Emulsifiers

Two types of simple emulsion

water
in oil (w/o)

oil in water (o/w)

degree of division of the inner phase

quality/stability of the interfacial film

viscosity of the outer phase

ratio & the specific weight of the
volumes of the two phases

Nonionic

uncharged molecules relatively insensitive to effects of pH and salt content. Most commonly used food emulsifier type.

Example: mono- and diglycerides, sorbitan
esters, sucrose esters, polysorbates,
polyoxyethylene glycol oleates (all contain an – OH functional group)

Anionic

posess a negative electrical charge

e.g., Stearoyl lactylates, diacetyl tartaric esters of monoglycerides (DATEM), succinylated monoglycerides; functionality may be markedly influenced by pH and ionic strength.

Cationic

Possess a positive electrical
charge topic

e.g., amine compounds. Not used as food additive (toxic)

Amphoteric

Possess both positive and
negative charges

e.g., various lecithins; may
act as anionic or cationic emulsifier,
depending on pH of the system.

Mono- & Di-glycerides

Most commonly used emulsifiers

Highly lipophilic with HLB values
range from 1 to 10

Used in bakery products, frozen
desserts, icings, toppings, and
peanut butter

Sucrose Esters

Are the mono-, di-, and triesters
of sucrose with fatty acids

Usually with HLB values from 7
to 13

Sorbitan Esters

Produced by the reaction of
sorbitol and stearic acid

HLB = 4.7

Used in conjunction with
polysorbates in oil toppings,
cake mixes, etc.

Stearoyl Lactylates

example of ionic emulsifier

Form strong complex with
gluten in starch

Especially valuable in baked
products

Lecithin and Derivatives

example of amphipilic emulsifiers

Rich in egg yolk

Widely used in baked goods, low-fat baked
goods, chocolate, instant foods, confectionery
products, and cooking spray

emulsion stability, stabilize
aerated systems, and control
agglomeration of fat globules

modify texture, shelf life, and
rheological properties by complexing
with starch and protein components

improve the texture of fat-based foods by controlling the polymorphism
of fats

reduce surface tension between
the two immiscible phases due to their molecular structure.

have both a polar group with an affinity for water (hydrophilic), and a nonpolar group with an affinity for oil (lipohilic).

presence of both regions on the
emulsifier molecule allows them to
orient themselves at the phase
interface & lower the interfacial energy that leads to instability

stabilise emulsions by means of monomolecular interfacial
films & also by formation of steric and/ or electrical barriers that prevent
coalescence of the dispersed droplets

expresses the balance of size and
strength of the hydrophilic (water loving or polar) and the lipophilic (oil loving or nonpolar) groups on the emulsifierSubtopic

High HLB values (HLB > 10) indicate
relatively more polar (hydrophilic)
molecules; More lipophilic emulsifiers have HLB values from 1 – 10

used to describe the emulsifying properties of nonionic emulsifiers

" HLB of 3 – 6 : a good w/o emulsifier
" HLB of 7 – 9 : a good wetting agent; can be used for w/o or o/w emulsifier
" HLB of 10 – 18 : a good o/w emulsifier

Bread, Rolls, Buns

Dough conditioning/strengthening – emulsifiers that aid in development of less tacky, more extensible dough that are processed through machinery
without tearing or sticking – exert their effect during fermentation, mechanical handling, shaping and transport, as well as during proofing and the first part the baking time

Examples of dough conditioners: calcium
stearoyl lactylate, sodium stearoyl lactylate (SSL), ethoxylated onoglycerides (EOM), succinylated monoglycerides (SMG), and polyoxyethylene sorbitan monostearate (PS60)

Cakes

Cake batters have been described as complex w/o emulsions or air-in-fat foams, consisting of suspended flour particles, dissolved sugar, and proteins.

Emulsifiers added to fat-containing batters function to (1) stabilize the aerated structure and (2) promote a finer distribution of the fat droplets.

Confectionery Products & Coatings

Emulsifiers are used primarily to
inhibit bloom, stabilize gloss, &
improve palatability

The bloom defect can be retarded with
the use of emulsifiers functioning as
crystal modifiers

Frozen dairy products – Ice Cream

function as aerating
agent and foam
stabiliser

emulsifiers
stabilize the foam by
actually de-stabilizing
the product's emulsion.

displace the protein from the fat globule surface to the aqueous phase

Noodle & Pasta

make a rigid complex with
starch to protect starch granules and
improve the quality of starchy foods

fresh noodles, an emulsifier makes easy
to handle dough and increases the water
absorption rate by 1 to 2%.

macaroni and spaghetti, emulsifiers
provide a feeling of elasticity, and a
smooth uniform surface which inhibits
sticking after boiling.

Select an emulsifier after considering the functional requirements of the food system, the method of processing, and the form of the finished product

Determine the HLB requirements for the food system – involves screening emulsifiers over a range of HLB
values & several concentrations