Encapsulation Flashcards
define encapsulation
particles or droplets of an ACTIVE INGREDIENT are surrounded by coating or embedded in a matrix
other names for matrix
carrier, wall, shell, coating, external phase
core is also known as
active agent, payload, internal phase
what can encapsulation do? (purpose(6))
convert liquid to solid
capture volatile material
protect aroma compounds
controlled release
separation from food matrix
stabilise an emulsion
example of liquid to solid conversion
essential oils
use of capturing volatile material
flavour encapsulation
what do aroma compounds need protecting from
light, oxygen, degradation reactions
what is controlled release important for
stage of processing
consumption
advantages to encapsulation in food industry
superior handling, immobilisation and protection of active agent.
improved saftey
can modify properties
off taste masking
how does encapsulation result in superior handling
conversion of liquid to solid (Powder) might be dust-free, free-flowing, neutral smell, easier to dose
how does encapsulation protect the active agent
improved stability
less evaporation of volatiles
no degradation
how does encapsulation improve safety
reduced flammability
how can encapsulation modify properties
can change size, structure, solubility and colour
use of encapsulation in pharmaceuticals
off taste masking
objectives encapsulation in flavour delivery
protect aroma compounds
controlled release
what is a flavour emulsion
dispersion of flavouring material in aqueous solution
-oil in water emulsion
primary purpose of a flavour emulsion
deliver flavour to a product
-may result in cloudiness
-simple method of adding insoluble flavour into aqueous food system
major encapsulation processes used in the food industry
Spray drying
carbohydrate extrusion
encapsulation processesother than spray drying or
LIPOSOMES
freeze-drying
spray cooling/chilling
fluidised bed coating
pastilles, plating, prilling
what is carbohydrate extrusion
emulsion within a molten carbohydrate matrix
-hard candy like system: glassy state
capsule types
reservoir
matrix
poly- or multiple core
describe a reservoir type capsule
wall layer surrounding active agent
describe matrix type capsule
active agent is dispersed within carrier
-droplets embedded
describe poly- or multiple-core capsules
serveral reservoir chamber in one particle
-active agent is embedded and on surface
example of reservoir capsule
liposomes
complex coacervation
example of process used to geenrate matrix type capsule
spray drying
what is the most common encapsulation
matrix encapsulation
what is the most common method of encapsulation in the flavour industry
spray drying
describe the spray drying process
a solution is dried into a particulate powder by spraying the liquid infeed into a hot drying medium
spray drying steps
preparation of emulsion
atomisation
dehydration
how is the emulsion prepared for spray drying
prepare in feed
use a homogeniser
what is atomisation
turning the solution into fine droplets that dry quickly
what is dehydration
hot air is passed over particles in drying chamber and it moves into the cyclone where heavy particles fall and are collected
compare and contrast a simple reservoir vs a matrix
reservoir has a wall layer and core that contains the active agent
matrix has the active agent embedded in the particles
draw a single core encapsulation
yellow inner circle with blue outer circle
how are single core encapsulation acheived
-coacervation (cross linked polymers with opposite charges, usually a protein (gelatin) and hydrocolloid (acacia gum)
-liposomes (phospholipid bilayer)
what property makes phospholipids unique
emergent property in water to self organise in water to keep heads wet and tails dry
most common type of encapsulation
matrix
What are liposomes
microscopic vesicles containing a bi-layered phospholipid membrane structure
where is the active agent in a liposome
either in the aqueous compartment or attached to the membrane
application of liposome entrapment
pharmaceuticals and drug delivery
purpose of putting Vit C in liposome
enhances and facilitates absorption
green tea example of liposomes
put green tea catechins in liposomes and then added into cheese to improve nutritional profile
matrix/carrier requirements
needs to be the same phase as the continuous phase
-good emulsifying properties,
- ability to form good glass state
types of matrix/ carrier materials
polysaccharide
protein
types of polysaccharides used in matrix materials
gum acacia
maltodextrin
modified starcht
types of protien used as matrix material
casein
whey
gelatin
why is protein not often used in flavour application
protein binds flavour
what can the application of proteins as a matrix be used for
omega fatty acids
factors that influence the size of spray dried droplets
surface tension
viscosity
pressure drop
velocity of spray
what does the size of atomising droplets determine
drying time
particle size
what is the air inlet temp
150-220
what is the droplet temperature
never exceeds 100C
what is the air outlet temperature
50-80C
how do droplets stay cool
evaporative cooling
describe spray drying process in terms of flavour retention
droplets fall resulting in dehydration at certain point it enters glass transition state
-matrix in glassy state becomes impermeable (protecting active ingredient)
advantages of spray drying
low cost
good flavour load
equipment available
good protection of active agent
variety of matrix materials available
generate small particles
disadvantages of spray drying
small particles: reduces dispersibility, creates dust and clumps in water (glomerises),
secondary processes required to modify physical properties
not suitable for extremely volatile compounds
may have limited shelf life due to oxidation
what is flavour load
~20%
the portion of flavour active ingredient in final product
spray drying application
flavour materials
-aroma compounds
-essential oils
omega-3 lipids
-protection and delivery
-infant formula, fortified bread
bioactives
-curcumin, green tea
-peptides
probiotics
