Emulsifier and their use in our food products.

If you take oil and some water and stir the mixture vigorously. Oil droplets will get dispersed in water or water droplets will get dispersed in oil. But this will be temporary. Once you stop the stirring the oil and water may get separated. If you add an emulsifier in the above mixture the formed droplets remain dispersed. A stable emulsion will be formed.


There are two types of emulsions. One is oil in water and the other is water in oil. In the water in oil emulsion water droplets will be in the centre and they will be surrounded by a thin layer of oil. In the other, the centre will be oil and water layer will be around this oil. A good emulsion will last long. If you take a small quantity of emulsion on one of your fingers and rub with another figure the layers should not get separated. Then you can say that the emulsion is good.

An emulsifier consists of a hydrophilic agent and a hydrophobic agent. The emulsifier reduced the surface tension and makes the emulsion stable. When an emulsifier is added to a mixture containing the oil and water, this emulsifier will get coated on each droplet and that will ensure that no two droplets will get attracted to each other.

Emulsifiers used in food production are generally purified natural products. There are some synthetic products also which are similar to natural products. Lecithin which is in egg yolk is a natural emulsifies. It is used in many food products. It will provide a good link between various fats and liquids. Mustard, soy, mono- and diglycerides, guar gum and canola oil are some of the naturally occurring emulsifiers. They will be used in the food industry

Making an emulsifier is a science by itself. If there are natural products which can be used as emulsifiers, they can be extracted from the natural products by using solvent extraction techniques. Synthetic emulsifiers are to be made as per the manufacturing methods developed. The emulsifiers that are to be used in food industry required FDA approval and should be as per the standards prescribed from time to time.

Emulsifiers added to processed foods to get a smooth texture to the item. It will prevent separation of the ingredients. The shelf life of the food items will get enhanced. But too much addition of this item is also not good. We have to optimise the quantity based on the viscosity required for the emulsion. Higher the viscosity of the emulsion higher the shelf life of the emulsion. Generally, a maximum of 2% of the total mass will be used.

You take a little quantity of the emulsifier and add an insoluble substance to that and stir well. You will see a semi-transparent solution. Generally, this phenomenon is called solubilization. Another test you can do is take the mixture of oil and water and then add a little quantity of emulsifier and keep it overnight. There should not be any phase separation in the mixture.

Hi Varghese.

1. A food emulsifier is a surface-active agent. It acts as a border between two immiscible liquids like oil and water and allows them to be blended into stable emulsions. It is also known as an emulgent. Emulsifiers control crystallization, reduce stickiness and also prevent separation.

2. The emulsifiers work by forming physical barriers. These physical barriers keep droplets from coalescing. Emulsifiers contain both hydrophilic (water-loving or polar) head group and hydrophobic (oil-loving, non-polar) tail group. Since it contains both water-loving and oil-loving head and tail group respectively, it is attracted to both polar and non-polar compounds. When emulsifiers are added to an oil-water emulsion, they surround the oil droplet with their non-polar tails extending into the oil and their polar head groups facing the water. The reverse happens in the water-oil emulsion. The non-polar tails extend outward into the oil phase and the polar head groups point to the water droplet. Thus, the emulsifiers lower the interfacial tension between the oil and water phases. It stabilises the droplets and prevents them from coalescing.

Emulsifiers can be positively charged, polar head group, negatively charged head group or uncharged head group i.e. it can be cationic, anionic and non-ionic too. When the charged emulsifiers coat droplets in an oil-water emulsion, the positive or negative charges on the outside of the oil droplets repel each other electrostatically, the helping to keep the droplets separated.

Non-ionic emulsifiers have large, bulky head groups that point away from the oil droplet. These polar head groups clash and even tangle with head groups on other water droplets, thus hindering the droplets from coming together.

According to the application, emulsifiers are used. Cationic emulsifiers are used in low to neutral pH solutions. Anionic emulsifiers are used in alkaline solutions. Non-ionic emulsifiers can be used alone or they can be combined with charged emulsifiers to increase emulsion stability.

3. The common emulsifiers include mustard, soy and egg lecithin, mono and diglycerides, glycerides, monoglyceride derivates, polysorbates, carrageenan, guar gum, canola oil, fatty acid derivates, proteins, sodium stearoyl lactylate, ammonium phosphatide, locust bean gum, xanthan gum etc.

4. Two types of emulsions are created by emulsifiers-
i) droplets of oil dispersed in water
ii) droplets of water dispersed in oil

There is a continuous and dispersed phase within the emulsion. The continuous phase is the water and the dispersed phase is the oil in an oil-in-water-emulsion. In a water-in-oil-emulsion, the oil is the continuous phase.
By applying mechanical force from a blender or a homogenizer, emulsions can be made. This force breaks down the dispersed phase into tiny droplets that become suspended in the continuous phase.

One of the most powerful and oldest forms of an animal-derived emulsifier is Lecithin in egg yolks. It is used to stabilize oil in water emulsions, for example, in mayonnaise and hollandaise sauce.

5. Emulsifiers are used in our food products for a number of reasons.

i) They make the food appealing to us. For example, mayonnaise without the emulsifier would be so unappealing if oil and water separated before it's even used.

ii) Emulsifiers have a huge effect on the structure and texture of many foods. They are used to help in the processing of foods and also to help maintain the quality and freshness of foods.

iii) Emulsifiers help in preventing the growth of moulds in low fat spreads, which would happen if oil and fat are separated.

iv) Some emulsifiers like lecithin are very good for the body. Lecithin can reduce the high level of cholesterol, blood pressure. It also helps in the treatment of Alzheimer's disease.

6. It is important to know about various emulsifiers to recognize them in the ingredients list of the food product. Also, laboratory tests can be done to find out the type of emulsifier used in a food product.

Hope it helps.

Emulsification is a process of dispersing two or more immiscible liquids like oil and water. They make two phases namely organic phase i.e. oil and aqueous phase i.e. water. An emulsifier is used to stabilize by the addition of emulsifier or surfactant.

1. An emulsifier or emulgent is a substance that stabilizes an emulsion or an additive or surfactant used to stabilize processed foods. By the process of emulsification oil is dispersed as small droplets in water and it forms emulsion. But as soon as shaking is stopped, both (oil and water) start to separate. But after addition of emulsifier, oil droplets remain disperser and do not separate, so emulsifier is used to avoid any unwanted change in state of substances.

2. There are two phases in an emulsion one continuous aqueous (water) and other dispersed phase (oil). An emulsifier is a molecule that consists of a water-loving end (hydrophilic head) and an oil-loving end (hydrophobic tail). The hydrophilic head of emulsifier is attached to the aqueous phase and the hydrophobic tail attached to the oil phase. By reduction in surface tension, emulsion remain in has a stabilized form. Addition of emulsifier makes it possible for water and oil to remain in dispersed state and make a stable, homogenous emulsion. In addition emulsifier also interact with proteins or carbohydrates of the food product and can also work like an aerating agent etc.

3. There are many emulsifiers. Some of them are very commonly used in food production. They used to keep products moist or greasy (such as cakes and bread) or to mix fat-soluble substances with water, such as margarine.
Common examples of emulsifiers are as follows:
1. Lecithin : It is found in egg yolk. And used in making sauces and mayonnaise. Lecithin is also used in products like chocolate and baked goods.
2. Mustard: where a variety of chemicals in the mucilage surrounding the seed hull act as emulsifiers.
3. Soy lecithin: Soy lecithin is another emulsifier occurs in soybean and used to bind soy oil and water inside soybean.
4. Mono- and diglycerides
5. Polysorbates,
6. Carrageenan,
7. Guar gum and
8. Canola oil
9. Sodium stearoyl lactylate
10. Ammonium phosphatide,
11. Locust bean gum
12. Xanthan gum
13. Pickering stabilization – uses particles under certain circumstances.

4. The emulsifiers derived from naturally occurring substances and also produced synthetically for commercial use. Actually there are three categories of emulsifiers:
a. Natural: Beeswax is being used in skin care products due to their softening and healing properties. As an emulsifier it also used as a thickener and used in oil-in-water emulsions e.g. creams.
Some other natural emulsifiers are soy lecithin, egg yolk lecithin, candelilla wax, carnauba wax, rice bran wax and organic liquid lecithin.
b. Semi-synthetic: Common example of semi synthetic emulsifier is Mono- and diglycerides of fatty acids which are made from glycerol and natural fatty acids,
c. Synthetic: There are several synthetic emulsifiers e.g. benzethonium chloride, benzalkonium chloride and sodium or potassium oleate etc.

5. Emulsifiers are added in a variety of food products. Some of the common reasons are:
a. Emulsifiers are used in creams and sauces, bakery, and dairy products. They may be derivative of natural products or chemicals. They are used to keep these products fresh and soft like tofu etc.
b. They are also use to increase product shelf life.
c. They increase and maintain smoothness and consistency in product, so that they become more likable.
d. They make products moist or greasy (such as cakes and bread) or to
e. They assist in fat dispersion and use to mix with fat-soluble substances, so that they may remain bind together with water like in margarine.
f. They helps is controlling of fat agglomeration or fat destabilization
g. Emulsifiers promote air incorporation and stabilization of air bubbles in the batter.
h. They also resist shrinkage when they are stored.
i. They also prevent mould growth if the fat and oil separate.

6. We know about naturally occurring emulsifying agents. However, usually they are available in the ingredient list on any product. You can check them on the product ingredient list. Some laboratory tests are also there for confirmation of emulsifying agents in a product.

However, a variety of emulsifiers are used in the packaged products and they have some benefits. But, some care should be taken as they may be harmful if product having emulsifiers are taken regularly. They may harm intestinal functions and may cause inflammation and may increase risk of chronic diseases. They may cause allergic reactions in some people and sometimes may be dangerous. They can also increase risk of heart related problems due to the presence of trans fats.

The point wise details to the query is as under -

1. Emulsifier is a material which when added to two immiscible liquids, mixes them to make an emulsion. It has also got a property of keeping certain items moist and are used in that fashion in items like cake and bread. On the other hand, in many food products like ice creams, low-fat spreads, margarine and salad dressings emulsifier are used to keep these foods in stable emulsion form.

2. Emulsifiers are specific materials which can blend two immiscible liquids with each other and keep them in a stable state. It will also not allow the liquids to separate out from each other. In addition to this they control crystallisation as well as stickiness. They work in two ways. First is by making the droplets of first material into the second liquid and the other one is to make the droplets of second liquid in the first one. Practically it is the making of the emulsion of two liquids. Because of food safety considerations, emulsifiers are to be mentioned along with the other ingredients on the outside of a food packet.

3. There are many substances which can be used as emulsifiers because of their particular property of keeping the things moist or mixing things to make emulsions. In todays food technology, the most commonly used emulsifiers are mustard, soy and egg lecithin, mono- and diglycerides, polysorbates, carrageenan, guar gum and canola oil. By mixing them in appropriate amount we can make emulsions of desired degree.

4. Emulsifiers are readily available as the natural materials as mentioned above or can be prepared from plant, animal or synthetic sources. For different purposes and consistencies of the food products these emulsifiers can be used.

5. The texture of food is also an important part and when we present a food in ice chilled way to the guests then everyone will appreciate the most robust and durable food items in that shape and appearance. Here comes the use of these substances that is Emulsifiers which will keep the different ingredients together in emulsion form and will not allow them to separate out.

6. Emulsifiers are recognised by their proportions of oil water phases or water oil phases or HLB values (Hydrophilic Lipophilic Balance). With this they are easily categorised in oil-water type or water-oil type.

A Food - emulsifier also known as an emulgent is to restore cohesion between two immicible liquids such as oil and water enabling the two to be blended into a stable emulsion. Hence the emulsifier would prevent from any damage from the decomposition.
The function of the emulsifier is to reduce stickiness controlling the crystallisation and prevent the separation of two layers.
They form two types emulsions either droplets of oils appearing in water or droplets of waters dispersed in oil. Within the emulsion, there is a continuity of the dispersed phase. In an oil versus water emulsion, the continious phase is the water and the dispersed phase is the oil.
Emulsion can also be achieved with the application of mechanical - force from a blender or a homogeniser breaking down the dispersed phase into tiny droplets that may appear suspended in the form of continious phase.
Common type of emulsifiers in the modern food production include Mustard, Soy, ,Egg lecithin, Guar- gums, Mono - diglycerides, Polysorbates, Canola - oil etc.
Emulsifiers are used in the varieties of products such as Ice - creams, Marrgarine, Salad - dressing and many more and these are the following reasons-
1) It would increase the self - life of the product.
2) It would retain its homogeneity of the product.
3) There would be more consistency and smoothness of the product and hence it could be a preferred choice among the customers.
4) It helps in controlling fat - agglomeration and fat destabilisation.
5) Emulsifier would resist shrinkage during the process of storage.
However, the manufacturer may use a combination of emulsifiers and such combination may cause some inflammation in the liver and intestines causing the chances of cancer on its consistent consumption.