Emulsifiers and Emulsifier Salts
Emulsifiers are used to help maintain homogenous mixtures of oil and water, much as egg yolk does in mayonnaise. The main active ingredient in egg yolk, lecithin is frequently used as an emulsifier and can be made from other sources such as soya and sunflower. Also commonly used are mono-and- diglycerides of fatty acids derived from fats, both animal and vegetable, and used for fat spreads, in bakery products and a whole range of other foods. Emulsifying salts are specifically used in the production of processed cheese and enable the formation of a cheese spread.
Some additives are used as emulsifiers but are also used in other ways, so some of the additives in this group may also appear as stabilisers, thickeners or gelling agents. In the EU 63 emulsifying agents are permitted compared to 171 in the US and more than 260 in the global Codex Alimentarius food standards.
An emulsifiers name and E number can be used for different materials which can make it difficult to differentiate natural substances from those that are derivatives and may have different properties. For example the term lecithin (E322) includes natural lecithins and their hydrolysed derivatives, which have very different properties, and it is the differing properties of emulsifiers that have led to significant concern over their potential health impacts, particularly in the gut.
Most food emulsifiers work by being active on the surface stabilising emulsions at their interface (e.g. oil and water) and are known as surfactants. Increasing evidence suggests that surfactant emulsifiers may be potentially toxic in the gut and it has been suggested that consumption of these emulsifiers may promote autoimmune diseases by impairing the intestinal barrier function and altering the intestinal microbiota. It has also been suggested that some emulsifiers may increase the absorption of several environmental toxins, including endocrine disruptors and carcinogens. Current toxicity testing of additives do not pick up these potential effects.
All emulsifiers by definition are surfactants, and the potential impact on the microbiome and gut health from the intake of surfactant emulsifiers is discussed following the surfactant emulsifier link below. Gums are also used as emulsifiers and a description of these can be found in the section on thickeners, stabilisers and gums.
Surfactant Emulsifiers
Lecithin E322
Lecithin E322 is a mixture of phospholipids physically extracted from a number of vegetable or animal products. Lecithins are present in eggs, milk, marine sources, rape and cotton seed, but the major commercial lecithins are derived from soya and sunflower. In emulsions phospholipids will dissolve in fat and disperse in water so that they are located at the interface between the two. In addition to acting as an emulsifier lecithin is used to moderate the flow of chocolate during moulding and coating operations, to improve the ‘wettability’ of powders which are designed to be reconstituted and to optimise the gluten network in bakery items. Lecithin can be used in foods in the EU quantum satis and is seen in a very wide range of foods. You cannot discern if lecithin has come from an animal or vegetable source.
Octenyl succinic acid modified gum Arabic (E423)
Octenyl succinic acid modified gum Arabic (E423) is made by esterifying gum Arabic (E414) with a dilute solutionof octenyl succininc acid which introduces lipophilic groups into the molecule so it can act as an emulsifier. It is particularly used flavouring oil emulsions. In the EU it is permitted for use only in icings, sauces, energy drinks and those containing fruit juice and flavouring emulsions.
Polyoxyethlyene sorbitan monolaurate (E432)
Polyoxyethlyene sorbitan monolaurate (E432) is also known as Polysorbate 20 and is a strong hydrophilic surfactant widely used in the food industry for forming oil in water emulsions such as in dressings, sauces and margarines. Its surfactant properties also improves the volume and texture of cakes, modifies fat crystallisation, helps dispersion in coffee whiteners and aeration of whipped cream. It can be used in combination with mono-and diglycerides of fatty acids or other polysorbates to balance emulsion properties and is often found in cakes and cake mixes. In the EU polysorbate 20 is only permitted in a range of products and there are limits in all cases.
Polyethoxyethlene sorbitan polysorbate (E433)
Polyethoxyethlene sorbitan polysorbate (E433) also known as Polysorbate 80 is a water loving surfactant often used with sorbitan esters for forming oil in water emlusions. It is used in margarine, ice cream, frozen desserts, sauces and dressings. In the EU Polysorbate 80 is permitted in specific products with individual maxima in each case.
Polyoxyethlene sorbitan monopalmitate (E434)
Polyoxyethlene sorbitan monopalmitate (E434) also known as Polysorbate 40 is a water attracted surfactant often used in combination with other emulsifiers to stabilise sauces and dressings, in bakery margarines to improve aeration, cake volume and texture. It is also used in coffee whiteners and whipped cream. Polysorbate is permitted in the EU in a range of products with a limit in each case.
Polyoxyethylene sorbitan monostearate (E435)
Polyoxyethylene sorbitan monostearate (E435) also known as Polysorbate 60 is also used for forming oil in water emulsions and is used in bakery margarine, to reduce staling in bread and to improve batter aeration in cakes. It is also used in dressings and sauces and is often blended with sorbitan esters to balance emulsion properties. As with the other polysorbates it is permitted in the EU in specific products with limits in each case.
Polyoxyethlyene sorbitan tristearate (E436)
Polyoxyethlyene sorbitan tristearate (E436) also know as Polysorbate 65 is used to hold the fat in ice cream and to retard the development of fat bloom in chocolate products and retard foam formation during food processing. It is also often used in conjunction with sorbitan esters or other polysorbates and is permitted in specific foodstuffs in the EU with individual limits in each case.
Ammonium phosphatides (E442)
Ammonium phosphatides (E442) also known as Emulsifier YN are obtained by phosphorylation of a mono-and diglyceride produced from an edible fat. Traditionally they are produced from a partially hydrogenated rape seed. This additive is used to modify the viscosity of liquid chocolate making it suitable for moulding or enrobing. It can also be added to couverture, ice cream coatings and various confectionery products where it can substitute for lecithin. Ammonium phosphatides have a neutral flavour profile and do not add to any off-flavours in food even at higher doses. In the EU they are permitted only for use in chocolate and cocoa-based confectionery in levels up to 10g per kg of food.
Sucrose acetate isobutyrate (E444)
Sucrose acetate isobutyrate (E444) also known as SAIB is used to inhibit the separation of oils in soft drinks and is often used in conjunction with gum arabic. In the EU it is only permitted for use in flavoured cloudy drinks containing less than 15% alcohol by volume.
Glycerol ester of wood rosin (E445)
Glycerol ester of wood rosin (E445) also known as ester gum is extracted from pine woodchips and the rosin is reacted with glycerol to give a mixture of di-and triglycerides. It is only permitted for use in the EU in cloudy drinks containing less than 15% alcohol and as a surface treatment for citrus fruit.
Mono- and diglycerides of fatty acids (E471)
Mono- and diglycerides of fatty acids (E471) used widely in many food products and unlike many additives can have a variable composition depending on how it is created. Commercially they are produced by either heating triglyceride fats with and excess of glycerol in the presence of a catalyst or via direct esterification of glycerol with fatty acids. The resulting composition of the mono- and diglyceride mixture is dependent on the amount of glycerol used and the temperature used. To be permitted as an additive the content of mono and diesters must not be less than 70% but this specification permits a wide range of compositional types under one additive name. The fat, fatty acids and glycerol used can be either of animal or vegetable origin and there is no way for consumers to know the source.
Monoglycerides and mixtures of mono-and diglycerides are the most important commercially of all the food surfactants and represent more than 50% of the total food emulsifier market as well as being important intermediates in the manufacture of the E472 series of mono-and diacid esters of mono-and diglycerides, Mono-and diglycerides of fatty acids are used in bread production to enable the gluten to remain plastic and pliable, to improve the uniformity of air bubbles in batter and to stabilise other oil and water emulsions. They are typically found in fat spreads, confectionery, ice cream, bread and cakes, cereals and desserts. In the EU these additives can be used quantum satis.
Acetic acid esters of mono- and diglycerides of fatty acids (E472a)
Acetic acid esters of mono- and diglycerides of fatty acids (E472a) also known as ACETEMS are made by mixing mono-and diglycerides of fatty acids with acetic anhydride from acetic acid or by transesterification. Acetems are insoluble in hot or cold water and are used for aerating and foam stabilising, as lubricants in chewing gum and for moisture resistant coatings. In whipped toppings they act as aerating and emulsifying agents stabilising protein, sugar and fat in foams. Acetems that are solid at room temperature are used to coat and protect foods such as sausages, fruit and cheese which prevents microbiological contamination and moisture migration. Acetems are used in jams and jellies as anti-foaming agents. In the EU acetums are permitted quantum satis.
Lactic acid esters of mono- and diglycerides of fatty acids (E472b)
Lactic acid esters of mono- and diglycerides of fatty acids (E472b) also known as LACTEMS are made by reacting mono-and diglycerides of fatty acids with lactic acid 0r by reacting glycerol with a mix of fatty acids and lactic acid. Lactems are used as emulsifiers frequently in conjunction with more water loving emulsifiers, and are used to improve the incorporation and distribution of air in whipped systems such as cakes, mousses and toppings. In the EU lactems can be used quantum satis.
Citric acid esters of mono- and diglycerides of fatty acids (E472c)
Citric acid esters of mono- and diglycerides of fatty acids (E472c) also known as CITREMS, these are made by reacting mono-and diglyceride of fatty acids with citric acid or by reacting glycerol with a mix of citric acid and fatty acids. Citrems are dispersible in hot water and soluble in oil and are used as emulsifiers to prevent separation of fat during cutting and chopping and to stabilise emulsions in cooked products such as liver sausage. They are also used in cocoa and chocolate products and to stop spattering of margarines during frying. Within the EU they can be used quantum satis.
Tartaric acid esters of mono- and diglycerides of fatty acids (E472d)
Tartaric acid esters of mono- and diglycerides of fatty acids (E472d) also known as TATEMS they are made by mixing mono-and diglycerides of fatty acids with tartaric acid. Tartaric acid is however expensive and as tatems are the most expensive of the E472 series of additives they are rarely produced commercially. They have quantum satis status in the EU.
Mono-and diacetyl tartaric acid esters of mono- and diglycerides of fatty acids (E472e)
Mono-and diacetyl tartaric acid esters of mono- and diglycerides of fatty acids (E472e) also known as DATEMS are made by reacting mono-and diglycerides of fatty acids with diacetyl tartaric acid anhydride in the presence of acetic acid or by esterification with tartaric acid. Datems are used in a wide range of food products, particularly when there is potential for interaction with protein, such as in wheat-based bakery items and egg containing emulsions such as mayonnaise. Datems also stabilise egg proteins and render them less susceptible to coagulation under heat. In yeast raised baked goods datems work as classical emulsifiers ensuring the even distribution of lipids and aids the volume stability of bakery items. Within the EU datems have quantum satis status.
Mixed acetic and tartaric acid esters of mono- and diglycerides of fatty acids (E472f)
Mixed acetic and tartaric acid esters of mono- and diglycerides of fatty acids (E472f) also known as MATEMS are made by reacting mono-and diglycerides of fatty acids with a mixture of tartaric acid and acetic acid. Because matems can exhibit the characteristics of both acetums and datems they can be used as emulsifiers, stabilisers and antifoams. They are typically used in bakery items and have quantum satis status in the EU.
Sucrose esters of fatty acids (E473)
Sucrose esters of fatty acids (E473) are generally used as emulsifiers in oil-in-water emulsions cut can also be used as texturises or to stabilise foam in dairy products or non-dairy equivalents.Sucrise esters also intract with starch, protect proteins from coagulation and promote crystallisation of sugars. They also have some anti-microbial activity. Sucrose esters are permitted in the EU in a range of products such as ice cream, confectionery, sauces, milk alternatives and hot beverage powders with individual maxima.
Sucroglycerides (E474)
Sucroglycerides (E474) are emulsifiers and dispersing aids and help to both improve crystallisation and improve texture in foods such as bakery products, ice cream and non-alcoholic drinks. They are less expensive than sucrose esters, but are not commonly manufactured. They are permitted in the EU in a range of products with individual maxima.
Polyglycerol esters of fatty acids (E475)
Polyglycerol esters of fatty acids (E475) are more polar than mono-and diglycerides of fatty acids so they are used to hold water in water-in-oil emulsions as well as helping with cake aeration and to reduce fat spattering in frying oils. They often work with other emulsifiers to reduce the total amount of emulsifier needed in a product. They are permitted in the EU in a range of products with defined limits.
Polyglycerol polyricinoleate (E476)
Polyglycerol polyricinoleate (E476) also known as PGPR is used to modify the flow characteristics of chocolate and because it is an efficient surfactant to stabilise water-in-oil emulsions in foods such as low fat spreads. PGPR also works with lecithin to increase plastic viscosity and allow lower fat contents in food products. In the EU PGPR is only permitted in low or very low fat spreads and in cocoa and chocolate based confectionery.
Propane -1-2-diol esters of fatty acids (E477)
Propane -1-2-diol esters of fatty acids (E477) are typically produced from palmitic and stearic acid and the esters act as emulsifiers to improve aeration and foam stability in powdered desserts and cakes. They are often used alongside mono-and diglycerides of fatty acids. They are permitted in the EU in a range of products with specific limits in each case.
Sodium stearoyl-2-lactylate (E481) and Calcium stearyl-2-lactylate (E482)
Sodium stearoyl-2-lactylate (E481) and Calcium stearyl-2-lactylate (E482) are used to disperse fat evenly in water and are usually used in emulsifier blends to improve fat suspensions during spray drying, to distribute fat in bread and improve softness during shelf-life. They are permitted in the EU in a range of products with individual limits.
Stearyl tartrate (E483)
Stearyl tartrate (E483) is an emulsifier permitted in bakery foods to a specified level but rarely used.
Sorbitan esters: sorbitan monostearate (E491), sorbitan tristearate (E492), sorbitan monolaurate (E493), sorbitan monooleate (E494) and sorbitan monopalmitate (E495)
Sorbitan esters: sorbitan monostearate (E491), sorbitan tristearate (E492), sorbitan monolaurate (E493), sorbitan monooleate (E494) and sorbitan monopalmitate (E495) are produced by the reaction of the appropriate fatty acid with hexyl anhydride (derived from sorbitol E420). The sorbitan esters are non-ionic emulsifiers and are used to hold aqueous solutions in suspension in fatty materials. They are used to disperse aqueous additives in ice cream, fat spreads and desserts and to provide stable emulsions of fat for spray drying.
Emulsifying salts
Emulsifying salts are used in the production of processed cheeses to disperse proteins and lipids and obtain a homogeneous product.
Sodium lactate (E325) and Potassium lactate (E326)
Sodium lactate (E325) and Potassium lactate (E326) are produced by neutralisation of lactic acid by sodium hydroxide or potassium hydroxide. Their main functions in food are in controlling spoilage and pathogenic bacteria, as a flavouring and in pH regulation where they are used as buffers. Both sodium and potassium lactate can be used in pH-neutral food products such as meat, poultry and fish. Potassium lactate is one of the least bitter potassium salts and can be widely used in the food industry and both lactates are used in confectionery, cooking sauces and other savoury flavours. Lactates control the fermentation of fermented products such as sausages, fermented dairy products and vegetable pickles. Potassium salts are used to reduce sodium contents of finished products. Within the EU they have quantum satis status.
Sodium citrates – monosodium citrate, disodium citrate and trisodium citrate (E331)
Sodium citrates – monosodium citrate, disodium citrate and trisodium citrate (E331) are found widely in nature but produced commercially by neutralising citric acid with sodium hydroxide or carbonate. These are used as acidity regulators, often alongside citric acid. Trisodium citrate is also used as an emulsifier salt in processed cheese. They have quantum satis status in the EU and are typically used in soft drinks, desserts, confectionery and jams.
Potassium citrates (E332)
Potassium citrates (E332) includes monopotassium citrate and tripotassium citrate. These are commercially produced from citric acid and used as acidity regulators, emulsifying salts and a source of potassium in food. Typically used in drinks and confectionery it has quantum satis status in the EU but can have a diuretic effect.
Calcium citrates (E333)
Calcium citrates (E333) includes monocalcium citrate, dicalcium citrate and tricalcium citrate. These are made commercially from citric acid and are used as both acidity regulators, emulsifying salts and sources of calcium. They are often used in dietary supplements and processed vegetables. They have quantum satis status in the EU.
Sodium phosphates (E339) Monosodium phosphate, Disodium phosphate, Trisodium phosphate and Potassium phosphates (E340) Monopotassium phosphate, Dipotassium phosphate, Tripotassium phosphates
Sodium phosphates (E339) Monosodium phosphate, Disodium phosphate, Trisodium phosphate and Potassium phosphates (E340) Monopotassium phosphate, Dipotassium phosphate, Tripotassium phosphates are produced by reacting metal hydroxides with phosphoric acid and the additives in this group are all largely interchangeable. Monometal phosphates are acidic and are used as acidulants in raising agents, but calcium phosphates (E3410 are used more frequently. These sodium and potassium phosphates are more commonly used as chelating agents, buffering agents and occasionally as emulsifying salts in processed cheese. They are also used for protein binding in mixtures of other phosphates. Dimetal phosphates are used as water binders in meat and dairy products preventing water loos and shrinkage during cooking and storage. They are also used to stabilise long life milk products such as evaporated milk, to increase the rate of gelling in instant puddings and cheesecakes and as emulsifying salts in processed cheese products where they provide the required body and melting performance without fat separation. Tripotassium phosphate is used as a buffering agent and texturiser in meat and cheese products and is also used to increase the speed of cooking of pea, beans and cereals. In the EU phosphates are permitted in a range of products with individual maxima in each case.
Di-phosphates (E450)
Di-phosphates (E450) include Disodium diphosphate (SAPP), Trisodium phosphate, Tetrasodium phosphate, Tetrapostassium phosphate, Tetrapotassium diphosphate and calcium dihydrogen diphosphate. Diphosphates are obtained from phosphate rock mined in Morroco, Israel, North America and Russia. These are used widely in the baking industry as raising agents as the acidic diphosphates react with sodium carbonate to release carbon dioxide. The most widely used are disodium diphosphate (SAPP) and the calcium diphosphates. At least five grades of SAPP are available commercially which all differ in their rate of reaction with sodium bicarbonate making them suitable in different conditions. Slower grades are used for large cakes and refrigerated doughs while the faster grades are used in doughnuts and small cakes. The use of SAPP as a raising agent can result in a distinctive aftertaste however, but can be minimised by controlling the acid to bicarbonate ratio. These additives can also be used as emulsifying salts. In the EU the diphosphates are allowed in specific products with individual limits in each case.
