Carboxymethyl Cellulose
Synonyms: sodium carboxymethylcellulose, sodium carboxymethyl cellulose, carboxymethylcellulose, carboxymethyl cellulose, CMC, sodium CMC, or cellulose gum, Carboxymethylcellulose, carmellose, E466.
Carboxymethyl cellulose can control ice crystal growth in ice cream or as a rheology modifier in yogurt formulations. Carboxymethyl cellulose can stabilize milk products against casein precipitation when acidifying milk. CMC forms stable soluble complexes with casein at pH values of 3–6, where casein is insoluble.
Carboxymethyl cellulose (CMC) or cellulose gum is a cellulose derivative with carboxymethyl groups (-CH2-COOH) bound to some of the hydroxyl groups of the glucopyranose monomers that make up the cellulose backbone.
It is often used as its sodium salt, sodium carboxymethyl cellulose.
Carboxymethylcellulose
Sodium Carboxymethyl cellulose is an anionic polyelectrolyte, soluble in water, whose properties allow applications such as thickening agent, emulsifier, adhesive binder, wetting, dispersant, etc
Other names
Synonyms: sodium carboxymethylcellulose, sodium carboxymethyl cellulose, carboxymethylcellulose, carboxymethyl cellulose, CMC, sodium CMC, or cellulose gum, Carboxymethylcellulose, carmellose, E466
Identifiers
CAS Number
9004-32-4
EC / List no.: 618-378-6
CAS no.: 9004-32-4
Carboxymethyl cellulose is widely used in food products to absorb and hold water, to control crystal growth, to thicken, as a binder, to increase shelf life, and to provide desired texture or body.
As Carboxymethyl cellulose is anionic it can form complexes with milk proteins depending on the formulation.
In addition, high salt concentration has negative influence on viscosity due to masking of electrostatic interactions between CMC chains.
Carboxymethyl cellulose can be used to control ice crystal growth in ice cream or as a rheology modifier in yoghurt formulations
Carboxymethyl cellulose’s largest volume use is in the preparation of dry pet foods that form their own gravy when warm water is added.
Its second largest use is in the preparation of ice cream, sherbets, and other frozen desserts.
Carboxymethyl cellulose is the primary stabilizer in most ice cream products, where it is used to prevent growth of ice crystals.
Keeping ice crystals small maintains the smooth, creamy consistency of the product.
Carboxymethyl cellulose also controls sugar crystal size in fondants.
Carboxymethyl cellulose is used when proteins must be stabilized, such as in yogurt, fruit, soy, and other acidic drinks containing protein.
Carboxymethyl cellulose, a polyvalent anion, can stabilize protein dispersions, especially near their isoelectric pH value where they are least soluble, because the protein molecules will have multiple positive charges and can bind to CMC molecules.
Using Carboxymethyl cellulose, milk products can be stabilized against casein precipitation when milk is acidified because CMC forms stable soluble complexes with casein at pH values in the range 3–6 where casein is insoluble.
Because of its rapid hydration, it affects hydration of other dry mix components.
Carboxymethyl cellulose is both a binder and an extrusion aid in the preparation of pet foods and other extruded products.
In baked goods, like cakes, Carboxymethyl cellulose is added to adjust the consistency of the batter, to increase product volume, to improve the quality of the finished product, to provide moisture retention, and to prolong freshness
Carboxymethylcellulose (CMC) is an anionic, water-soluble cellulose derivative.
Solubility of CMC depends on the DP as well as the degree of substitution and the uniformity of the substitution distribution.
Water solubility of Carboxymethyl cellulose would increase with decreased DP and increased carboxymethyl substitution and substitution uniformity.
The viscosity of the solution increases with increasing DP and increasing concentration.
Carboxymethyl cellulose is soluble in water at any temperature.
Because of its highly hygroscopic nature, CMC hydrates rapidly.
Rapid hydration may cause agglomeration and lump formation when the CMC powder is introduced into water.
Lump creation can be eliminated by applying high agitation while the powder is added into the water or preblending the CMC powder with other dry ingredients such as sugar before adding into water.
Due to its high solubility and clarity of its solutions, CMC is commonly used in beverages and beverage dry mixes to provide rich mouthfeel.
Carboxymethyl cellulose is also used in acidified protein drinks to stabilize protein and prevent it from precipitating.
Carboxymethyl cellulose is also added to syrup and sauce formulations to increase viscosity.
Bakery is another application where Carboxymethyl cellulose is commonly used to improve the quality and the consistency of the end product.
In tortilla breads, for example, Carboxymethyl cellulose is used to improve the process ability of the dough and the textural properties of the end product, including foldability and rollability.
CMC – usually forms a clear, colourless and tasteless solution. It is cold water soluble and some grades have a tolerance to high concentrations of sugar. It is available in a wide range of viscosities and has good heat stability. CMC is a good film former.
Ice cream: CMC is a common stabilizer in ice cream. It is cold water soluble and this gives it an advantage in ice cream mixes that are not subject to high temperatures. Unlike locust bean gum CMC does not give the ice cream any added melt-down resistance. CMC is more commonly used in the USA than in Europe and this may be related to a higher proportion of the European market being novelty items that benefit from improved melt-down resistance.
Bakery: CMC is commonly used in cakes, muffins and tortillas to improve the texture of the product by increasing moisture retention.
Beverages: CMC is used as a stabilizer in fruit drinks and in drink concentrates. Fruit drinks typically consist of fruit juice that is diluted with water. To improve the taste and texture of the drink a citric acid/citrate buffer is usually added, some extra sugar and CMC can be added to improve the mouthfeel of the drink. Low calorie drinks that do not have the viscosity contribution from the added sugar will have a very thin and watery mouthfeel without the addition of a viscosity modifier.
Product types
Functions
Beverage mixes
Alcohol tolerance
Cake, doughnut, and related mixes:
Batter thickener
Humectant (improves texture and extends shelf life)
Increases volume (film former)
Cheese spreads
Protective colloid
Dietetic foods
Thickener
Bodying agent
Dressings
Thickener
Dry pet food
Makes gravy when water is added
Dry-powder fruit drink mixes and salad dressings:
Suspending aid
Rapid hydration:
Extruded products
Lubricant
Binder
Film former
Processing aid
Fondants
Inhibits sugar crystal growth
Frozen and dried egg white
Protein stabilizer
Hot cocoa mixes
Thickener
Ice cream and other frozen dessert products
Inhibits ice crystal growth
Improves mouthfeel, body and texture
Stabilizes casein
Icings and frostings
Inhibits sugar crystal growth
Prevents moisture loss.
Meat emulsions
Texturizer
Binder
Milk products
Protein stabilizer
Pie fillings
Improves texture
Prevents syneresis
Puddings
Inhibits sugar crystal growth
Sauces
Suspending aid
Syrups
Transparent thickener for low-calorie pancake syrup
Toppings
Holds moisture
Prevents syneresis
There is no limit to the concentration of Carboxymethyl cellulose that may be used in food products, but it should be used with good manufacturing practices in mind.
Ingredient labels on products containing CMC may read sodium carboxymethylcellulose, sodium carboxymethyl cellulose, carboxymethylcellulose, carboxymethyl cellulose, CMC, sodium CMC, or cellulose gum.
Preparation
Carboxymethyl cellulose is synthesized by the alkali-catalyzed reaction of cellulose with chloroacetic acid.
The polar (organic acid) carboxyl groups render the cellulose soluble and chemically reactive.
Following the initial reaction, the resultant mixture produces approximately 60% CMC and 40% salts (sodium chloride and sodium glycolate); this product is the so-called technical CMC, which is used in detergents.
An additional purification process is used to remove salts to produce pure CMC, which is used for alimentary and pharmaceutical applications.
An intermediate “semi-purified” grade is also produced, typically used in paper applications such as the restoration of archival documents.
The functional properties of CMC depend on the degree of substitution of the cellulose structure, as well as the chain length of the cellulose backbone structure and the degree of clustering of the carboxymethyl substituents.
Uses
Introduction
CMC is used as a viscosity modifier or thickener, and to stabilize emulsions in various products, both food and non-food.
Carboxymethyl cellulose is used primarily because it has high viscosity, is nontoxic, and is generally considered to be hypoallergenic, as the major source fiber is either softwood pulp or cotton linter.
Non-food products include products such as toothpaste, laxatives, diet pills, water-based paints, detergents, textile sizing, reusable heat packs, various paper products, and also in leather crafting to help burnish edges.
Substance names and other identifiers
Cellulose, carboxymethyl ether, sodium salt
IUPAC names
2,3,4,5,6-pentahydroxyhexanal acetic acid sodium hydride
acetic acid; 2,3,4,5,6-pentahydroxyhexanal; sodium
Carboximethilcelullose
Carboxymethyl cellulose
Carboxymethyl Cellulose Sodium
Carboxymethyl cellulose sodium salt
Carboxymethyl cellulose, sodium salt
Carboxymethylcellulose
carboxymethylcellulose
Carboxymethylcellulose sodium salt
Cellulose carboxymethyl ether sodium salt
Cellulose Gum
Cellulose, carboxymethyl ether, sodium salt
Na carboxymethyl cellulose
sodium carboxy methyl cellulose
sodium carboxyl methyl cellulose
SODIUM CARBOXYMETHYL CELLULOSE
Sodium Carboxymethylcellulose
Sodium carboxymethylcellulose
sodium cellulose carboxymethyl ether
Trade names
Carboximetilcelulosa
Other names
Carboxy methyl cellulose sodium
Carboxymethyl cellulose
carboxymethyl cellulose sodium salt
carboxymethyl cellulose sodium salts
Carboxymethyl ether cellulose sodium salt
Carboxymethylcellulose Sodium Salt
Carboxymethylcellulose, sodium salt
cellulose carboxymethyl ether sodium salt
Cellulose, Carboxymethyl ether, Sodiu
SODIUM CARBOXYMETHYL CELLULOSE
Sodium carboxymethyl cellulose
Sodium Carboxymethylcellulose