• Regulatory Compliance: Oxidized starch (E1404, CAS#65996-62-5) is listed on EINECS (EC 269‑212‑0), TSCA, DSL, AICS, NZIoC, ENCS, KECI, and other regional chemical inventories.
  • US FDA Food Regulations: Oxidized starch is affirmed as GRAS (Generally Recognized as Safe) under 21 CFR §172.892 for use as a direct food additive. It is listed in the FDA’s Substances Added to Food (EAFUS) inventory and recognised as a food contact substance under 21 CFR.
  • EU Food Additive Status: Oxidized starch is authorised as a food additive under the designation E1404 pursuant to Regulation (EC) No 1333/2008 and meets the purity criteria set out in Commission Regulation (EU) No 231/2012. It is approved for use in food products across the European Union with no maximum usage level (quantum satis), subject to GMP.
  • JECFA (Joint FAO/WHO Expert Committee on Food Additives): Oxidized starch has an ADI (Acceptable Daily Intake) of “not specified” – the highest safety category indicating no safety concern at any level of intake – established at the 17th JECFA in 1973 and reaffirmed in subsequent evaluations.
  • China GB 2760: In China, oxidized starch is approved under GB 2760 as a food additive with CNS code 20.016 (for hydroxypropyl distarch phosphate) applicable to modified starches; oxidized starch may be used as a thickener in various food categories as needed, in accordance with GMP.
  • Kosher / Halal / Allergen‑Free: Kosher, Halal, non‑GMO, gluten‑free, and allergen‑free certifications are available for food and pharmaceutical grades upon request.
  • Oilfield Compliance: Oxidized starch used as a drilling fluid additive may be subject to local environmental regulations for offshore and onshore discharge.