packaging Flashcards
main purpose of packaging
protection
the passive role of packaging
protecting and marketing the product
active role of packaging
[processing, preservation, retaining safety and quality
primary function of packaging
minimise the transfer of heat and light
prevent gas transfer
prevent the physical damage
secondary function of packaging
facilitate distribution
other functions of packaging
communication
dispersing and dispensing
unitisation
packaging design considerations
functionality
energy/production efficiency
image
display
environment
cost
what is bulk density
amount of powder by weight that is present in a defined volume
filling, sealing and coding considerations
fillling
orientation
state
fragility
temperature
sealing
lid or seal
tamper-proofing, coding and labelling
secondary and tertiary packaging considerations
units/pack
diensions
loading effciency
closure
cost
strength
distribution methods
storage
environmental impact
type 1 plastic
PET
type II plastic
HDPE
type 3 plastic
PVC
type 4 plastic
LDPE
type 5 palstic
PP
polypropylene
type 6 plastic
PS
polystyrene
or
EPS
expanded polystyrene
type 7 plastic
other
what plastics can be recycled in NZ
1, 2, 5
what does packaging limit or control
light and heat
movement of substances
what is the barrier property measured by
permeability co-efficient- Pb
-measure of the packaging materials resistance to a permeant
degree of protection depends on…
chemical and physical properties of the packaging material
5 steps of mass transport
collision
adsorption
dissolves into polymer
diffusion
desorption
describe the 5 steps of mass transport
collision: contact of permeant with packaging
adsorption: attachment of product to packaging
dissolving: moves into the packaging
diffuse: moves out of the packaging
desorption: unattachment
factors affecting permeation
polarity
concentration or partial pressure
the thickness of the packaging material barrier
molecular packing
the surface area of the barrier
temperature and humidity
how does polarity affect permeability
the greater the difference in polarity the slower the rate of disolving will be
how does molecular packing affect permeability
orientation and amount of crystallinity can make it easier/harder for permeant to get through
the permeability of a polymer is influenced by
chemical composition
chemical structure
characteristics of HDPE
linear, crystalline structure
characteristics of LDPE
branched, less crystalline structure
characteristics of LLDPE
linear with many very short side chains
semi-crystalline
least permeable of LDPE, HDPE, LLDPE
LDPE
units of measurements for gas and water transmission rates
g m-2 d-1
what are gas/water transmissions rates used for
to calculate how many days before a product becomes unacceptable
equations for shelf life
O2 max/ OTR
the maximum oxygen gain / oxygen transmsision rate
aspects to consider with packaging
product
economy
packaging materials and machine
legislation
logistics
consumer
environment
marketing
packaging of a product affects its
flavour
integrity
shelf life
safety
cost
brand image
packaging classifications (5)
food packaging techniques
function
raw materials
use
management
raw material categories
type
source
types of raw materials
metal, glass, plastic, paper and cardboard
sources of raw materials
natural
synthetic
mixed
type of natural raw materials
metal
glass
wood
types of synthetic raw materials
polyethylene, polypropylene
PET, PVC
types of mixed raw materials
synthetic polymers from starch
categories of functions of packaging
active
passive
management categories for packaging
biodegradbale
recyclable
non-recyclable
if packaging is non-recylable what happens to it
burned for energetic recycling or landfill
types of food packaging techniques
vacuum
active
edible
MAP
aseptic
primary, secondary, tertiary
types of use of packaging
multi-use, single-use, edible
define active packaging
packaging material that interacts with the internal gas environment to extend the shelf life of a food
main APS in use
oxygen scavenging
CO2 production
water vapour removal
ethylene removal
ethanol release
controlled release of bioactive compounds
application of O2 scavenging
most food classes
application of CO2 production
most foods affected by mould
application of water vapour removal
dried and H2O sensitive foods
application of ethylene removal
horticultural produce
application of ethanol release
baked foods
application of controlled release of bioactive compounds
baked products, meat products, dairy products
important APS to remember
O2 scavenging
water buffering
taint removal
antimicrobial film
temperature abuse valve
mechanism of O2 scavenging APS
chemical reactions with reagents catergorised by high O2 affinity
compounds and materials used for O2 scavenging
Iron powder
photosensitive dye oxidation
ascorbic acid oxidation
ferrous salt
unsaturated fatty acids
level of residual oxygen in most packaging systems
between 0.1% (vacuum pack) and 2% (gas flushed)
how must dye photosensitisation packaging be kept
in the dark
examples of dye photosensitisation
tetraphenyl porphine dye in cellulose or silicon copolymer
what is BHA
butylated hydroxy anisole
-synthetic anti-oxidant that food producer are wanting to avoid using
most common reaction exploited in sachets
iron with oxygen
how much oxygen does 1 gram of iron react with
300ml of O2
explain the three layers of sheet scavnegers
outer-plastic
middle- O2 scavenging layer
inner- plastic
what must happen to sheets before use
activated by UV
does the light and temperature used to trigger packaging sheets matter
light - no
temp - yes
molecules used as CO2 scavengers
calcium hydroxide
iron based powder
soda lime
magnesium oxide
activated charcoal
other beneficial effects of CO2
-decreases microbial growth in fresh meat, poultry, cheese, and baked goods
-reduce the respiration rate of fresh produce
-overcome package collapse or partial vacuum caused by O2 scavengers
how can CO2 be generated from sachets and absorbent pads
moisture activated bicarbonate chemicals in pads and sheets
function of odour scavengers
remove trivial amounts of odour from lipid or plastic oxidation from packaging headspace
materials used for odour scavengers
activation carbon, cyclodextrins, vitamin E
how can ethylene absorbers be used
ethylene from fresh produce can be removed extending the shelf life
function of antimicrobial packing systems
reduces rate of growth in spoilage or pathgenic microorganisms in the ocntained food
6 ways to construct antimicrobial packaging
within the packing material
plated surface facing food
two-layer packing one for protection and one for controlled release of anti-microbial
sachet with antimicrobial
edible packaging
factors affecting efficacy of anti-microbial
extrusion and solvent casting
extrusion temperature and specific mechanical energy
solubility and reactivity of agent
food pH
release profile
describe the three types of release profiles and which is desired
unconstrained
slow diffusion
membrane/ reservoir
-3rd is most wanted cause it stays above min conc for most tim
classes of smart packing systems
mechanical and chemical
smart packaging can (3)
track the product
sense the environment inside and out
inform customer, retailer or manufacturer
how can smart packaging heat or cool food
using exothermic reactions
-calcium or magnesium oxide with water
what are microwave susceptors
packaging that reflects microwaves and helps ensure even heating
Examples of indicator packaging
RFID: radio frequency identification
time and temp: threshold indicators
what indicator turn pink in low O2/ high ethylene
ethylene oxide, ripeness indicator
