| HS Code | 781974 |
| Chemical Name | Sodium Hydroxide |
| Chemical Formula | NaOH |
| Molecular Weight | 40.00 g/mol |
| Cas Number | 1310-73-2 |
| Purity | 99.9% |
| Physical Form | Solid beads |
| Color | White |
| Odor | Odorless |
| Solubility In Water | 111 g/100 mL at 20°C |
| Ph | 13.5 (1% aqueous solution) |
| Melting Point | 318°C |
| Boiling Point | 1388°C |
| Density | 2.13 g/cm³ at 25°C |
| Specific Gravity | 2.13 |
| Vapor Pressure | Negligible |
| Flash Point | Non-flammable |
As an accredited Sodium Hydroxide 99.9% Pure Food Grade Beads Caustic Soda factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in a sturdy, resealable food-grade container. Available quantity: 2 pounds of 99.9% pure sodium hydroxide beads for culinary use. |
| Container Loading (20′ FCL) | Sodium hydroxide beads packed in 25kg bags, palletized and loaded into a 20′ FCL container with secure, dry ventilation. |
| Shipping | This caustic soda ships in sealed, moisture-resistant bags or drums, clearly labeled with UN 1823 (Class 8). It must be transported via ground freight only, away from acids and moisture. Proper placarding, secure palletizing, and handling by trained personnel are required to ensure safe, compliant delivery. |
| Storage | Store in a sealed, clearly labeled container made of compatible materials like polyethylene or polypropylene. Keep in a cool, dry, well-ventilated area away from moisture, acids, and reactive metals. Protect from physical damage and contamination. Never store near food or water sources, as contact causes hazardous reactions. |
| Shelf Life | Shelf life is indefinite when stored tightly sealed in a cool, dry place, preventing moisture absorption and carbonation. |
Continuous caustic immersion peeling of clingstone peaches and round tomatoes is operated as a two-stage thermal-chemical separation rather than a fixed soaking step. Sodium hydroxide 99.9% food-grade beads are hydrated in a 316L stainless dissolution skid to an intermediate 50% w/w stock solution, then diluted to the working lye concentration with tempered water at 35–45°C. The applicable food-additive references are FDA 21 CFR 184.1763 for pH control and processing-aid use, the Food Chemicals Codex monograph for sodium hydroxide, EU Regulation (EU) No 231/2012 for additive E 524 purity, and 21 CFR 117 for cGMP execution on fruit and vegetable processing lines. In tomato peeling, the working bath is maintained at 8–12% w/w NaOH and 71–82°C, with immersion residence time of 30–60 s; cling peaches require 10–15% w/w NaOH at 82–93°C for 45–90 s because the pectinous flesh resists skin separation at lower alkalinity. Root vegetables such as potatoes are run at 8–12% w/w NaOH at 60–75°C for 2–6 min depending on tuber size and storage starch composition. The production sequence uses steam-jacketed lye troughs, recirculation manifolds, rotary drum washers, and citric acid neutralization sprays; peeling performance is monitored by residual skin patch count per 100 kg lot. Process control is narrow: a 2°C drop below the tomato line setpoint increases under-peeled fruit by visual defect count, while a 3°C rise above setpoint accelerates flesh softening and raises trim loss beyond 5–8% in cling peach lines. Terminal finished products include canned diced tomatoes, tomato paste, peach halves, frozen potato strips, and baby carrot pieces.
| Substrate | NaOH working concentration (% w/w) | Bath temperature (°C) | Residence time |
|---|---|---|---|
| Round tomato | 8–12 | 71–82 | 30–60 s |
| Cling peach | 10–15 | 82–93 | 45–90 s |
| Potato | 8–12 | 60–75 | 2–6 min |
Spanish-style green olives and California black-ripe olives are processed through lye hydrolysis of oleuropein rather than simple pH adjustment. Fermentation-grade lye is prepared from 99.9% bead sodium hydroxide to a working concentration of 2.0–4.5% w/v at 18–25°C; the immersion continues for 12–24 h until the lye front reaches 2/3 to 3/4 of the distance from skin to pit. Processing is performed in vertical stainless or fiberglass lye tanks with recirculation and aeration; after alkalinization, fruit is washed in 2–3 changes of potable water until residual lye is no longer detectable by phenolphthalein test, then brined at 5–8% w/v sodium chloride and fermented at 20–25°C by indigenous or inoculated lactic acid bacteria. The relevant standards are Codex STAN 66-1981 for table olives, FDA 21 CFR 184.1763, EU Regulation (EC) No 1333/2008 for use of E 524, and 21 CFR 117. Over-penetration of lye into the flesh causes soft product, internal splitting, and loss of firmness; under-penetration leaves bitter oleuropein and leads to fermentation failure. Terminal finished product types include Spanish-style green olives, pitted and sliced olives, California black-ripe olives, and olive paste.
Alkalized cocoa liquor is produced by adding 1.0–3.0% NaOH by mass of cleaned cocoa nibs as a 10–20% aqueous solution in a closed reactor, with moisture held at 15–25% on nib mass. The reaction is carried out at 90–110°C for 45–120 min under 1.5–2.5 bar absolute pressure, and the endpoint pH is maintained between 6.8 and 8.2. A pH above 8.2 shifts the flavor profile toward soapy, bitter fractions and darkens the powder excessively; a pH below 6.8 gives insufficient polyphenol solubilization and weak red-brown color development. After alkalization, the nibs are dried and roasted, then milled and pressed to separate cocoa butter from press cake. Compliance references include Codex STAN 141-1983 for cocoa powders, FDA 21 CFR 184.1763, and EU Regulation (EU) No 231/2012 for E 524. The production sequence uses jacketed ribbon or paddle reactors, vacuum drying, and pin milling; batch-to-batch variance in nib moisture is controlled by pre-drying before caustic addition. Terminal finished products include alkalized cocoa powder, dark chocolate liquor, cocoa butter, chocolate-flavored dairy beverages, and bakery coatings.
When soybean oil enters the short-mix neutralizer at a free fatty acid content of 0.18–0.35% w/w as oleic acid, the sodium hydroxide addition is calculated from acid value rather than fixed bead percentage. Free fatty acid content is determined according to ISO 660:2020 or AOCS Ca 5a-40, and the stoichiometric dry NaOH requirement is approximated as FFA (%) × 0.142; a process excess of 0.02–0.05% of oil mass is added to force the neutralization of phospholipids and trace metals. The caustic solution is prepared from 99.9% beads at 8–16% w/w NaOH (12–20°Bé) and injected after acid conditioning with 0.05–0.15% w/w of 75% phosphoric acid at 60–70°C for 15–30 min. The conditioned oil moves through an inline static mixer into a self-cleaning disk stack centrifuge, usually operating at 7,000–8,500 rpm, to separate hydrated gums and soapstock from neutralized oil; then the oil is water-washed, vacuum-dried, and bleached. Excess caustic above the process window saponifies neutral triglycerides and raises refining loss, while insufficient caustic leaves free fatty acids and residual phospholipids that produce cloudiness and poor oxidative stability. Compliance references for the finished oils are Codex STAN 210-1999, FDA 21 CFR 184.1763, and EU Regulation (EU) No 231/2012 for E 524. Terminal finished products include neutralized soybean, rapeseed, palm, and sunflower oils, margarine, shortening, and frying oils.
| Free fatty acid content (% w/w as oleic) | Theoretical NaOH requirement (% of oil mass) | Process excess (% of oil mass) | Caustic solution strength (°Bé / % w/w) |
|---|---|---|---|
| 0.10 | 0.014 | 0.02–0.05 | 12–20°Bé / 8–16% w/w |
| 0.25 | 0.036 | 0.02–0.05 | 12–20°Bé / 8–16% w/w |
| 0.50 | 0.071 | 0.02–0.05 | 12–20°Bé / 8–16% w/w |
| 1.00 | 0.142 | 0.02–0.05 | 12–20°Bé / 8–16% w/w |
Recirculating clean-in-place stations for dairy and beverage plants use 0.5–2.5 wt% sodium hydroxide at 60–85°C with contact time of 15–40 min and flow velocity of 1.5–2.5 m/s through 316L stainless steel piping. The caustic solution is dosed by conductivity at 5–25 mS/cm; if the plant room is unheated and the solution is stored at ambient temperature, the concentration must be checked against published freezing point data because 0.5–1.0 wt% sodium hydroxide freezes near 0°C, and only more concentrated stock solutions above approximately 5 wt% remain pumpable below -5°C. Water hardness above 200 ppm calcium carbonate is controlled by softening or sequestrant addition to prevent calcium carbonate scale from masking stainless surfaces. The relevant standards include FDA 21 CFR 117, 3-A Sanitary Standards 00-01, EHEDG Doc 4, and ISO 14159:2002 for hygiene requirements. The CIP sequence removes proteinaceous and fatty soil after a pre-rinse, then sanitizes with peracetic acid or hot water. Terminal finished product types include pasteurized milk, milk powder precursors, beer, carbonated soft drinks, and processed cheese.
In corn wet milling and high-fructose corn syrup production, sodium hydroxide 99.9% beads are dissolved to a 5–10% w/w solution and added after acid or enzyme hydrolysis to raise the pH of clarified starch hydrolysate from approximately 4.0–4.5 to 5.5–6.5 before glucose isomerase exposure. The addition ratio is held at 0.01–0.1% w/w on dry starch basis; above this range the subsequent ion exchange deashing load increases, and below this range residual acid reduces isomerase productivity. pH-adjusted hydrolysate is passed through cation and anion exchange columns, carbon-refined, and evaporated to syrup. The same food-grade caustic is used for resin regeneration. Compliance references are FDA 21 CFR 184.1763, Codex STAN 192-1995 General Standard for Food Additives, and EU Regulation (EU) No 231/2012 for E 524. Terminal finished product types include glucose syrup, high-fructose corn syrup, caramel color, and dextrose monohydrate.
Competitive Sodium Hydroxide 99.9% Pure Food Grade Beads Caustic Soda prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@liwei-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@liwei-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Sodium Hydroxide 99.9% Pure Food Grade Beads Caustic Soda is anhydrous sodium hydroxide supplied as free-flowing spherical beads and certified for food-additive and food-processing use under E 524 in Regulation (EU) No 231/2012 and under the sodium hydroxide monograph of the Food Chemicals Codex. The compound carries CAS 1310-73-2, molecular formula NaOH, and molar mass 39.997 g/mol. Manufacturer-specific model coding such as NaOH-FG99.9-BD may be assigned to the bead morphology and food-grade certification, but procurement documentation should always reference CAS 1310-73-2 and the applicable food-additive monograph because model strings are not harmonized across suppliers. Certificate-of-analysis data for the 99.9% grade typically report assay at ≥99.9% w/w NaOH on a dry basis, sodium carbonate below 1.0% w/w as Na₂CO₃, and controlled levels of lead, mercury, arsenic, chloride, and iron. The material is hygroscopic and carbon dioxide–absorptive; unsealed exposure produces surface water uptake and sodium carbonate formation.
The bead form differs from flake and pellet forms in particle geometry, dusting behaviour, feeding characteristics, and dissolution surface area. These differences become material when the product is metered through automatic dosing skids or stored in bulk silos. The product is intended for applications where food-grade impurity control is required, not merely high alkali strength. Residual sodium hydroxide and heavy-metal contaminants are regulated in final food and food-contact operations, and the food-grade certification provides the relevant monograph limits.
Technical caustic soda is often supplied as flake, pellet, prill, bead, or 50% liquid. The food-grade bead product differs from technical flakes and pellets primarily in impurity ceilings, food-additive monograph testing, and particle morphology. Flake material has higher surface area per unit mass and dissolves more rapidly, but irregular flake edges generate airborne dust during drum charging and hopper transfer. Beads reduce dusting and provide more uniform flow through loss-in-weight feeders. Technical flakes and pellets may contain higher chloride, iron, and heavy-metal residues and are not routinely certified to FCC or E 524 limits. Bead bulk density and nominal particle size must be matched to the dissolving and conveying equipment. Representative values are summarised below.
| Parameter | Food Grade Beads | Technical Flakes | Technical Pellets |
|---|---|---|---|
| Assay as NaOH | ≥99.9% w/w dry basis | 97.0–99.0% w/w typical | 98.0–99.0% w/w typical |
| Nominal particle size | 0.8–2.0 mm bead diameter | Irregular flakes 0.5–5.0 mm, thickness 0.5–1.5 mm | 2.0–4.0 mm pellet diameter |
| Bulk density | 0.9–1.1 kg/L | 0.7–0.9 kg/L | 1.0–1.2 kg/L |
| Food-additive monograph | FCC, E 524 | Not typically certified | Not typically certified |
| Heavy metal testing | Pb ≤2 mg/kg, Hg ≤1 mg/kg, As ≤3 mg/kg | Not necessarily tested | Not necessarily tested |
| Dust generation in hopper charging | Low due to spherical bead morphology | High due to irregular edges | Low due to low surface area |
For a target pH adjustment, sodium hydroxide also differs from potassium hydroxide on an equivalent-weight basis. NaOH has an equivalent weight of 39.997 g/eq, while KOH has an equivalent weight of 56.106 g/eq. Therefore, a lower mass of NaOH is required to deliver the same stoichiometric hydroxide alkalinity. This is relevant when sodium content is permissible and potassium salts are not required in the process stream.
The food-additive specification for sodium hydroxide E 524 in Regulation (EU) No 231/2012 requires total alkali not less than 98.0% w/w NaOH and sodium carbonate not more than 1.0% w/w. The Food Chemicals Codex sodium hydroxide monograph specifies an assay range of 95.0–100.5% w/w NaOH and separate ceilings for arsenic, lead, and mercury. A product labelled 99.9% pure therefore exceeds the minimum assay requirement and is selected when low carbonate and low impurity concentrations are required. Because assay and carbonate are measured on a dry basis at the time of packaging, the certificate of analysis cannot be extrapolated after the package has been exposed to humid air or carbon dioxide. Sodium carbonate accumulation changes buffering behaviour and can affect turbidity in prepared solutions.
| Parameter | Specification | Reference method or monograph |
|---|---|---|
| Assay as NaOH | ≥99.9% w/w dry basis | FCC sodium hydroxide monograph, ISO 979 |
| Sodium carbonate as Na₂CO₃ | COA typical ≤0.5% w/w; E 524 limit ≤1.0% w/w | ISO 3196 |
| Arsenic | ≤3 mg/kg | FCC, E 524 |
| Lead | ≤2 mg/kg | FCC, E 524 |
| Mercury | ≤1 mg/kg | FCC, E 524 |
| Chloride as NaCl | COA typical ≤100 mg/kg | ISO 981 |
| Iron as Fe | COA typical ≤10 mg/kg | ISO 983 |
| Particle size | 0.8–2.0 mm or 1.0–2.0 mm supplier COA | Sieve analysis, supplier procedure |
Particle size distribution is not defined in the food-additive monograph; it is supplier-controlled and must be confirmed against the dissolving and transfer equipment. Sodium carbonate specification is particularly important where rapid pH adjustment and low solution turbidity are required, because carbonate can buffer the solution and alter the titration curve.
In lye peeling applications, the bead product is dissolved to a working concentration of 1.0–5.0% w/w NaOH and held at 60–95 °C in a jacketed 316L stainless steel bath. Residence time is set between 1 min and 10 min according to fruit or vegetable epidermis thickness; downstream brush washers and rotary drum washers reduce surface pH to below 8.0 before acid blanching. For pretzel gelatinization, a separate bath with 0.75–1.0% w/w NaOH at 80–90 °C uses immersion times of 5–15 s; the alkaline surface is converted during baking and surface gloss is controlled by bath concentration and temperature. In cocoa alkalization, sodium hydroxide is added as a 20–25% w/w stock solution to control alkalinity during Dutching; addition is based on 0.5–2.0% w/w alkali on nib mass, with the final endpoint determined by liquor pH and pressing behaviour. In returnable glass bottle washing, caustic solutions prepared from food-grade beads are operated at 1.5–3.0% w/w NaOH and 60–85 °C for label removal; excursions above 3.0% at 85 °C can produce measurable glass surface attack over repeated cycles.
The heat of solution of NaOH in water is approximately −44.5 kJ/mol; preparation of a 10% w/w solution from 50 kg beads and 450 L water can raise the bulk temperature by more than 35 °C under adiabatic conditions. Automatic dosing skids must therefore add beads into agitated water at a rate that keeps the bulk temperature below the continuous-use rating of the mixing tank, commonly 60 °C for HDPE and PP vessels. Agitation must be sufficient to prevent high-concentration zones at the liquid surface; an eductor or recirculation loop with a 316L stainless steel centrifugal pump is used to feed beads or concentrated stock solution into the discharge stream. Water must never be added to a charge of concentrated solid NaOH; the resulting local boiling and spatter risk is severe.
In hopper-fed dosing, the discharge cone should have an angle greater than 70° from horizontal and an outlet diameter at least 6 times the maximum bead diameter of 2.0 mm to reduce cohesive arching. Loss-in-weight feeding is preferred where mass-based addition is required. Stock solutions stored at 25 wt% NaOH remain pumpable at 20 °C; 50 wt% NaOH can solidify at temperatures below approximately 12 °C and requires heat tracing. Viscosity at 20 °C increases from approximately 18 mPa·s at 25 wt% to approximately 78 mPa·s at 50 wt%, which must be accounted for in pump sizing and line pressure drop.
Beads with nominal diameter 0.8–2.0 mm are transferred by vacuum or low-pressure dilute-phase pneumatic conveying. Conveying velocities above 25 m/s increase particle attrition and generate fines that reduce flowability and increase dust formation. Storage silos and hoppers should be constructed from 304L stainless steel, 316L stainless steel, HDPE, PP, or lined carbon steel. Aluminium, galvanized steel, zinc, brass, and bronze are incompatible because NaOH attacks these materials with hydrogen evolution. The storage headspace should be maintained below 40% RH at 20 °C using dry-air purge or a desiccant breather; the purge air should be low in carbon dioxide to reduce sodium carbonate crust formation. If a nitrogen blanket is used, residual oxygen below 1% v/v and carbon dioxide below 100 ppm v/v are typical targets for long-term stock. Bulk bags must be resealed immediately after sampling; partial bags exposed to humid air can develop surface fusion and lumps that obstruct feeders.
Field behaviour on production-scale bulk handling systems shows that bead material can form a cohesive arch when moisture uptake exceeds 0.5% w/w, particularly if the hopper throat is smaller than 12 mm or the cone angle is shallow. Vibration-assisted discharge is applied only when the hopper is designed for vibrating service; prolonged vibration compacts the bead bed and can worsen flow stoppage.
Sodium hydroxide is incompatible with strong acids, aluminium, magnesium, zinc, tin, and galvanized surfaces. Mixing with concentrated acid generates substantial heat and can produce violent boiling in enclosed dosing lines. Ammonium salts release ammonia when heated with NaOH. Sodium hydroxide/hypochlorite cleaning mixtures must never be acidified, because chlorine gas is liberated at reduced pH. In food-contact cleaning systems, the alkaline stage must be followed by an intermediate rinse before acid cleaning to prevent aggressive neutralization reactions inside the circuit.
For clean-in-place circuits in dairy, beverage, and food processing, caustic solutions prepared from food-grade beads are typically run at 1.0–2.5% w/w NaOH and 65–80 °C for 15–30 min; validation depends on soil type, spray-ball coverage, turbulence, and return-flow temperature. Above 80 °C, 316L stainless steel in continuous hot 50% caustic service can become susceptible to caustic stress corrosion cracking; high-nickel alloys or lined carbon steel are specified for those conditions. Plate heat exchangers must be evaluated for localized skin temperatures, because heating surfaces can exceed the bulk set point. Lye peeling lines are stopped when the caustic bath accumulates fruit skins and dissolved pectin; the bath is filtered or replenished based on measured free alkalinity rather than simple pH. The final rinse stage is monitored by pH, and food-contact surfaces are returned to neutral before production resumes.
In the United States, sodium hydroxide is affirmed as GRAS under 21 CFR 184.1763. In the European Union, sodium hydroxide used in food processing is subject to Regulation (EC) No 1333/2008 and Regulation (EU) No 231/2012; final residues are governed by food-contact material legislation and national food law. The operational boundary is defined by the interaction of temperature, concentration, contact time, and equipment metallurgy rather than by the purity label alone.
Committed to quality, innovation, and reliable chemical solutions for a sustainable future.
