Food packaging

2. Food packaging is packaging for food. A
package provides protection, tampering
resistance, and special physical, chemical, or
biological needs. It may bear a nutrition facts
label and other information about food being
offered for sale.

3. packaging preserves food and prolongs its
shelf life by protecting it from bacterial
damage, moisture and insect attack.
Some packaging preserves food
for a very long time, such as tins.
Today, due to the way we shop,
packaging also prevents
tampering, provides information and
attracts customers.

4. General requirements of food packaging:
 Nontoxic
 Prevent contamination from microorganisms &
environmental toxicants
 Barrier to moisture, oxygen, UV light & odors
 Provide resistance to physical damage
 Be tamper-resistant or tamper-evident
 Easy to open
 Have dispensing & resealing features
 Be disposed of easily
 Meet size, shape & weight requirements
 Have appearance, printability features
 Have low cost
 Be compatible with food
 Be transparent

5.  The objectives of packaging include:
• prevent physical damage, e.g. from
knocking, shaking or crushing;
• prevent contamination from micro-
organisms, pollution or vermin;
• protect against dehydration or
dampness;
• protect the product’s nutritional and
sensory characteristics;

6.  contain the product and keep it intact.
 liquid products do not leak and that dry materials,
such as flour, do not spill out.
 Well protection form damage
 keep the product in peak condition;
 help to increase a product’s shelf life.

7.  To protect a product from damage or
contamination.
 To keep the product together, to contain it (i.e.
so that it does not spill).
 To identify the product.
 Protection during Transport and Ease of
Transport.
 Stacking and Storage.

8.  Aluminium container
 Aluminium foil
 Paper
1. kraft paper
2. coated paper
3. brown paper for packing and wrapping
4. greaseproof
 Plastics
1. Polypropylene
2. Polyvinyl chloride
3. Polystyrene
4. Polyester
 Cellulose film
 Glass
 laminates

9.  As related to food packaging is chemically inert.
 The principle limitation is susceptibility to breakage
which may be from internal pressure , impart
thermal shock.
 Preparation: soda ash ,lime stone and other material
moulded by heating to about 1500 Celsius and send
to oven to impart toughness.
 The average life of a glass water in a soft drink
industries is 4-6 years
ADVANTAGES:
1. free of corrosion
2. Glasses impermeable to both gas and liquid
3. odourless
4. permitting full vision of package product and give
the feeling of cleanliness .

10.  Mechanical impact strength
 Resistance to thermal shocks.
 Thermal endurance
 Resistance to internal pressure.
 Resistance to collapse
 Dimensional conformance of the finish
 Dimensional conformance of the body.
 Capacity
 Chemical durability
 Visual appeal.

11.  VISUAL DEFECTS:
1. It is examined against a glare-free illumination
from a suitable light source.
 CRITICAL DEFECTS:
1. cracked or broken glass
2. choked bore
3. internal fins
4. flanged fins
5. over press
6. Split finish
7. Channelled and wrapped sealing surface
8. Shifted finish
9. Rocker bottom

12.  MAJOR DEFECTS:
1. stones
2. seeds
3. cords
4. blisters
5. rough sealing surface
6. crizzle
7. oil marks
8. bad distribution
9. Deformation
 HYDROSTATIC PRESSURE TEST:
1. Bottles are filled with water and pressure is
applied by a pump.
2. Pressure is raised to a specified limit at which
the container should not break

13.  Low alkali glass like “neutral "or “boro
silicate "is used.
 Glasses are grouped into various types ( 1 to
5) according to their chemical durability i;e,
extractible alkalinity.
 Alkalinity is measure by treating it with a
standard acid solution.
 The user should be more concerned with the
inside surface of the container

14.  Hot End Process:
1. It employs high amounts of heat to produce
and shape a glass container. A furnace is first
used to mould molten glass(glass feed
stock).
2. calcium oxide,lime,silica,Soda-lime glass
and small amounts of aluminium oxide,
ferric oxide, barium oxide, sulphur trioxide,
and magnesia for about 5 percent of soda-
lime glass.
3. Before melting, cullet (recycled glass) is
added to the stock, accounting for anywhere
between 15 and 50 percent of the final glass
composition.

15.  After stock has been fed into furnace temp. is
increased to 1675°F.
 Next, one of two method forming methods is
applied press-and-blow or blow-and-blow

16.  ANNEALING:
1. Once formation is complete, some bottles may suffer
from stress as a result of unequal cooling rates.
2. An annealing oven can be used to reheat and cool
glass containers to rectify stress and make the bottle
stronger.
 COLD END PROCESSES:
1. In this stage, the bottles or glass containers are
inspected and packaged.
2. Inspection is often done by a combination of
automated and mechanical inspection, to ensure
the integrity of the final product. Common
faults include checks, stones etc.which are
important to catch because they can
compromise the component.

17.  Closures are devices and techniques used to
close or seal a bottle, jug, jar, tube, can, etc.
Closures can be a cap, cover, lid, plug, etc.
 Metals and plastics are basically used for their
manufacturing.
 Fabricated from tinplate, steel plate or
aluminium.
 Many containers and packages require a
means of closing. It can be a separate
device or seal or sometimes an integral
latch or lock.

18.  PURPOSE OF CLOSURE:
1. Keep the container closed and the contents
contained for the specified shelf life until
time of opening
2. Provide a barrier to dirt, oxygen, moisture,
etc. Control of permeation is critical to
many types of products: foods, chemicals,
etc.
3. Keep the product secure from undesired
premature opening
4. Provide a means of reclosing or reusing the
container
5. Assist in dispensing and use of product
6. Allow reasonable ease to open the
container by the intended user.

19.  METAL CLOSURES:
Fabricated from tinplate, mild steel
plate or aluminium, they take different
forms depending upon their needs of usage.
They have EOE (easy opening ends)
 CROWN CAPS:
Used mostly for beverage bottles and
other processed products. These are
Shallow metal caps that are crimped
into locking position around the head
of the bottle.

20.  LUG CAPS:
They seal the vacuum inside the
headspace of the glass bottle,
they require puncturing to open it.
Also known as twist-on twist-off
caps. Used for jam bottles and
other similar products.
 PLASTIC CLOSURES:
They are produced from
polypropylene and are injection
moulded .They allow venting out
excess gas pressure to prevent
bursting.

21. Corkers
1. Corks are mainly used to close wine bottles by
pressing them into the neck under considerable
pressure while at the same time squeezing them, to
reduce the diameter so that they will enter the
bottle neck.
2. The corks are wetted before use so that they will
slide more easily into the bottle neck.
3. they are soaked in a solution of sodium met
bisulphite to avoid contamination to avoid
contamination.
 Plastic hinge-open snap-shut closures
1. They are becoming increasingly common for liquid
products that are opened and closed several times in
use.
2. Simple hand-operated presses are available to fit
this type of closure.
3. Common applications include cooking oils,
sauces and fruit toppings.

22. DISPENSING DEVICES:
1. Dispensing device range from flip top
caps to cans.
2. Used to dispense measured dosages.
3. In aerosol sprays, specially designed valve
is used for uniform spraying having a
definite particle size.
4. They are designed to ensure
complete emptying of the
container and avoiding
wastage particularly for
high value products

23. The design of the dispensing device depends
on the following:
 Viscosity or flow properties of the product
 Value of the product
 Accuracy of the output required
 Nature of the product

24.  BAG-IN BOX SYSTEM:
1. In packaging, a bag-in-box or BiB is a type
of container for the storage and
transportation of liquids.
2. usually made of several layers of metallised
film or other plastics, seated inside a
corrugated fibreboard box.
3. Used to dispense bulk supplied condiments
such as ketchup or mustard in the
foodservice industry specifically in fast
food outlets.

25.  it is inexpensive.
 The bag allows a contents of 1.5–
1000 litres, so that less packaging or
labelling is required.
 The material it is made from is
lighter than the other plastic
alternatives providing it with a
better carbon footprint.

26.  Cans were traditionally made from tin plate sheet,
but now more commonly aluminium is used (for
drinks).
 The inside of the can is often sheet coated with
lacquers to prevent the cans rusting and reacting
with the contents, especially acidic foods.
 The effectiveness of tin coating depends upon its
thickness method of applying (electrolytic plating
,composition of the under living steel) types of
food and other factor(temp., pressure, humidity
etc.)

28.  FULL TOP CANN- mostly made of Al+2 which has a key opening
device it contains a lacquer waiting for packaging the acidic foods
 PASSIVATION-external surface of a cann are treated when canns
are held in or exported to warm humid areas ,dis treatments
prevents resulting of canns .
 SLIP OVER LID- This is the sanitary opening cover is reversible ,air
tight and temper to sealing can be done .
 COFEE CANNS- guiding a plastic lid convenient to open .
 COLAPSE CANNS- bulkiness and transportation can be achieved at
low cost by delivering fatten cann bodies. They are reformed and
bottoms are attached prior to filling.
 AEROSOL CANNS-(pressurised cans) pressurised food packages or
aerosol packages are two types-

29.  A- Aerosal type-(foam)
 B-Wax spray – non aerated container ,(liquid)
dispenses material as a foam like whipped cream
and wet spray non aerated container which
dispenses material as a liquid for packaging in
aerosol cans .
 FOIL LAMINATED FIBRE CANNS -lighter in weight
,and lower in price example-fruit juice or juice
concentrates.
 UNIT PACKED CANNS –has both top and bottoms
made of Mattel's which are seamed (sealed) of
any type of martials ex-card board and are not
made for reuse metal provide easy stacking .

30.  The testing methods include:
1. Visual inspections for printing and
manufacturing defects
2. Dimensions inspection
3. Ready container height, capacity or over
seam diameter.
4. Air pressure test for leakage
5. Handle pull test
6. Crush resistance test
7. Product compatibility.

31. Food packaging uses a wide range of both rigid and flexible
plastic materials including:
 polythene – low density is used as a film wrapping,
resistant to water. High density is used for ‘boil-in-the-
bag’ products;
 polyamide (nylon) – provides a very good barrier to
oxygen, so used for vacuum packaging, especially for
foods containing fat (which can be susceptible to
oxidation).
 Type 1 – PET is the most commonly used one (water
containers); APET (fizzy drinks); CPET is heat resistant
(oven ready-meal trays)

32.  Type 4 – LDPE (plastic bags and bin liners)
 Type 5 – PP (margarine tubs and microwaveable
meal trays)
 Type 6 – PS is polystyrene (yoghurt pots, plastic
cutlery, egg cartons, vending cups and burger
cartons)
 Type 7 – other plastics that do not fall into any of
the above categories (melamine and non-
breakable plates and cups).
 Type 2 – HDPE (milk and detergent bottles)
 Type 3 – PVC is banned in some countries (food
trays, cling film, bottles of squash, water and
shampoo)

33. Injection moulding Here grains of
plastic polymer are heated by a screw in
a moulding machine and then injected
under high pressure into a cool mould.
The method is mainly used for wide
necked containers and lids.
Injection blow moulding- Polymer is
injection moulded around a blowing
stick and, while molten is transferred to
the blowing mould. It is then blown into
shape by compressed air.

34.  Extrusion blow moulding- In this method a
continuously extruded tube of softened
polymer is trapped between the two halves of
a mould. It is then inflated by compressed air
into the mould.
 Stretch blow moulding- A shape is prepared
by either injection or extrusion moulding. It is
then re-heated, which causes the molecules of
plastic to 'line up'. This gives a glass clear
container of greater strength which has good
barrier properties to gases and moisture over a
wide temperature range.
 Blow moulding : is similar to glass bottle
making and is used as a one or two stage
process to make bottles, jars and pots

35.  Excellent barriers against microbes and dirt.
 Eg. Of laminates include: polymer coated
cellofin , metallic foil , polythene combined
with aluminium foil.

36.  Cellulose films are used for different types of
food packaging, because they have a range of
characteristics such as different degrees of
moisture proofing.
 Some cellulose films are heat sealable.
 They can be used, for example, as window
patches in cartons.

37.  Often used for printing containers.
 Made from natural and occasionally synthetic
fibrous material being the precipitate of its
suspension in water.
 coated with waxes,raisins,plastics, laminates of
aluminium to improve vapour and gas permeability.
Types of packaging paper
1. Grease proof paper
2. Kraft paper
3. Pouch papers
4. Cardboard

38.  MANUFACTURING OF PAPER:
 Raw material preparation
 Pulping
 Bleaching
 Stock preparation sheet formation
 Consolidation
 drying
 Finishing
 Pulping methods can be divided into :
1. Chemical pulping
2. Semi-chemical pulping
3. Mechanical pulping

39.  Only required in those grades where higher
brightness level is desired.
 Common bleaching chemicals used are-
chlorine and hypochlorite.
BRIGHTNESS OF DIFFERENT PULPS
Type of pulp Brightness (%)
UNBLEACHED SULFATE 20-45
BLEACHED SULFATE 70-85
UNBLEACHED SULPHITE 50-65
BLEACHED SULPHITE 75-85
SPECIALLY PURIFIED PULPS UPTO 90-94
GROUNDWOOD 55-60

40.  Suspension of the fibre from its suspension in
water
 Removal of water occurs by gravity and then
vacuum is applied.
 Next, in the press section 42% dryness is removed
 Followed by water removal in a battery of steam
heated drying cylinders.
 Lastly it is passed through a calendar to remove
uneven surfaces

41.  Grease proof paper:
1. Use in packaging of butter, margarain etc.
 Kraft paper:
1. Also know as unbleached heavy duty paper.
2. Mostly used for printing containers.
 Pouch papers:
1. Made up of special kind of laminated paper.
2. Smooth surface
3. Used for packaging of coffee,dehydrated
soups,milk foods etc.

42.  Cardboard:
1. Made of sulphate pulp for packing ice-
cream etc.
2. The pulp gives it water and oil
resistance.
3. Other types include glazing type paper
made of long wood pulp for imparting
physical strain.