2. Milk is one of the basic food stuffs and
from it have been derived a variety of
processed foods which are known as dairy
products
Whole milk is a complex physicochemical
system consisting of a water solution of
salts, lactose and lactalbumin
Proteins are colloidally dispersed in the
water solution and milk fat solids are
present in a partially emulsified suspension
3. WHY WE NEED PACKAGED MILK????
Risk of pathogens in open milk due to surrounding
environment and unhygienic grazing conditions
Risk of bacteria inside and outside the udder during milking
Improper sanitization while milking manually or mechanically
Unsterile storage and transportation equipment
5. PACKAGING MATERIALS USED
FOR MILK
1. Glass
2.Paper board
3.Plastics
4.Milk cartons
5.Rigid plastics
6.Returnable plastic bottles
6. 1. GLASS
Until 1950, almost all milk was packaged in glass bottles
The increase in supermarket shopping and the decrease in home
delivered milk have served to lessen the usage of glass milk bottles
Glass milk bottles originally were round, tapering to a rather
wide mouth with a thick flange
The move to a squared a body saved considerable space in the
home refrigerator
Finland milk is packed in brown glass to filter out harmful light
Bottles closures are formed from aluminium foil , HDPE , PP , and
paperboard
Most closure are applied by automatic machinery at high speeds
Printing is applied prior to use
7. WHY MILK PACKAGED IN
GLASS??
Transparent
Strength
and
rigidity
Water and
gas barrier
Thermal
shock
resistance
Cheap
cost
Inertness
to chemical
substances
100%
recyclable
8.
9. 2. PAPER BOARD
The introduction of wax coated paperboard captured the
milk market in the late 1940s
The outer surface had a cloudy , unattractive appearance
Although a few PVC Coated cartons were tried, the
introduction of PE coated paperboard in the early 1960s
solved nearly all the problems inherent in milk packaging
It was disposable, clean looking and functional
10. An all plastic milk bottles is light weight and tougher than its two
competitors.
Reclosure is more sanitary than the tear open cartons
Pigmentation can be used to help screen out light
Disadvantages include difficulties in connection with printing,
labeling and various decorating techniques
The basic materials in general use for an all plastic milk bottles are
PE, PS, and more recently polycarbonates
3. PLASTIC
11. Reasons to shift from glass to HDPE containers
Heavy weight
It occupies more space during transportation and storage
Fragility
Due to fragile nature it needs more protection due to external hazards
Cost
Though material cost is less, it increase the cost of transport and storage which
leads to more fuel consumption
Material consumption
For packaging of 100 ml milk we need 500g of glass material
Effect of light
Light damages the nutritive components of milk
Chemicals
The effect of chemicals for washing the bottle leads to environmental hazard
12. Many different cartoning lines exist and varying carton designs are
used
A unique system is the Perga carton patented by Jagenberg
company in Germany
The Perga cartons consists of a two piece container. It is widely
used in Australia
In US , one of the major packets used is the pure-pack
This is used by the dairies as precut blanks which are formed, filled
and sealed on one machine
Paperboard cartons sales are in pint (0.47 liter), half pint (0.24
liter) and half gallon sizes (1.9 liters)
Most attempts to design gallon (3.78 liters) paperboard cartons fail
because of manufacturing costs or because the handles don’t
support the weight
4. MILK CARTONS
13. Preformed
Preformed cartons are supplied to the dairy in a fully erect form
and ready for filling
Eg:- Perga carton
Precut
In a precut carton system, printed, coated paperboard blanks are
supplied in a knocked down shape
The final carton is set up, formed , filled, and sealed on one
machine
Eg:- pure pack
Postformed
post forming uses roll stick, forms, fills and seals in one
continuous operation
The system may use PE or foil laminated paper
The zupack is a rectangular block while tetra packs are
tetrahedron shaped
14. Reasons for selecting carton as milk
packaging
Light weight
Made from renewable raw material
Increase distribution efficiency
Hygienic
One-way containers
Aseptic type, doesn’t require refrigeration
Easy to dispose off
Recyclable
15.
16.
17. Once milk packaging encountered a problem that, caps did not fit
satisfactorily. So capping and filling procedures must be modified in
order to introduce plastic bottles
Metal screw caps then appeared and were capable of preventing
milk spoilage
The cost of the metal cap was high and its use was restricted in
several countries
A recent innovation in closure devices is a plastic top made of PE
with a diaphragm
The cap is applied to the bottle and the diaphragm is in the center of
the cap
When the diaphragm is depressed the caps expands causing a tight
fit
It is tamper proof and may be produced at high speeds
5. RIGID PLASTICS
18.
19. 6. RETURNABLE PLASTIC BOTTLES
The higher competitive cost of an all plastic bottle
compared to paperboard and glass had led to the
development of the returnable plastic bottles
Polycarbonate returnables are receiving noticeable
interest
20. NEW TRENDS……………..
1.FLEXIBLE PLASTIC POUCHES
• Liquid milk also may be packaged in plastic film or laminated pouches
• Pouches offer economy, compact storage and ease of disposal
• Disadvantages include the need for support and an unconventional appearance
• Since clear plastic does not offer adequate shelf life, an opaque laminate is required
• Most all plastic film pouches for milk are prepared from two ply, LDPE lay flat tubing
• The outer ply is white and the inner ply is black to protect the milk from UV
degradation
• The lay flat tubing is made by extruding two PE resins through a coaxial die and then
passing the two films through a second dye to produce a 0.001 cm laminate
• On the packaging machine the tubing is sterilized by UV irradiation, cut to the
desired length, sealed on the bottom to form a pouch, filled and heat sealed at the
top to close
21. REASONS FOR SELECTING
FLEXIBLE POUCHES………
Cheapest in the world
Easy to handle
Occupies less space
Convenient
Recyclable
Use lowest amount of packaging material
Bottles don’t need to be collected, washed, refilled and
redistributed
22.
23. 2. PAPER BOARD PLASTIC LINER
• In recent years, a bag in box concept utilizing a LDPE bag in a corrugated
container has become popular
• Both the bag and box are completely disposable
• The inner ply consist of either single or double ply 0.005 cm PE
• A spout is heat sealed into the bag and a plastic valve may be added for
dispensing purposes
• The bag collapses in use as the level of liquid falls
• The corrugated fiber board container is printed and used as the outer
package
24. 3. ASEPTIC PACKAGING
• Aseptic or long life milk was originally introduced in Sweden in the
early 1960s
• Originally called the tetra pack system , it utilizes a laminate pre
sterilizer and a filling environment heater
• Aluminium foil is an integral part of the flexible laminate in order
to provide a barrier against light and gas
• Cows milk is preheated to 73.8- 85 then rapidly raised to 140.5-
148.8
• It is held at the latter temperature for 2-4 sec and then suddenly
cooled by flashing into a vacuum chamber
• It must be packaged under completely sterile conditions
• No refrigeration is necessary for at least 3 months
• If kept under refrigeration, a shelf life of up to 1 year is possible
25.
26. Milk in tetra pack……………..
Is ultra heat treated
Is aseptically packed
Light and easy to transport
Preserves maximum nutrients
Has a longer shelf life
Need not be refrigerated
100% recyclable
27. 4. CANNED MILK PACKAGING
• Sterilized canned milk is produced by using lacquered
tinplate cans which have a special seam stronger than
a conventional can
• They must be able to withstand the stresses imposed
by high temperatures used to sterilize the contents