This document discusses emulsifiers. It begins by defining emulsifiers as substances that stabilize emulsions by reducing interfacial tension between oil and water phases. It then covers emulsion formation, classification (O/W, W/O, nanoemulsions, microemulsions), and natural emulsifiers like proteins, phospholipids, saponins, and polysaccharides. Pickering emulsions stabilized by solid particles are also introduced. Applications in food include dairy, bakery and meat products. New trends include double emulsions, delivery of bioactives, and natural alternatives to synthetic emulsifiers. In conclusion, the fields of natural emulsifiers and new emulsion technologies provide opportunities for innovative healthy food products.

1. EMULSIFIERS
VEDANTI S. GHARAT
SEAT NO. :- DBTFAQ-09

2. INDEX
Sr. No. Topics
1. Introduction
2. Emulsion formation
3. Emulsion classification
4. Natural based emulsifiers group
5. Pickering Emulsions
6. Emulsions in food industries
7. New trends in food emulsion system
8. Concluding remarks
9. Reference

3. INTRODUCTION
• They have the ability to act at the interface between two phases, and
so can stabilise the desired mix of oil and water.
• When water and oil are mixed together and vigorously shaken, a
dispersion of oil droplets in water is formed. When shaking stops,
the phases start to separate. However, when an emulsifier is added to
the system, the droplets remain dispersed, and a stable emulsion is
obtained.
• An emulsifier consists of a water-loving hydrophilic head and an oil-
loving hydrophobic tail.
• The food industry depends on using different additives, which
increases the search for effective natural or natural-derived solutions,
to the detriment of the synthetic counterparts.

4. • “An emulsion is a heterogeneous system, consisting of at least one
immiscible liquid intimately dispersed in another in the form of
droplets, whose diameter, in general, exceeds 0.1 μm. Such systems
possess a minimal stability, which may be accentuated by such
additives as surface-active agents, finely divided solids, etc.”
• Emulsifier selection is based upon final product characteristics,
emulsion preparation methodology, the amount of emulsifier added,
the chemical and physical characteristics of each phase, and the
presence of other functional components in the emulsion.
• Pickering emulsions or particle-stabilized emulsions present high
resistance to coalescence and Oswald ripening due to the tight
fixation of the particles to the droplets surface.

6. EMULSION FORMATION
• An emulsifier must have the following characteristics:
(i) adsorb preferably at the interface rather than staying in the bulk of
the fluid and reduce the tension,
(ii) form a condensed layer at the interface that depends on the
partitioning ratio,
(iii) reduce the interfacial tension in the same time scale that the
emulsion is produced.
• The most common method of emulsion formation is the application
of mechanical energy via vigorous agitation.
• The emulsifier is first dissolved in the aqueous or organic phase
depending on the solubility of the emulsifier and on the type of
emulsion desired.
• Next, sufficient agitation to cause surface deformation and large
droplet formation is applied during the addition of one phase to the

7. • The next step is disruption of the droplets. To form a stable emulsion and
prevent coalescence, sufficient emulsifier must be available to adsorb at the
aqueous/organic interphase.
• The emulsifier lowers the Laplace pressure, which facilitates droplet
deformation and disruption.
• After droplet formation, the emulsifier partitions into the interphase of the
aqueous/organic system stabilizing the emulsion.

8. EMULSION CLASSIFICATION
• Emulsions can be classified according to their typology and
structure.
• The first refers to the relative distribution of the immiscible phases
(oil and water), and the latter refers to the arrangement of the
emulsified entities.
• Considering the typology, they can be classified as simple (O/W and
W/O) or double (oil-in-water-in-oil (O/W/O), and water-in-oil-in-
water (W/O/W)) emulsions.

9. • Regarding structure, emulsions can be classified as macroemulsions
(usually called emulsions), nanoemulsions, or microemulsions.
1. Macroemulsions are the most common form of emulsions used in
food industry and are found in a variety of products, including milk,
beverages, mayonnaise’s dips, sauces and desserts.
2. Nanoemulsion are dispersions of nanoscale droplets with a MDD
between 20-100nm.
3. Microemulsion is a thermodynamically stable system and forms
spontaneously with droplet size between 5 to 50nm.

10. System Type Natural emulsifiers Final applications
Emulsions O/W Whey protein Ice-cream
O/W Quillaja saponin and soy lecithin Coffee creamers
W/O/W Whey, rice and pumpkin seed proteins Cheese
O/W Faba bean protein Tofu and yogurts
O/W Pectin Functional foods
O/W Rhamnolipid Beverages
O/W Whey protein, locust bean gum, and iota-
carrageenan
Mayonnaise, salad dressings, and sauces
O/W Modified starch Dairy products
Nanoemulsions O/W Soy lecithin Fruit juices
O/W Quillaja saponin, whey protein, and soy
lecithin
Soft foods, creams, sauces, and salad
dressings
O/W Quillaja saponin and soy lecithin
Functional foods and beverages
O/W Ginseng saponin
O/W Whey protein, gum Arabic, and soy lecithin
O/W Modified starch, whey and casein proteins
Microemulsions W/O Soy lecithin Extraction of edible vegetable oils
W/O Soy lecithin Functional foods and soft drinks
O/W Soy lecithin
O/W Quillaja saponin, Rhamnolipid, and soy
lecithin
Soft drinks and minced meat

11. NATURAL BASED EMULSIFIERS
• Phospholipids- Phospholipids can be obtained from diverse
natural sources, including milk, vegetable oils (soybean, rapeseed
or sunflower), egg yolk, meat and fish.
• Saponins- Saponins are a complex family derived from plants,
constituted by triterpenes or steroid aglycones linked to glycosyl
derived sugar structures.
• Proteins- Diverse proteins (e.g., whey, casein, soy or faba bean
proteins) have been tested in food applications, e.g., emulsions for
the controlled release of lutein, ѡ-3 oil, bioactive hydrophobic
compounds, fish oil or β-carotene.
• Polysaccharides- Only few are authorized as food emulsifiers in
EU, namely alginic acid (E400), gum Arabic (E414), pectin
(E440), cellulose and chemically modified celluloses (E460 to
E469).
• Natural based emulsifiers from microbial sources- They
generate compounds with low Eco toxicity, biodegradability,
stability (pH and salinity) and low critical micellar concentration
(CMC), in addition to biological activity, biocompatibility and
digestibility.

12. PICKERING EMULSIONS
• Pickering emulsion utilizes solid particles alone as stabilizers, which
accumulate at the interface between two immiscible liquids and
stabilize droplets against coalescence.
• They are characterized by a long-term stability and have green
connotations due to the absence of conventional emulsifiers.
• The stability of Pickering emulsions is related with the intrinsic
properties of the oil and water phases and of the particle stabilizers.
• Particles presenting a contact angle (θ) below 90° are generally
suitable for preparing O/W emulsions, whereas θ values greater than
90° indicate good stabilizers for W/O emulsions.
• At 90°, the particle is immersed equally in both phases.

13. EMULSIONS IN FOOD INDUSTRIES
• Several different types of bakery
products.
• Cake volume can be increased upon
addition of several different emulsifiers.
• Cookie characteristics (volume, top
grain, and, particularly, spread ratio) can
be improved with the addition of the
appropriate emulsifier.
• Emulsifiers in ice cream improve fat
dispersion, facilitate fat–protein
interactions.
• Emulsifiers can be used as crystal
structure modifiers in mixtures of
triglycerides. Certain emulsifiers can also
be used to control product viscosity in
cream fillings and in chocolates.
• Emulsifiers have been utilized in the
production of meat analog products.

14. NEWTRENDS IN FOOD EMULSION SYSTEMS
Emulsion type Oil phase Emulsifier Highlights
O/W Vegetable oil Orange pulp and peel powders Base emulsions for food applications
O/W Orange essential oil Pea protein concentrate and soy protein
isolate
Encapsulation of flavors for the food
industry (powder form)
O/W Sunflower, soybean,
MCT, and orange oils
Crude saponins isolated from onion skin
wastes
Food nanoemulsions (stable
emulsions, except at acidic pH and
high ionic strength)
O/W Paprika oleoresin Whey protein and gum Arabic, and soy
lecithin
Food and beverage systems for the
delivery of carotenoids
O/W Hemp seed oil Aesculus hippocastanum L. extract Food nanoemulsions with enhanced
nutritional properties
O/W Almond, mustard,
olive, and soyabean
oils
Biosurfactants isolated from Candida
albicans SC5314 and Candida
glabrata CBS138 yeast strains
Food emulsions with improved
antibacterial capacity
O/W Corn and sunflower
oils) /
Biosurfactant isolated from Candida utilis Food emulsions with promising
properties for salad dressings
O1/W/O2 O1 – Sunflower; O2 -
palm oil
Primary emulsion - gelatin, xanthan gum;
Secondary emulsion - solid fat crystals
Oil encapsulation systems
for texturizing reduced-fat agents

15. CONCLUSION
• A clear driving force towards using natural emulsifiers and the re-
emerging importance of the Pickering emulsions.
• The six main identified families of natural emulsifiers were
phospholipids, saponins, proteins, polysaccharides, emulsifiers from
microbial sources and Pickering stabilizers.
• An analysis of current trends in food emulsion-based products was
discussed, putting in evidence the emulsions increasing role as
delivery systems of bioactives to support innovative fortified foods
advances and the increasing interest in systems based on double
emulsions, which provide the opportunity to combine bioactives of
different nature.
• Overall, the field of natural-based emulsifiers combined with the new
trends in emulsion technology can, hopefully, be the basis of a new
generation of healthy and nutritious food products.

16. REFERENCES
• 1. Emulsion and it’s Applications in Food Processing – A Review Adheeb Usaid
A.S1 , Premkumar.J2 and T.V.Ranganathan3 1.Bachelor of Engineering,
2.Research Scholar, 3. Professor Department of Food Processing and Engineering
School of Biotechnology and Health Sciences, Karunya University, Coimbatore-
641114, Tamilnadu, India.
• 2. New Trends in Natural Emulsifiers and Emulsion Technology for the Food
Industry Written byArantzazu Santamaria-Echart, Isabel P. Fernandes, Samara C.
Silva, Stephany C. Rezende, Giovana Colucci, Madalena M. Dias and Maria
Filomena Barreiro. Submitted: February 12th, 2021 Reviewed: August 11th,
2021 Published: September 1st, 2021.
• 3. Functions of emulsifiers in food systems- N. Krog -Journal of the American
Oil Chemists’ Society volume 54, pages124–131 (1977).
• 4. Emulsifiers in Food Technology: Second Edition January 2015
• DOI:10.1002/9781118921265 Authors: V. Norn.
• 5. Emerging Emulsifiers: Conceptual Basis for the Identification and Rational
Design of Peptides with Surface Activity-Fabian Ricardo, Diego Pradilla, Juan
C. Cruz, and Oscar Alvarez.

17. THANKYOU!