PRODUCTS BEING PACKAGED IN 'ASEPTIC' PACKAGES WORLDWIDE

Dairy	Fruit based	Alcoholic	Others
Fermented milk, yogurt, yogurt drink, Eggnog, custard pudding, icecream mix, non-dairy whitner, whipping cream, process cheese spread, dietary supplements	Papaya, Watermelon, mango, guava drinks, soups, nectars, sauces, catsup, soy chocolate	Saki, wines, syrups, mixed fruit, soy-based drinks, soy milk	Sugarcane juice, lemon juice, herbal tea, lemon tea, corn oil, tomato juice, coffee chrysanthemum tea, jasmine tea, mineral water

Aseptic Blow Moulding :

Aseptic Blow Moulding is a process where the bottle is extrusion blow-moulded in a commercially sterile environment with highly modified equipment. In many cases, the product filler is combined with the blow moulder. In general, modifications to the equipment include the use of special stainless steel and plated materials throughout. The moulding/filling area of the machine is enclosed in a cabinet. Sterilized air with positive pressure and laminar flow characteristic is maintained inside. All internal surfaces, passage-ways, hoses, blow pins, valves and so forth are sterilized with special "clean-in-place" fixtures. Once the process begins, nothing can be touched with the human hand. Although bottles as large as 10 litres have been aseptically moulded, the process is generally used for bottles and vials of small sizes.

Flexible Packaging Systems :

The use of flexible plastics laminates with PET/BOPPS/ Foil, etc., coextruded multilayer film (blown or cast) structures, aluminium foil, and/ or paper board combinations with these for aseptic food packaging applications has increased rapidly due to logistic advantages. In unit containers, the films used may be of paper coated with wax, PE, BOPP, PET and EVA blends or other combinations depending on the product characteristics and the shelf-life required.

Bag-In-Box System :

This is a new aseptic packaging system, specifically designed for high and low acid products such as fruit juices, fruit syrups and dairy products. As a major advance in aseptic packaging technology, this new system combines, for the first time, the entire producer, retailer, and consumer advantages of bag-in-box with high integrity aseptic filling and packaging. The system is easy to install, simple to use, eliminates the risk of product contamination during and after filling, and provides totally sealed, longer life packs. Its salient features are given below:

	Used for fruit juices, syrups, concentrates, dairy related products, etc.
	No risk of product contamination during or after filling
	No need for artificial environment - positive sterilization at the point of fill, no chemical sterilants used
	Totally sealed pack is not dependent on 'friction-fit' components
	Aseptic fill needs no product preservatives
	Filling system is easy to install and simple to use
	Minimal energy requirements
	Used for bag-in-box packs form 1 to 30 litres

Bag-in-Box System for Bulk Packaging

An important development of aseptic packaging technology is the bag-in-box system for bulk packaging of various food products. The system consists of a bag, which is made, of a packaging material having high strength and excellent barrier properties, which could be presterilized by suitable means.
The bag-in-box packages are generally of the capacity from 1 to 1000 litres. Bags are also available as liners for 200 litre capacity containers. Bags are mostly of laminates of substrate such as foil, nylon, PET, BOPP, LDPE / LLDPE, EVA, etc. The box in the system of bag-in-box is generally made of corrugated fibre-board of suitable construction with optimum strength and cushioning properties. The box provides not only physical protection for the bag, but also stacking strength and a means for transportation and handling. The 200 litres bags in contained in a box of steel or fibre-board drum and the 100 litres has an outer container of collapsible and reusable plywood shipping container. Often, a tap is provided for dispensing the contents.
The advantages of the bag-in-box system of aseptic packaging are

	It occupies less storage space, since the empty package is transported in a knocked down condition
	The transit weight of containers is reduced as both the empty and filled containers weigh less than metal, glass and rigid plastic containers
	Filled pallet loads are stable, because the square shape of the filled package makes standard stacking patterns possible - Packaging material cost is lower than other types of packages.

The products being packed and edible oils, fruit juice concentrates, non-carbonated beverages, alcoholic beverages, mineral water etc.

The Tetra Pack System :

In the Tetra Pack System, a sterile product is packed under sterile conditions, which remains sterile until it is opened.
To achieve this result, the system demands the fulfillment of the following conditions:

	Product sterilization - Packaging material sterilization
	Sterile surrounding while forming and filling the cartons The products mainly packed are milk, non-carbonated beverages, edible oils, etc.

THE PACKAGING MATERIAL :

The primary function of the packaging material is to protect the sterility of the product and be compatible with the product itself. The Tetra Pack system uses paper-plastic laminates for the purpose. Two concepts are in vogue providing extended shelf-life and log life to a product.
Apart from providing protection to the sterilized product, the paper and plastics play important roles in the package. Paper helps in shaping the pack and keeping the shapes, while giving mechanical strength to the pack. Paper is cheaper, lighter, easily storable and provides an excellent printing surface. The plastic layer on the printing side provides protection to the print, while the inner plastic layer imparts the heat sealabililty property. Both layers of plastic act as gas barriers.

Product Sterilization :

The product sterilization is carried out by the in-process or on-line sterilization, which is popularly known as the ultra high temperature (UHT) or high temperature short time (HIST) depending on the product treatment.

GAS EXCHANGE TECHNIQUES IN PACKAGING :

Gas exchange can be defined as the alteration of the proportional volumes of the gases, which comprise a normal atmosphere. For packaging this would be the air which might surround a food product within a package.
The gaseous composition of air by volume is:

	78.8% nitrogen (N2) which is a completely inert gas
	20.95% oxygen (O2) which assists microbial growth at ambient temperatures and causes deterioration of some products through oxidation
	0.93% argon which is also inert
	0.03% carbon dioxide (CO2) which although an inert gas has an inhibiting effect on microbial growth in the
	1°C to +2°C temperature range. (Remaining 0.01% is made up of insignificant quantities of neon, helium, krypton, and xenon).

Correct Gas Mixture : The inhibiting gas or mixture of gases might involve using nitrogen only or one of the following mixtures: nitrogen/oxygen; carbon dioxide/oxygen; carbon dioxide/nitrogen/oxygen; or nitrogen or carbon dioxide as single gases.

Form of Package :

A number of types of package are used which include lidded thermoformed packs made, filled and processed on the thermoform-fill seal (TFFS) machines, overwrapped trays, pillow packs produced on vertical form-fill-seal machines (VFFS) or horizontal form-fill-seal machines (HFFS), and various bulk packs.
Gas Flushing techniques are also used in bottling certain liquids.

Packaging Material :

Various plastics films can be used depending on the degree of gas retention required inside the package and the barrier properties needed to resist gas penetration from outside the package. Monopoly, laminate and coextruded material all have their particular applications.
The packaging material principally used in Western countries is a PVC/PE laminate. A coextruded material comprising PS/EVO/PE can also be used but it is less transparent than the laminated structure. Lidding material are usually laminates such as PVDE coated PET/PE. Pillow packs produced on HFFS or VFFS machines fitted with gas flushing equipments are providing to be effective modified atmosphere packs.
The demand for pre-packaged fresh foods free of preservatives is increasing. To enable the retailers to meet the demand of extended shelf-life, gas exchange techniques will have to be adopted on large scale.

Nomenclature :

Two forms of nomenclature have been used to describe gas exchange technologies: controlled atmosphere packaging (CAP) and modified atmosphere packaging (MAP). A distinction is now being made between these two terms.
Some of the Products being Packed using Gas Exchange

	Red meat portion packs
	Fresh fish
	Bakery Products
	Fresh pasta specialties
	Fresh salad
	French fries

VACUUM AND GAS PACKAGING :

Many products, particularly foodstuffs, are adversely affected by oxygen so that the attainment of the reasonable shelf-life is dependent on exclusion of oxygen from the package. One method of doing this is by vacuum packaging, whereby the air is removed from the package by vacuum pumps. The prevention of subsequent oxygen ingress obviously demands a packaging material with very high barrier properties and such barrier properties can only be achieved by the use of multi-layer webs.
Another method is inert gas packaging. The gases normally used are nitrogen (N2) and carbondioxide (CO2), N2 is completely inert and when used to replace air inside a package it prevents the oxidation of oxygen sensitive products. CO2 acts in a similar way but additionally it inhibits bacterial growth within packages when stored at low temperatures.
This property of CO2 has led to its use both alone a d in combination with other gases in the form of modified atmosphere packaging.
There are, then, two basic methods of gas packaging :

	Modified atmosphere packaging (MAP) which uses gas mixtures, usually containing CO2 to prevent bacterial growth, which would lead to putrefaction.
	Single gas flushing with N2 or CO2 to prevent oxidation of the product and subsequent deterioration.