Packaging of milk and milk products

Introduction

Packaging is the technique of using the most appropriate containers and components to protect, carry, identify and merchandise any product. It constitutes a vital link between the manufacturer and eventual consumer for the safe delivery of the product through the various stages of manufacture, storage, transport, distribution and marketing. In order to deliver fresh, sound and convenient form of milk and to minimize the losses protective packaging is necessary to withstand the hazards of climatic changes, transportation, handling etc. The criteria by which a package is judged are usually the following:

1. It must protect and preserve the commodity from the time it is packed to the point of consumption.

2. It must be suitable for the chosen selling and distribution system.

3. It must be attractive to the consumer, easy to open, store and dispose.

4. It must cost no more than the market can bear.

Definition

Packaging means placing a commodity into a protective wrapper or container for transport or storage.

Functions

Package has a three fold functions of containing, protecting and merchandising:

1. To contain the product

Package should be large one with proper constructional features so as to avoid leakage and spoilage. It should be as compatible as possible with the product and finally it should have enough strength to withstand handling, transportation and storage hazards.

2. To protect the product

Protection of the product against contamination or loss and damage or degradation due to microbial action, exposure to heat, light, moisture and oxygen, evaporation etc.

3. To help in selling the product

The shape of the package should be favourable to dispensation and reclosure, and to its disposal and reuse.

Present status of the packaging industry

In developed countries packaging industry has met tremendous advances. With newer marketing systems like super markets, self services stores etc packaging technology in these countries has risen to great heights. Newer and better packaging materials, development of packaging machinery and appliances have all advanced in an integrated manner. In developing countries like India, packaging is still in its infancy.

Packing materials and forms

Following are the packing materials used

A) Materials

1. Paper and paper based products

The papers are used commonly in the form of wrappers, cartons, boxes, bags etc. The merits of paper are its relative weightlessness, low cost and easy disposal, its availability in various types etc while disadvantages are it is of low tear and wet-strength (unless treated or coated).

2. Plastics

A wide variety of rigid plastics can be used as thermoformed, such as bottles, cartons etc. Flexible plastic packaging films are used as wrappers/bags/pouches. These are of two types namely low polymers which includes cellophane (coated with polyethylene) and high polymers which includes polypropylene, polystyrene, polyester etc. The merits of rigid plastic containers are its low cost and ease of fabrication, and demerits are lack of product compatibility, plastic deterioration, lack of resistance to high heat and fragility at low temperatures.

3. Aluminium foil

Aluminium foil has good barrier properties, is greaseproof, non-sorptive, shrink-proof, odourless and tasteless, hygienic, non-toxic, bright in appearance etc. The common thickness of this medium for use in products is 0.012 to 0.015mm. Disadvantages are it has low tear strength, is attacked by certain strong alkalis and acids, and it does not heat-seal by itself.

4. Timber

Timber is used in the form of box, tub or barrel. It should be free from odour, have an attractive appearance and necessary mechanical strength. It may be treated with casein-formalin, or spread with paraffin-wax or plastics, to make it more water resistant and prevent the passage of the timber-taint to butter.

5. Glass

Glass may be transparent or opaque. Used in the form of bottles, jars, jugs etc. Glass has the merits of strength, rigidity, and an excellent gas and water vapour barrier while the disadvantage is of heavy weight and fragility.

f) Tinplate

This consists of a thin sheet (0.025mm thick) of mild steel coated on both sides with a layer of pure tin. Tinplates have the merits of good strength, excellent barrier properties while the demerits are of high cost, heavy weight, difficult reclosure and disposal. It is used in the form of cans.

g) Laminates

Laminations are made for following reasons: To further strengthen the film material; to improve barrier properties; to improve grease-resistance; to provide a surface that will heat-seal; etc. Some typical laminates are paper polythene, cellophane-polythene, and polyester-polythene.

2. Forms

1. Bottle

The glass bottle still continues to be the most frequently used package for milk in the world. Advantages:

v Light in weight, easy to handle and no danger of breakage.

v Lower distribution cost.

v Effective sales message can be printed.

v No exposure to sunlight.

v Tamper-proof.

v Filling machinery compact and occupies less space.

Disadvantages:

v Difficult to remove cream.

v Regular supply of special paper/film necessary.

v Difficult to open.

v In some of the cases leakage may occur.

v Costs higher per unit milk distributed.

1. Cartons

Cartons play a significant role in the bulk packaging of milk. Cartons are commonly used for liquid, frozen and coagulated milk products. They are commonly available either as performed containers or as precut blanks ready to be formed into containers.

2. Cup

It is made up of paper with wax or plastic coating on the inside. It is used for frozen and coagulated products.

3. Sachet/pouch

The bags may be formed from either a reeled or flat film. Generally it is a form/seal system. Ultra-violate light may be used to sterilize the film.

4. Can

This is a commonly used for all types of solid, semi-solid and powdered products. Recently aluminium cans have been introduced. Cans are the most convenient for gas packing.

5. Barrel

Commonly made of wood and coated with wax on inner surface. Used for bulk packaging of sweetened condensed milk, semi-solid buttermilk etc.

6. Collapsible tube

It is made up of aluminum and lacquered on the inner side. Its merits are low cost, light weightedness, is of handling, product protection etc. It is used for semi-fluid products such as sweetened condensed milk, processed cheese spread etc.

Standardization in packaging

With rapid industrialization and improvement in transportation methods, packaging standards would have to be reviewed periodically so as to effect an economy in packaging-which is so vital, particularly in international trade