Topic wise notes as per new NCHM-JNU syllabus (for B.Sc HHA & M.Sc HA) are are now available at our new website hospitality.institute
Select Page

Role of Emulsifying agents in food emulsions

by

If you have been through the previous topics of this chapter you must have got enough uses of emulsifying agents in food.

Here are links to previous topics.

A. Theory of emulsification

B. Types of emulsions

C. Emulsifying agents


The use of food emulsifier began with adding monoglyceride and lecithin to margarine. Originally, these substances were only known as emulsifiers. However, as studies progressed, more functions were found and they began to be used in various fields, such as bread, ice cream and cake. Nowadays, emulsifiers are applied to Japanese foods like tofu and minced fish products.

In mayonnaise, the emulsifier is the phospholipids present in egg yolks – they are such successful emulsifiers that as much as 80% oil can be dispersed in the aqueous phase.

Ice cream is another food that would not exist were it not for emulsifiers. It is both a foam and an emulsion, and its texture results from the ice crystals and unfrozen water it contains. But it’s not just creamy products where emulsifiers are crucial – bread and other baked products, where solid particles are dispersed in an airy foam, are enhanced by emulsifiers.


The emulsifiers that are used commercially come from both natural and synthetic sources. They include:

Lecithins (E322) are mixtures of phospholipids such as phosphatidylcholine and phosphatidylethanolamine and are usually extracted from sources such as egg yolk and soybeans. The precise composition of the phospholipids depends on the source. Uses include salad dressings, baked goods and chocolate.

Esters of monoglycerides of fatty acids (E472a-f) are made from natural fatty acids, glycerol and an organic acid such as acetic, citric, lactic or tartaric. The fatty acids are usually from a vegetable source, though animal fats can be used. Products that use them include ice cream, cakes and crisps.

Mono- and diglycerides of fatty acids (E471) are semi-synthetic emulsifiers made from glycerol and natural fatty acids, which can be from either plant or animal sources. They are used in products like bread, cakes and margarine.


 

How useful was this post?

5 star mean very useful & 1 star means not useful at all.

Average rating 5 / 5. Vote count: 4

No votes so far! Be the first to rate this post.

We are sorry that this post was not useful for you! 😔

Let us improve this post!

Tell us how we can improve this post?

Syllabus BHM117

01 Definition and scope of food science

  1. It’s inter-relationship with food chemistry, food microbiology and food processing.

02 Carbohydrates

  1. Introduction
  2. Effect of cooking (gelatinisation and retrogradation)
  3. Factors affecting texture of carbohydrates (Stiffness of CHO gel & dextrinization)
  4. Uses of carbohydrates in food preparations

03 Fat & Oils

  1. Classification (based on the origin and degree of saturation)
  2. Autoxidation (factors and prevention measures)
  3. Flavour reversion
  4. Refining, Hydrogenation & winterisation
  5. Effect of heating on fats & oils with respect to smoke point
  6. Commercial uses of fats (with emphasis on shortening value of different fats)

04 Proteins

  1. Basic structure and properties
  2. Type of proteins based on their origin (plant/animal)
  3. Effect of heat on proteins (Denaturation, coagulation)
  4. Functional properties of proteins (Gelation, Emulsification, Foamability, Viscosity)
  5. Commercial uses of proteins in different food preparations(like Egg gels, Gelatin gels, Cakes, Confectionary items, Meringues, Souffles, Custards, Soups, Curries etc.)

05 Food Processing

  1. Definition
  2. Objectives
  3. Types of treatment
  4. Effect of factors like heat, acid, alkali on food constituents

06 Evaluation of Food

  1. Objectives
  2. Sensory assessment of food quality
  3. Methods
  4. Introduction to proximate analysis of Food constituents
  5. Rheological aspects of food

07 Emulsions

  1. Theory of emulsification
  2. Types of emulsions
  3. Emulsifying agents
  4. Role of emulsifying agents in food emulsions

08 Colloids

  1. Definition
  2. Application of colloid systems in food preparation

09 Flavour

  1. Definition
  2. Description of food flavours (tea, coffee, wine, meat, fish spices)

10 Browning

  1. Types (enzymatic and non-enzymatic)
  2. Role in food preparation
  3. Prevention of undesirable browning