E466 CMC

E466 CMC (sodium carboxymethyl cellulose, cellulose gum) is a cellulose ether with a negative charge, high molecular weight and good solubility in water. It is obtained by attaching carboxymethyl groups (-CH₂-COOH) to some of the hydroxyl groups of the glucopyranose units that make up the cellulose chain, and it is sold in the form of its sodium salt for use as a thickener, stabilizer, emulsifier, binder, water-retention agent, film former and suspending agent in the food, pharmaceutical, cosmetic and industrial sectors.
E466 CMC offers thickening, stabilizing, water-holding, suspending, emulsifying and film-forming performance in a single polymer; in water it gives a transparent colloidal solution that stays stable over time, and as a safe, biodegradable material of plant origin it is used throughout food, household chemicals, pharmaceuticals, oil drilling and papermaking.
E466 CMC was first prepared by the German chemist Erich Jansen in 1918 and the process was patented in 1921; since then it has grown into one of the most important and most widely applied hydrocolloids in the world, together with xanthan gum.

CAS Number: 9004-32-4
EC Number (ECHA): 100.120.377
Molecular Formula: [C₆H₇O₂(OH)x(OCH₂COONa)y]n 

Synonyms: Sodium Carboxymethyl Cellulose, Carboxymethyl Cellulose, CMC, NaCMC, SCMC, Sodium CMC, Cellulose Gum, Carmellose, Carboxymethylcellulose Sodium, Carboxy Methyl Cellulose, Sodium Carboxymethylcellulose, Cellulose Carboxymethyl Ether, CMC Gum, Sodium Cellulose Glycolate, Tylose, Celluvisc, Carmellose Sodium, E466, INS 466, CAS 9004-32-4

E466 CMC stands out among hydrocolloids for its flexibility: at very low dosage it can reshape the texture, viscosity and stability of a finished product.
E466 CMC is available as a white to off-white powder that flows freely and disperses easily in water, and each application can be served by picking the viscosity grade and degree of substitution that fit it best.

E466 CMC acts by binding water and building a network of hydrated polymer chains, which holds particles in suspension, delays phase separation and gives products an even, smooth body.
E466 CMC is derived from plant material and has neither smell nor taste, which lets formulators add it without any change to flavor, color or aroma.
E466 CMC is compatible with most ingredients found in typical formulations, apart from strong acids and high levels of multivalent cations, making it a dependable and economical option for producers in many industries.

E466 CMC is the partial sodium salt of a carboxymethyl ether of cellulose: some hydroxyl groups on the β-1,4-linked D-glucose units of the cellulose chain are replaced with carboxymethyl groups (-OCH₂COO⁻Na⁺), which produces an ionic, negatively charged polymer that dissolves well in water, builds high viscosity at low concentration and shows a broad range of flow behavior depending on the degree of substitution (DS) and degree of polymerization (DP).
E466 CMC differs from the non-ionic methyl cellulose (E461) in being an anionic polysaccharide, with carboxylate groups that are negatively charged in water; this charge makes E466 CMC bind well to milk proteins and other proteins and form complexes that thicken the system without greatly altering its shear or flow behavior.

E466 CMC for food use normally has a DS of 0.4 to 1.5; at a DS below 0.3 the product dissolves only in alkali, above 0.4 it becomes water-soluble, around 0.7 it gives the grades that dissolve most readily, and above 1.5 it shows better stability in acidic and alkaline media because more of the reactive hydroxyl groups have been substituted.
E466 CMC passes through the human body without being metabolized and is eliminated nearly unchanged in the feces, so it adds no calories at normal use levels; the US FDA lists it as GRAS and JECFA (FAO/WHO) has set an ADI of 0–25 mg/kg body weight, which confirms its safety in food.

Uses of E466 CMC:
E466 CMC serves in soymilk as a suspending, emulsifying and stabilizing agent that blends into the base mixture, keeping fat from rising and protein from settling, while also helping to whiten the milk, soften its taste and reduce the beany odor.
E466 CMC thickens instant paste-type foods such as peanut, sesame and almond paste, letting them dissolve evenly in cool water and turn out smooth, fine and aromatic, while also making artificial sweeteners taste better and giving more stability than starch pastes.

E466 CMC serves in condiments such as peanut butter, chili sauce, jam and oyster sauce in specially modified grades that tolerate salts and acids, improving the structure of these products, making them thicker and more stable, and enhancing their color, aroma and flavor.
E466 CMC limits how ice crystals form and grow in ice cream and frozen desserts during freezing and storage, which gives a creamier, smoother texture, higher overrun and steadier emulsions, and prevents syneresis and separation of ingredients.

E466 CMC serves in bakery products (bread, cakes, pastries, muffins, gluten-free goods) to hold moisture, delay staling, strengthen dough elasticity and volume, produce a finer and softer crumb, ease demolding, and imitate certain properties of gluten in gluten-free recipes.
E466 CMC improves mouthfeel and suspension in drinks such as fruit juices, soft drinks, dairy drinks, plant-based milks and protein beverages, keeps particles from settling, creates a stable cloud in juice beverages and helps instant drink mixes disperse.

E466 CMC serves in sauces, dressings, ketchups, gravies and other condiments as an effective thickener and emulsion stabilizer that gives an even, smooth texture, keeps spices and solid pieces evenly distributed, prevents oil and water from separating and makes low-fat or reduced-calorie versions possible.
E466 CMC binds and stabilizes processed meats and plant-based meat products (sausages, hot dogs, meatballs, meat analogues), raising water-holding capacity, giving consistent texture and shape, cutting cooking loss and adding juiciness and tenderness.

E466 CMC serves in dairy products (yogurt, cottage cheese, cheese, dairy desserts) as a thickener, stabilizer and texturizer that keeps ingredients from separating, improves mouthfeel and prevents syneresis; it also blocks unwanted crystallization, which matters for keeping the texture of these products intact.
E466 CMC adjusts texture in confectionery (candies, chewing gum, jellies, marzipan, sugar pastes), stops moisture migration and sugar crystallization, adds elasticity, and works as an edible coating film for sweets and as a food adhesive and clear glaze for fresh-fruit decorations.

E466 CMC serves in toothpaste as the main thickener, allowing liquid and solid raw materials to blend fully and giving suitable viscosity, gloss, smoothness, shapeability and flow; it also acts as a stabilizer in shampoos, conditioners, face masks, skin creams and sunscreens.
E466 CMC is a tablet binder, film-coating agent, suspending agent for liquid medicines and controlled-release matrix for capsules in pharmaceuticals, and it is also found in artificial tears and eye drops for dry eye.

E466 CMC serves in oil drilling as a drilling-mud additive that adjusts viscosity, retains water, protects the borehole wall and reduces fluid loss, and it is also used in fracturing fluids to carry solid fillers into wells.
E466 CMC functions in laundry detergents as an anti-redeposition polymer; it settles onto cotton and other cellulosic fabrics and forms a negatively charged barrier that keeps washed-out soil from returning to the cloth.

E466 CMC serves in textiles as a thickener in printing pastes (2–3%), a finishing agent, a binder for nonwovens and a yarn sizing agent (1–3%); in papermaking it works as a sizing agent, strengthening agent and dispersant that improves surface strength, smoothness and printability.
E466 CMC improves water retention, workability and adhesion in cement and mortar additives for concrete mixes, raises viscosity and prevents sagging in paints and coatings for easy application, and keeps flow and bond strength steady in adhesives.

E466 CMC serves in lithium-ion battery production as an electrode binder for graphite anodes; it can be processed from water, avoiding the toxic solvent n-methylpyrrolidone (NMP) that conventional PVDF binders require, and it is often combined with styrene-butadiene rubber (SBR) for silicon-containing anodes that need extra flexibility.
E466 CMC is employed in research and biotechnology as a substrate for endoglucanase assays, a binder for cation-exchange resins in ion-exchange protein purification, a dispersant for carbon nanotubes in water and, in ice packs, a component of a low-freezing eutectic mixture.

Benefits or Advantages of E466 CMC:
E466 CMC can take the place of food gums such as gelatin, agar, sodium alginate, guar gum and pectin, lowering production costs, raising product quality, improving taste and extending shelf life, which makes it a popular additive in powdered and liquid drinks, canned foods, candy, cakes, instant noodles, ready meals, soymilk and fruit juice.
E466 CMC thickens strongly even at very low dosage, producing smooth and stable viscosity in liquids with far less material than starch, agar or gelatin, so formulations can be economical and viscosity precisely controlled.

E466 CMC holds water very well: it keeps moisture in, improves texture and prevents drying out or syneresis in foods; it limits dehydration and shrinkage to prolong shelf life; and it gives freeze-thaw stability by controlling ice crystal formation in frozen desserts.
E466 CMC withstands salts and alkali, so it can stand in for guar gum in high-electrolyte systems such as salty condiments and acid-stable sauces, and it keeps viscosity and stability over a wide pH range (optimum 6.5–9.0) together with many different food ingredients.

E466 CMC is non-toxic, is not allergenic in the great majority of people and has been judged safe for human consumption by the FDA, EFSA, JECFA and regulators around the world; extensive toxicological data show no carcinogenic, mutagenic, teratogenic or reproductive effects.
E466 CMC is made from plant cellulose (cotton linters or wood pulp) without any animal material, which makes it vegan, gluten-free, halal and kosher and suitable for all major dietary and religious requirements.

Features of E466 CMC:
E466 CMC is a slightly hygroscopic, odorless and tasteless powder or fibrous flake that ranges from white to off-white (cream), gives a clear to slightly opalescent viscous colloidal solution in both cold and hot water, and does not dissolve in methanol, ethanol, acetone, chloroform or benzene.
E466 CMC gives a viscosity of 25–50,000 mPa·s in 1% aqueous solution depending on grade; the viscosity is at its peak between pH 6.5 and 9.0, begins to drop under pH 6, gels under pH 2.5, and also declines above pH 9, more quickly beyond pH 11.5.

E466 CMC loses viscosity as temperature rises (reversibly in the low to moderate range) but suffers permanent viscosity loss beyond a critical temperature; inorganic salts raise viscosity, and a higher DS makes viscosity less sensitive to temperature.
E466 CMC comes in technical grade (about 60% CMC plus about 40% sodium chloride and sodium glycolate, used in detergents), semi-purified grade (used in paper) and pure food/pharmaceutical grade (salts removed), each with its own purity level and range of uses.

Chemical Properties of E466 CMC:
E466 CMC is built from anhydroglucose units joined by β-1,4-glycosidic bonds, with carboxymethyl groups (-OCH₂COO⁻Na⁺) scattered randomly along the cellulose chain; its general formula is [C₆H₇O₂(OH)x(OCH₂COONa)y]n with x + y = 3.0, and the DS (y) for food grade lies between 0.20 and 1.50.
E466 CMC is prepared by an alkali-catalyzed reaction of cellulose with chloroacetic acid (or sodium monochloroacetate), which attaches polar carboxyl groups and makes the cellulose water-soluble and chemically reactive: Cell-OH + NaOH → Cell·O⁻Na⁺ + H₂O; then Cell·O⁻Na⁺ + ClCH₂COO⁻Na⁺ → Cell-OCH₂COO⁻Na⁺ + NaCl.

E466 CMC is fairly stable over a wide pH range and resists degradation by strong light; it does not dissolve in vegetable or animal fats, and it is incompatible with concentrated strong acids (which precipitate the free acid form), certain metal cations (Ca²⁺ and Fe³⁺ can cross-link CMC and make it gel) and strong oxidizing agents.
E466 CMC can replace guar gum, gelatin, agar, sodium alginate and pectin in many food and industrial applications as a green, safe, biodegradable functional polymer, with its properties set by DS, degree of polymerization (DP), solution concentration, pH, temperature and electrolytes.

Production of E466 CMC:
E466 CMC is manufactured from purified cellulose (cotton linters or softwood pulp) in two stages: alkalization, in which the cellulose is treated with aqueous NaOH (5–50%) to give alkali cellulose, and etherification, in which the alkali cellulose reacts with sodium monochloroacetate (up to 30%) in an alcohol-water medium at 50–75°C with controlled stirring until the target DS is reached.
E466 CMC leaves the process at first as roughly 60% CMC and 40% salts (sodium chloride and sodium glycolate); another purification step strips out those salts to give pure CMC for food and pharmaceutical use, and a semi-purified intermediate grade retains some salt for paper.

E466 CMC quality is controlled by the ratio of reactants, temperature, reaction time and the use of organic solvents (for example isopropanol) during etherification, all of which determine DS, DP, molecular weight, viscosity grade and solubility behavior.
E466 CMC is sold by leading producers worldwide in food grade (FCC), pharmaceutical grade (USP/NF/EP) and industrial/technical grade, in low (25–100 mPa·s), medium (100–5,000 mPa·s) and high (5,000–50,000 mPa·s) viscosity classes at 1% in water, with uniform particle size, neutral taste and no odor.

Stability and Reactivity of E466 CMC:

Chemical stability:
E466 CMC is stable under normal storage conditions when kept in sealed containers at ambient temperature and protected from moisture.

Reactivity:
E466 CMC is not expected to react dangerously under normal conditions of use.
E466 CMC may gel or precipitate in the presence of concentrated divalent or trivalent cations (Ca²⁺, Fe³⁺) and may lose viscosity at extreme pH (<2 or >12) or high temperature.

Conditions to avoid:
E466 CMC should be kept away from high concentrations of divalent cations (calcium, magnesium, iron).
E466 CMC should not be exposed to extreme pH below 2 or above 12.

E466 CMC should not be held at high temperature for long periods (permanent viscosity loss).
E466 CMC should be protected from moisture in storage (hygroscopic; may cake).

Incompatible materials:
E466 CMC is incompatible with concentrated strong acids (precipitate the free acid form).
E466 CMC is incompatible with strong oxidizing agents.
E466 CMC is incompatible with high concentrations of calcium, iron and other multivalent cations.

Hazardous decomposition products:
E466 CMC may release carbon monoxide (CO).
E466 CMC may release carbon dioxide (CO2).
E466 CMC may release acrid smoke and irritating organic fumes (on high-temperature decomposition or in a fire).

Handling and Storage of E466 CMC:

Handling:
E466 CMC should be handled according to good industrial hygiene and safety practice.
E466 CMC dust should not be inhaled; use respiratory protection where dust cannot be avoided.

E466 CMC handling calls for eye protection wherever dust may form.
E466 CMC handling should be followed by thorough hand washing.
E466 CMC should be pre-mixed with dry ingredients before being added to liquid systems to avoid lumps.

Storage:
E466 CMC should be stored at ambient temperature in a cool, dry, well-ventilated place.
E466 CMC should be kept in tightly closed original containers, since it is slightly hygroscopic and can absorb moisture and cake.
E466 CMC remains stable under the recommended storage conditions.

First Aid Measures of E466 CMC:

Inhalation:
After inhalation of E466 CMC dust, move the person into fresh air.
E466 CMC dust may cause mechanical irritation of the airways; obtain medical advice if symptoms continue.

Skin contact:
After skin contact with E466 CMC, wash the area with soap and water.
E466 CMC has rarely been linked to severe allergic reactions; obtain medical help immediately if hives, itching, swelling or other allergic symptoms appear.

Eye contact:
After eye contact with E466 CMC, rinse at once with plenty of clean water for at least 15 minutes.
E466 CMC eye exposure needs medical attention if irritation does not subside.

Ingestion:
E466 CMC is practically non-toxic at food-use levels and is excreted unchanged without being metabolized.
After ingestion of E466 CMC, rinse the mouth with water and drink plenty of water.
E466 CMC taken in large quantities, or followed by gastrointestinal discomfort, calls for medical advice.

Firefighting Measures of E466 CMC:

Suitable extinguishing media:
E466 CMC fires can be fought with water spray, foam, dry chemical powder or carbon dioxide.

Specific hazards:
E466 CMC is combustible when in dry powder form.
E466 CMC gives off acrid smoke and irritating organic fumes when it decomposes thermally.

Protective equipment for firefighters:
E466 CMC fires require firefighters to wear self-contained breathing apparatus (SCBA) and full protective clothing.

Firefighting instructions:
E466 CMC containers exposed to fire should be cooled with water spray.
E466 CMC firefighting run-off should be prevented from reaching drains or waterways.

Accidental Release Measures of E466 CMC:

Personal precautions:
E466 CMC dust should not be inhaled; wear suitable respiratory protection.
E466 CMC powder becomes slippery when wet; contain and absorb spills immediately.

Environmental precautions:
E466 CMC is biodegradable and of low environmental concern; keep large amounts out of drains and waterways.

Methods for cleaning up:
E466 CMC dry spills should be swept or vacuumed into labeled waste containers, avoiding dust formation.
E466 CMC waste should be disposed of according to local regulations.

Exposure Controls / Personal Protective Equipment of E466 CMC:

Engineering controls:
E466 CMC operations that raise dust during weighing, mixing or bagging should have adequate local exhaust ventilation.

Eye protection:
E466 CMC handling should be done with safety glasses or goggles where dust may form.

Hand protection:
E466 CMC handling over long periods calls for gloves.

Respiratory protection:
E466 CMC dust that cannot be avoided calls for a NIOSH-approved dust respirator.

Hygiene measures:
E466 CMC handling should be followed by thorough hand washing, and always before eating, drinking or smoking.

Identifiers of E466 CMC:
E Number: E466 (standard); E469 (enzymatically hydrolyzed)
CAS Number: 9004-32-4
EC Number (ECHA): 100.120.377
HS Code: 39123100
Chemical Name: Sodium carboxymethyl cellulose; Cellulose gum
Molecular Formula: [C₆H₇O₂(OH)x(OCH₂COONa)y]n
ChEBI: CHEBI:85146
ChEMBL: ChEMBL1909054
UNII: 05JZI7B19X
CompTox (EPA): DTXSID7040441
JECFA ADI: 0–25 mg/kg body weight/day
US FDA: GRAS; food additive and food contact substance
EU: Approved food additive E466 under Regulation (EC) No 1333/2008; specifications in Commission Regulation (EU) No 231/2012
GHS Classification: Not classified as hazardous
Halal: Yes
Kosher: Yes
Vegan: Yes
Gluten-free: Yes
Ionic character: Anionic

Properties of E466 CMC:
Physical state: Solid (powder or fibrous flakes)
Appearance: Slightly hygroscopic, white to off-white (cream), odorless and tasteless granular or fibrous powder
Odor: Odorless
Taste: Tasteless
Molecular weight: >17,000 Da (varies; depends on grade; DP ≥100)
Degree of substitution (DS): 0.20–1.50 (food grade: 0.4–1.5)
Viscosity (1% aqueous solution): 25–50,000 mPa·s (depends on grade)
Optimal viscosity pH: 6.5–9.0

Solubility in cold water: Excellent; forms a viscous colloidal solution
Solubility in hot water: Excellent (dissolves in both hot and cold water)
Solubility in organic solvents: Insoluble in methanol, ethanol, acetone, chloroform, benzene
pH stability: 6.5–9.0 (optimal); functional 4–11; limited outside this range
Temperature effect: Viscosity falls as temperature rises; permanent viscosity loss at elevated temperatures
Salt/alkali resistance: High (can replace guar gum in high-electrolyte systems)
Light stability: Resistant to degradation by strong light
GHS Classification: Not classified
JECFA ADI: 0–25 mg/kg body weight/day

Specifications of E466 CMC — Food Grade:
Appearance: White to off-white (cream), odorless, tasteless powder
DS (carboxymethyl groups per anhydroglucose unit): 0.20–1.50
Molecular weight: >17,000 Da (DP ≥100)
Viscosity (1% solution): 25–50,000 mPa·s (depends on grade)
pH (1% solution): 6.5–8.0
Loss on drying: ≤10% (105°C, 3 h)
Sulphated ash: ≤10.0%
Chloride (as NaCl): ≤1.0%
Sodium glycolate: ≤0.4%
Sodium content: 6.5–9.5%
Arsenic: ≤3 mg/kg
Lead: ≤2 mg/kg
Mercury: ≤1 mg/kg
Cadmium: ≤1 mg/kg
Heavy metals (as Pb): ≤10–20 ppm
GHS: Not classified
Storage: Ambient temperature, cool dry place, tightly sealed containers; slightly hygroscopic

Names of E466 CMC:
E466 CMC
E466
Sodium Carboxymethyl Cellulose
Carboxymethyl Cellulose
CMC
NaCMC
SCMC
Sodium CMC
Cellulose Gum
Carmellose
Carboxymethylcellulose Sodium
Carboxy Methyl Cellulose
Sodium Carboxymethylcellulose
Cellulose Carboxymethyl Ether
CMC Gum
Sodium Cellulose Glycolate
Tylose
Celluvisc
Carmellose Sodium
INS 466
E469 (enzymatically hydrolyzed form)
CAS 9004-32-4
HS 39123100