Microencapsulation for the improved delivery of bioactive

compounds in foods

Speaker: Manoj Solanki PhD 1st Year Dairy Chemistry NDRI, Karnal

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.

(Arneado, 1996)

Why microencapsulation ?

Protection

Controlled release

Enhance acceptability

Improved delivery

Pictorial representation of the encapsulation process

M. Popplewell (2001)

Methods of encapsulation

Coacervation• Co-crystalization

Molecular inclusion• Spray drying

Spray cooling/chilling • Extrusion

Fluidized bed• Melt injection

Liposome

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.Flavour oil

Fish oils

Vitamins

Nutrients

Enzymes

Preservatives

Coacervation

Co-crystallization

Supersaturated solution

Transformation or crystallization

Flavour material

Syrup blend

Microsized crystallization(incorporated product)

Drying milling and screening

Functionally crystallized product

Concentration

Agglomeration

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.

Spray-drying

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 cooling/chilling

‘matrix’ encapsulation because the particles are more adequately described as aggregates of active ingredient particles buried in the fat matrix

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.

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1. Motor drive

2. Solids Feed

3. Water

4. Water pump

5. Flavour

6. Flavour pump

7. Co-rotating screws

8. Heating Jacket

9. Transition zone

10.Die

11.Take off conveyor

12.Cooling air

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.

The wruster process

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.

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.

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

Morphology of encapsulation

(Augustin et al, 2001).

Use of encapsulation

Food

Bioactive

compounds

functional foods

Technological

challenges

Microencapsulation is a

useful tool

Use of bioactive compounds

Bioactive

compounds

Flavour

Colour

Preservation

Health benefits

Stability of the bioactive compounds

during processing and storage

Microencapsulation technologies used for bioactive food ingredients

Microbial products

Probiotic bacteria are ‘defined, live microorganisms which, administered in adequate amounts, confer a beneficial physiological effect on the host’.

These bioactive ingredients have been at the forefront of the development of functional foods, particularly in dairy products,

Probiotics

Size (typically between 1 and 5 μm diameter)

Must be kept alive.

Microencapsulation

Spray-coating

Spray-drying

Extrusion

Emulsion

Gel-particle

Spray-coating methods for the microencapsulation of probiotics

Fermentation --- concentration--- freeze-drying ---granulation

lipid-basedwaxes, fatty acids and oils

Protein-based

gluten and casein

Carbohydrate-based

cellulose derivatives, carrageenan and alginate

Coating Material

Gel-particle technologies for the microencapsulation of probiotics

(Claude and Fustier, 2007)

Non-microbial products

Microencapsulation technologies used for bioactive food ingredients

Spray-drying

Oil-based vitamins,fatty acids

Spray-chilling and liposome

retinol, omega-3 fatty acids, yeasts, enzymes

The delivery of bioactive ingredients into foods and to the GI tract

(Claude and Fustier, 2007)

Cont…

Beneficial effects of probiotic microencapsulation.

Cont…

Spray-chilling and fluidized-bed coating are the most popular methods for encapsulating water-soluble vitamins (e.g ascorbic acid), whereas spray-drying of emulsions is generally recommended for the encapsulation of lipid-soluble vitamins (e.g. b-carotene, vitamins A, D and E) (Gouin, 2004)ME promotes the delivery of vitamins and minerals to foods mainly by preventing their interaction with other food components;

for example, iron bioavailability is severely affected by interactions with food ingredients (e.g. tannins, phytates and polyphenols).

Additionally, iron catalyzes the oxidative degradation of fatty acids and vitamins.

Beneficial effects of microencapsulation.

Consumption of food enriched with microencapsulated fish oil obtained by emulsion spray-drying was as effective as the daily intake of fish oil gelatine capsules in meeting the dietary requirements of this omega-3 long-chain fatty acid .

(Champagne et al, 2006)

ME is usually used to mask unpleasant flavours and odours, or to provide barriers between the sensitive bioactive materials and the environment (food or oxygen).

Average daily weight gain in cat by supplemented with P.E.P. MGE

The delivery of microencapsulated iron to the GI tract

ME alone in promoting the survival of probiotics introduced into biscuits, frozen cranberry juice and vegetable juices.

(Weiss et al., 2006)

ME can also serve to co-entrap prebiotics (i.e. nondigestible food ingredients that can beneficially affect the host by selectively stimulating the growth and/or the activity of bacteria in the gut), raising the possibility of using ME to deliver multiple bioactive ingredients.

Case studies

Bioactive peptides, such as bacteriocins, are also candidates for co-encapsulation; they could enhance or complement the antimicrobial activities of the probiotic bacteria, especially if the health target is protection against diarrhoea.

(Arneado,2008)

By encapsulating calcium lactate in lecithin liposomes, it was possible to fortify soymilk with levels of calcium equivalent to those found in cow’s milk , while preventing undesirable calcium-protein reactions.

(Augustin et al., 2009)

As with probiotics, the co-encapsulation of vitamins and minerals could be beneficial.

Ocean Nutrition Canada Using a proprietary microencapsulation technology, ONC provides the food and dietary supplement industry with a microencapsulated powdered fish oil with the highest concentration of bio-available Omega-3 in the market place. ONC’s process enhances shelf life and bio-absorption while maintaining the taste and texture of the products.

(www.ocean.nutrition.com, 2011)

Institute Rosell/ Lallemand’s encapsulated probiotic bacteria products for use in dietary supplements and functional foods is based on a modified fluidized-bed encapsulation process. Clinical testing has shown the encapsulated probiotic bacteria have 100 percent recovery rate, compared to the standard industry rates of 25 to 50 percent.

(www. lallemand.com, 2011)

ME could be useful in helping to deliver bioactive ingredients both to the food matrix itself and to the GI tract

ME has primarily served for the delivery of bioactives into the matrix and, as yet, has not been fully explored for more efficient delivery in the GI tract

Conclusion

ME might even be used to create particles that clearly show consumers that the bioactive ingredients are present in the functional foods, thus promoting marketing strategies for product differentiation.

Another area that is likely to see intense research activity in the future is the use of co-encapsulation. In this regard, many emulsion and spray-coating technologies offer significant opportunities for the co-encapsulation of various hydrophobic and hydrophilic bioactives.

Thank You