Emulsifiers and texture modifiers are important ingredients used in ice cream production. Emulsifiers help improve texture by facilitating fat globule agglomeration and stabilizing air cells. They are classified based on chemical structure (natural, synthetic, auxiliary) and mechanism of action (mono/multilayer films). Common emulsifiers include mono/diglycerides, polysorbate 80, and egg yolk. Texture modifiers like gelatin, starches, gums, and lecithin help control texture attributes like hardness and mouthfeel. Regulations specify permitted emulsifiers for different food products.
1. Emulsifier & Texture Modifier
Submitted To Submitted By
Dr. Rajan Sharma Shubham Kalbande (22-M-DT-12)
DC Division, NDRI Jitendra Sharma (22-M-DT-13)
Manoj Goriya (22-M-DT-14)
2. Outlines
Introduction.
Mechanism of Action in Ice-Cream.
Classification based on chemical structure.
Classification based on Mechanism of Action.
HLB Concept.
Permitted Emulsifier by FSSAI
Texture Modifier
3. Introduction
Emulsifiers
“Emulsifiers” are the
“substances which when
added to food, are capable
of facilitating a uniform
dispersion of oils and fats
in aqueous media or vice
versa.”
Emulsifiers are substances
that are soluble both in
water as well as in fat.
4. Mechanism of Action in Ice-Cream.
Emulsifiers de-emulsify the fat globule
membrane formed during homogenization.
This de-emulsification facilitates the
agglomeration and coalescence of fat globules.
Then this agglomerated fat globules stabilize the air
cells.
Thus emulsifiers are used to improve whipping
qualities of ice-cream by producing small ice
crystals and smaller air cells, resulting into smoother
ice-cream texture and drier, stiffer ice-cream.
5. Classification based on chemical structure
Natural Emulsifier
Synthetic Emulsifier
Auxiliary Emulsifier
Finely Dispersed Solids Emulsifier
6. Natural Emulsifying Agents
Natural Emulsifying Agents are substances derived from either
vegetable sources such as acacia, tragacanth, alginates, xanthan,
and pectin or animal sources such as gelatin, egg yolk, casein,
cholesterol, wax, and lecithin.
These materials form hydrophilic colloids when added to water
and generally produce o/w emulsions.
Synthetic Emulsifying Agents
Synthetic Emulsifying Agents are very effective at lowering the
interfacial tension between the oil and water phases because the
molecules possess both hydrophilic and hydrophobic properties.
Ex. Polysorbate 20, Polysorbate 80, Sodium lauryl sulphate etc.
7. Auxiliary Emulsifying Agents
Auxiliary emulsifying agents are compounds that are generally incapable
of forming stable emulsions.
They act as thickening agents and thus help to stabilize an emulsion.
Ex. Glyceryl monostearate, Methylcellulose, Sodium
carboxymethylcellulose, and Stearic acid etc.
Finely Dispersed Solids Emulsifying Agents
Finely dispersed solids are emulsifiers that form particulate films around
the dispersed droplets, producing emulsions that are coarse-grained but
have considerable physical stability.
Ex. Bentonite, and Magnesium Aluminum Silicate.
8. Classification based on Mechanism of Action
Monomolecular Films forming
Emulsifiers
Multimolecular Films forming
Emulsifiers
Solid Particle Films forming
Emulsifiers
9. Monomolecular Films forming Emulsifiers
Those emulsifiers are capable of stabilizing an emulsion by forming a
monolayer of adsorbed ions at the oil-water interface.
If the emulsifier forming the monolayer is ionized, the presence of
strongly charged and mutually repelling droplets increases the
stability of the system.
For example, Potassium laurate and Sodium dodecyl sulfate etc.
Multimolecular Films forming Emulsifiers
They form multimolecular films around droplets of dispersed oil.
They act as a coating around the droplets and render them highly
resistant to coalescence, even in the absence of well-developed
surface potential.
For example, hydrated lyophilic colloids.
10. Solid Particle Films forming Emulsifiers
Small solid particles that are wetted to some degree by both
aqueous and non-aqueous liquid phases act as emulsifying agents.
If the particles are too hydrophilic, they remain in the aqueous
phase; if too hydrophobic they are dispersed completely in the oil
phase.
For example, Hydrophilic colloids, Acacia, and Gelatin etc.
11. Properties of Individual Emulsifier
1. Mono/Di glycerides
Mono- /diglycerides are mixtures of monoglycerides and
diglycerides.
They normally contain 40-60% monoglyceride, together with
diglyceride.
Mono- and diglycerides are surface active because the glycerol
end of the molecule is hydrophilic and the fatty acid end is
hydrophobic.
Fully saturated mono-/diglycerides that contain predominantly
stearic and palmitic acids, such as glycerol monostearate, are often
used for ice cream production @ 0.3%.
12. 2. Sorbitanesters
The sorbitan esters are similar to monoglycerides in that the sorbitanesers
have a fatty acid molecule such as stearate or oleate attached to a sorbitol
molecule, whereas the mono glycerides have a fatty acid molecule attached
to a glycerol molecule.
To make the sorbitan esters water soluble polyoxyethylene groups are
attached to the sorbitol molecule.
Polysorbate 80, polyoxyethylene sorbitan monooleate is the most common
of these sorbitan esters.
Polysorbate 80 is a very active drying agent in the ice cream and is used in
many commercial stabilizer/emulsifier blends.
Added @ 0.1-0.2 %
13. 3. Egg Yolk
Egg yolk, which contains several components with emulsifying
properties, notably lecithin, is often used in all-natural premium or
homemade ice creams.
Egg yolk has the approximate composition (by weight) of 50% water,
16% protein, 9% lecithin, 23% other fat, 0.3% carbohydrate and 1.7%
minerals.
Lecithin consists of phosphatides and phospholipids.
Egg yolk solids are normally used at about 0.5-3%.
High concentrations are only used for super- premium products, and can
give the ice cream an eggy flavour.
14. How to choose an Emulsifier ?
Hydrophilic-Lipophilic Balance
HLB is an index of the solubilizing properties of emulsifiers and indicates
the type of emulsion (o/w or w/o).
HLB values can be calculated based on the molecular structure of
the emulsifier
The values range from 0 to 20
Emulsifiers with low HLB values are more oil-soluble (lipophilic),
while those with higher values are more water-soluble (hydrophilic.
In general, emulsifiers with HLB values of 3–6 are lipophilic and
best suited for w/o emulsions.
15.
16. Emulsifiers permitted for use in various foods by
FSSAI
Polyglycerol esters of fatty acids and Polyglycerol ester of interesterified
Ricinoleic acid are permitted for use in bakery and chocolate products
but only at 0.2 per cent by weight.
Diacetyl Tartaric acid esters of Mono and Diglycerides may be used in
bread and cakes
Starch phosphate, a gum arabic substitute, may be used in syrup, ice-
cream powder, salad dressing and pudding to a maximum extent of 0.5
per cent.
17. Conti…..
Modified food starches (derivative starches) may be used in
confectionery, flavours, dairy products (where use of emulsifier/stabiliser
is allowed per regulations) glazes, icings, gravies, sauces, soups,
coatings up to a maximum concentration of 0.5 per cent by weight.
Modified food starches (derivative starches) may be used in snacks,
frozen potato products, baked foods, and salad dressing/mayonnaise, up
to a maximum concentration of 5 per cent by weight.
18. Conti…
The emulsifying and stabilising agents may be added to flavouring
agents.
Emulsifying and stabilising agents that are permitted to be added to
Fruit products are
a) Pectin
b) Sodium alginate
c) Calcium alginate
d) Alginic acid
e) Propylene glycol alginate
Emulsifying and stabilizing agents as defined under “the names of the
emulsifying and stabilising agents” may be added to frozen desserts
20. What is Food Texture ?
Food texture is a term that describes the sensory experiences
of a food product that can be perceived by visual, audio,
tactile, and mechanical receptors.
Food texture which can indicate the hardness, crispiness,
crunchiness, softness, springiness, tackiness, and other
attributes of food.
Food texture is also an important factor for consumers liking,
preference, and quality perception of food
21. Texture Modifier Agents :
1. Gelatin
2. Agents from Plant Materials
3. Agents from algae and sea weeds
4. Agents from fermentation processes
5. Lecithin
22. 1. Gelatin
Gelatin is made from animal collagen. Collagen consists of well-ordered
polymeric chains of proteins
collagen
Heat Treatment Gelatin
The two main building blocks of
gelatin are aspartic acid and
lysine, these molecules have
several polar groups that can
interact with water molecules.
23. 2. Agents from Plant Materials :
Agents is obtained from a wide range of plant materials, generally are
polysaccharides.
Corn (or potato) starch
Attract and accommodate large quantities of water molecules in between the
polymer chains.
Pectin
It is a well-known household gelling agent (E440) widely used in jam making.
Its gelling effect requires high sugar content in a slightly acidic environment.
Guar gum (E412)
It is a stabilizer and thickener.
gelling agent but only in the presence of calcium ions
Methylcellulose (E461)
Methylcellulose is a gelling agent and potent foam stabilizer.
24. 3. Agents from algae and sea weeds
A range of algae and sea weeds are a rich resource for the isolation of
different gelling agents.
Agar
Agar is obtained from seaweed, a gelling agent (E406).
Carrageenan
Carrageenan is obtained from red algae (Irish moss), a gelling agent (E407,
E407a). It is the usual vegetarian alternative to gelatin.
Alginates
Alginates are obtained from brown algae, they are a range of gelling and gum-
forming agents (E400-E404)
Alginates are commonly used as food thickeners in the food industry.
25. 4. Agents from fermentation processes
Agents are obtained as a by-product of bacterial sugar fermentation.
Gellan gum
Gellan gum is a by-product of sugar fermentation (E418), a powerful gelling
agent that is widely used in the food industry.
Xanthan gum
Xanthan gum is another by-product of fermentation (E415), a powerful
thickener and stabilizer.
Give a pleasant mouth feel because xanthan gum can also act as an emulsifier
( i.e. Ice-cream)
26. 5. Lecithin
Lecithin usually extracted from egg yolks or soy beans (E322).
Lecithin is a highly effective emulsifier.
It belongs to a class of compounds with so called amphiphilic properties,
that is these compounds are attracted both by water and by fatty
compounds.
These are all phospholipids