Microencapsulation for Development of Functional Dairy Food

1. Microencapsulation for Development
of Functional Dairy Food
By:
Solanki Manoj
Department of Dairy Chemistry, N.D.R.I.,Karnal

2. MICROENCAPSULATION
• It is defined as a technology of packaging solids,
liquids or gaseous materials in miniature, sealed
capsules that can release their contents at
controlled rates under the influences of specific
conditions.
Active ingredient > Process > coated particle

3. Terms Related To Encapsulation
Wall/
capsule
Suspending Dehydration
liquid TERMS media
Core
material

4. WHY ENCAPSULATE???????
PROTECTION
CREATE NEW
FUNTIONAL IMMOBILIZE
FOOD
WHY
ENCAPSULATE
ENHANCED CONTROLLED
ACCEPTABILITY RELEASE

5. Properties of Ideal Coating Material
Good rheological properties at high concentration and easy for manipulation
during the process of encapsulation.
Ability to disperse or emulsify the active material and stabilize the emulsion
produced.
Non-reactivity with the material to be encapsulated both during processing
and on prolonged storage.
Ability to seal and hold the active material within its structure during
processing or in storage.
Complete release of the solvent or other materials that are used during the
process of encapsulation, under desolvenization conditions.

6. Ability to provide maximum protection to the active material
against environmental conditions (e.g., heat, light, humidity).
Solubility in solvents acceptable in the food industry, e.g., water,
ethanol, etc.
Ability to meet specified or desired capsule solubility properties
and active material release properties.
Economy of food-grade substance.
Approved by controlling authority.

7. Methods of Encapsulation
• Coacervation
• Co-crystalization
• Molecular inclusion
• Spray drying
• Spray cooling/chilling
• Extrusion
• Fluidized Bed
• Melt injection
• Liposome

8. Coacervation
• Coacervation microencapsulation is the phase
separation of one or many hydrocolloids from the initial
solution and the subsequent deposition of the newly
formed coacervate phase around the active ingredient
suspended or emulsified in the same reaction media.
• Coacervation is a unique microencapsulation technology
because of the very high payloads achievable up to 99%
and the controlled release possibilities based on
mechanical stress, temperature or sustained release.
• Coacervation is typically used to encapsulate flavour oil
and can also be adapted for the encapsulation of fish
oils, nutrients, vitamins, preservatives and enzymes.

9. Coacervation Formation

10. Co-Crystallization
Syrup blend Flavour
material
Concentration
Supersaturated solution
Transformation or
crystallization
Microsized crystallization
(incorporated product)
Agglomeration
Drying milling and screening
Functionally crystallized product

11. Molecular Inclusion
• β Cyclodextrins are enzymatically
modified starch molecules, which
can be made by the action of
cyclodextrin glucosyltransferase
upon starch. After cleavage of
starch by the enzyme, the ends
are joined to form a circular
molecule.
• The inner hydrophobic cavity of β
cylclodextrin is torus shaped,
where core material can fit and
released after heat treatment
β cylclodextrin

12. Spray Drying
Spray Drying is the most commonly used
encapsulation method in the food industry.
The process is economical and flexible uses
equipment that is readily available, and produces
particles of good quality.
The process involves three basic steps:
Preparation of a dispersion or emulsion to be processed
Homogenization of the dispersion and
Atomization of the mass into the drying chamber.
Spray dried ingredients typically have a very small
particle size (generally less than 100µm) which makes
them highly soluble.

13. Spray drying contd….
Typical shell materials include gum acacia,
maltodextrins, hydrophobically modified starch
and mixtures. Other polysaccharides like
alginate, carboxymethylcellulose and guar gum.
Proteins like whey proteins, soy proteins, sodium
caseinate can be used as the wall material in
spray drying.

14. Multistage Spray Dryer

15. Spray Cooling/ Chilling
Spray cooling/chilling is the least expensive encapsulation
technology.
It is used for the encapsulation of organic and inorganic salts,
textural ingredients, enzymes, flavors and other functional
ingredients.
It improves heat stability, delay release in wet environments,
and/or convert liquid hydrophilic ingredient into free flowing
powders.
Spray cooling/chilling is typically referred to as ‘matrix’
encapsulation because the particles are more adequately
described as aggregates of active ingredient particles buried in
the fat matrix.

16. A spray cooled particle. The red arrows point to active
ingredient crystals sticking out of the fat matrix.

17. Spray Cooler Two-Stage, Counter current

18. Melt Extrusion
In melt-extrusion process forcing the core material,
which is dispersed in a melt carbohydrate carriers
through a series of die to form sheets, ropes or threads
of different dimensions.
Encapsulant ingredients like flavours can be added
either at the feed port of the extruder or to the molten
mass in the final zone using specialized pump systems.
The particular advantage of the melt-extrusion glass
encapsulated products is the ability to supply larger
flavour particles for visual impact in products.
Larger flavour particles will dissolve slowly and exhibit
some protection, controlled-release properties.

19. Melt extrusion flow diagram
1. Motor drive 1. Co-rotating screws
3 5 2. Solids Feed 2. Heating Jacket
2
3. Water 3. Transition zone
4 4. Water pump 4. Die
5. Flavour 5. Take off conveyor
6 6. Flavour 6. Cooling air
pump
8 9 10
12
1 7
11

20. Fluidized Bed
Fluidized bed technology is a very efficient way to apply a
uniform layer of shell materials onto solid particles.
It is one of the few technologies capable of coating particles
with different kinds of shell material like polysaccharides,
proteins, emulsifiers, fats, complex formulations, powder
coatings, yeast cell extract etc.
A number of food ingredients can be encapsulated by fluidized
bed coating such as ascorbic acid, acidulants for processed
meat and leavening agents.
Typical fluidized bed system can efficiently process particles
from 100µm to a few millimeters.

21. The Wruster Process
This technology is characterized by the
location of a spray nozzle at the bottom of
a fluidized bed of solid particles.
The particles are suspended in the
fluidizing air stream that is designed to
induce a cyclic flow of the particles past the
spray nozzle.
The nozzle sprays an atomized flow of
coating solution, suspension, or other
coating vehicle.
The technology can be used to encapsulate
solid materials with diameters ranging from
near 50µm to several centimeters.
Wruster Process can be used to encapsulate
vitamins, minerals, and functional food
ingredients.

22. Melt injection
This process is often referred to as the “Durarome”
process after the product trade name.
In this method sugar syrup or sugar-corn syrup is made.
Ingredients like flavour oils are then added to the hot
molten sugar, the pressure vessel is closed and high
shear mixing is employed to emulsify the flavour oil.
The hot sugar emulsion is expelled through fine orifices
into the chilled solvent bath (Isopropanol).
The product is obtained as fine threads free of surface
oil.
The property is especially important when citrus oils are
to be encapsulated.

23. Liposome Microencapsulation
• A liposome can be defined as an artificial lipid vesicle
that has a bilayer phospholipids arrangement with the
head groups oriented towards the interior of the bilayer
and the acyl group towards the exterior of the membrane
facing water.
• Liposomes are usually made of phosphatidylcholine
(lipid) molecules although mixtures of phospholipids can
also be employed to make liposomes.
• A unique property of liposomes is the targeted delivery of
their content in specific parts of the food stuffs.
• Liposomes can also be used to deliver the encapsulated
ingredient at a specific and well-defined temperature.

24. Simplified representation of molecular organization
of a liposome microcapsule in water

25. FOOD
VE TE RINARY ME DICINE
CH E M I CA L
B I OT E CH
I ND UST R Y
APPLICATIONS
P H OT O-
TE XTI L E
GR A P H Y
E L E CT - A GR I -
R ONI CS CUL T UR E
W A STE
T R E A T M E NT FEED

26. Trends in Microencapsulation Technologies

27. Opportunities for Dairy
Functional Food

28. Oils and Fats
Fish Oils
Long chain Omega-3 fatty acids reduce the risk
of heart disease, inflammatory and immune
disorders and have a role in early development.
Eicospentaenoic acid (EPA) and
docosahexaenoic acid (DHA) levels in milk can
be increased by incorporation of fish oils.
Incorporation of fish oil into food formulations
have had limited success mainly because of
fishy flavours coming through in the consumer
products.

29. Fish oils contd.
Microencapsulation extends the shelf-life of fish oil in
powder form increasing its versatility as a nutritional
ingredient in food formulations.
Fish oil powder produced by microencapsulating fish oil
with micellar casein in the form of SMP using
homogenisation and spray drying had acceptable taste
and modest shelf-life of 31 weeks at 4ºC.
Fish oil powder successfully incorporated into a number
of food products, including infant formulae, at levels to
satisfy the recommended daily intake of omega-3
polyunsaturated acids.

30. Vitamins
• Many of the vitamins are relatively unstable and their
ability to maintain activity in foods depends on pH and
reactions to heat, light, oxygen, oxidizing agents and
enzymes.
• Lipid soluble vitamins such as vitamin A, β-carotene and
vitamins D, E, K are much easier to encapsulate then
water soluble ingredients.
• Using microencapsulated vitamins in dairy products
reduces loss during storage.
• When cheese milk is fortified with vitamin D entrapped in
liposome higher levels of vitamin D were found in cheese
curd.

31. Vitamin losses and typical overages added to
compensate for losses during processing and
storage
Vitamin Product % Overages
recommended
β-Carotene Beverages 25-40
Dairy Products 25
Vitamin C Beverages 40-200
Dairy Products 50
Vitamin E Beverages 10-25
Dairy Products 5
Vitamin A Spray dried skim 10-25
milk
Vitamin D Spray dried skim 10-25
milk

32. Minerals
• Undesirable interactions between unprotected
mineral salts and components in milk can lead to
precipitation, colour and flavour problems.
• Encapsulating calcium salt (calcium lactate) in a
lecithin liposome it was possible to fortify 100g
soya milk with up to 110 mg Calcium. The soya
milk remained stable at 4°C for at least 1 week.
• Microencapsulated iron ingredients can prevent
off flavour development and maintain
bioavailability. Heat treatment and storage for 6
months did not result in decreased bioavailability
of Fe-fortified milk. (Boccio et al. 1997)

33. Probiotic Bacteria
A probiotic is a “live microbial supplement which
beneficially affects the host by improving its
intestinal microbial balance (Fuller, 1989).
Microencapsulation of probiotic bacteria can
improve its survival during storage.
Probiotic bacterial cells encapsulated in calcium
alginate provided protection in fermented frozen
dairy desserts (Shah and Ravula, 2000).
Survived at low pH of the fermented product and
in acidic conditions encountered in human
stomach and could be delivered in the intestine.

34. Flavour Encapsulation
Flavours consist of tens to hundreds of aromatic, volatile
organic compounds.
Microencapsulation can protect flavours, it can extend
shelf life and stability, control flavour release and provide
liquid flavours with a granular form.
The objectionable tastes and aroma of popular nutritional
ingredients like soy extracts, bitter herbs and omega-3
oils, can be masked by microencapsulation.
Microencapsulation can also be used to help to increase
the particle size of a flavour ingredient.
Liposomes have the ability to carry fat-based flavours in
their bilayer, as well as water soluble flavours in the core
of the vesicle.

35. Enzymes
• Microencapsulation of β-glactosidase in
liposomes can be used to act in vivo but protect
from acting on lactose during storage.
• Emulsifiers can be used as effective coating
material to microencapsulate lactase (Kwak et
al., 2001).
• Liposomes containing enzymes reduce the
ripening time by 30-50% as well as improve
texture and flavour.

36. Antioxidants
Ascorbic acid by entrapping it in a
liposome together with vitamin E is used
for protection of emulsion-type foods
(Reineccius, 1995).
Ascorbic acid with Vitamin E has
synergistic antioxidant effect.

37. Controlled Release
Controlled release of encapsulated ingredient at
the right place and the right time is gaining
significance.
Improve effectiveness of food additives,
broaden application range and ensure optimal
dosage.
The balance between entrapment and delivery
is determined by the selection and formulation
of the coating material.

38. Functions of controlled release in
foods
A substance in formulated food released upon
consumption but prevented from diffusion
during the series of operations in food
processing (e.g., flavours, nutrients).
A substance is released in a specific processing
step, but protected in preceding steps (e.g.,
leavening agents).
Immunoglobulins have potential in functional
food development as they afford protection
against gastrointestinal infection.

39. Mechanism of Controlled Release of
ingredients
Shefer and Shefer (2003)

40. Conclusion
Microencapsulation offers
alternative methods for the development
of functional dairy products. Its
suitability depends on the product, the
need for protection of food components
and timed release of nutraceuticals. It
can provide novel solutions to problems
encountered in the development of
healthy properties of foods.

41. Future Trends
New microencapsulation technologies are devsed and
invented by academics and researchers.
Microencapsulation offers alternate method for the
development of functional dairy food.
Near about 1000 and above patents were filed
concerning various microencapsulation processes and
their applications and over 300 of these patents were
directly related to food ingredient encapsulation.