Form-fill-seal packs

There are some more specialised systems for PET bottles, cans, other plastic bottles, form-fill-seal packs and returnable PET or glass bottles for still and carbonated drinks (generally high acid). These are material-dependent solutions and each arises from the limitations and properties of the materials and the way they are formed into containers. 

Form—fill—seal packs are also suitable for aseptic production. The pack is blown aseptically in a mould and filled through the soft neck. Once filling is complete the fill tube is retracted and the neck sealed with heat and pressure. 

An alternative form of non-carbonated beverage comes in form-fill-seal plastic containers, which are typically square or round section cups with foil or plastic laminate lidding. Such products are difficult to produce to a quality that will satisfactorily compete with the shelf fife of aseptic foil/laminate packs. Fonn-fill-seal containers leave their contents vulnerable to oxidative degradation and are especially at risk of mould spoilage. The packs can be produced in aseptic conditions but the products are typically chemically preserved. 

Various alternative configurations can be used, and in particular some manufacturers employ non-aseptic form-fill-seal operations which usually produce either in-line cup packs or cartons such as TetraPak or Combibloc packs. 

Many non-carbonated RTD products that are not pure fruit juices or nectars are packed in either pre-fonned or form-fill-seal plastic packages, although an... 

All the above processes can also be used in a form fill seal process with, for example, thermoforming and cold forming blister packs. Rommelag type bottle pack systems use an extrusion process where the container is formed by either blowing or vacuum (smaller sizes). Immediately after this, containers are filled, and the pack is sealed (welded) by using the residual heat in an extension to the main body of the container. 

Polyethylene, as LDPE, LLDPE or a mixture or blend involving combinations of LDPE, MDPE, HDPE, EVA, etc., finds a wide usage in bags, sacks, sachets, overwraps, shrink wraps, stretch wraps, etc. Most deep freeze packs, for example, use LDPE or an LDPE mixture which is produced from a reel on a form fill seal type machine. However, as many of these packs are up to 100% printed, even ink of 2-5 Pm could be considered as a separate layer which modifies some of the physical and chemical properties. As all polyolefins need a surface (oxidative) treatment to ensure a good print key, this or any other surface treatment process may further modify the film properties. 

Hot-fill pouches are used for both low- and high-acid applications. Heinz Company s form-fill seal Pouch Pack, which is claimed to give a shelf life of one year, has a web of 3-mil LLDPE, ethylene-acrylic acid copolymer, 35-gauge foil, ethylene-acrylic acid copolymer, and biaxially oriented nylon, from inside outward. The Pouch Pack system from Du Pont offers pouches of sizes 4 oz to 1.5 L to fill a range of high-and low-acid food applications at various temperatures, including fruit toppings at 80°C. 

In this, the air is replaced by passing a stream of gas. The gas flush technique is normally accomphshed on a form fill-seal machine. The replacement of air inside a pack-... 

There are a number of well-established systems for the aseptic packaging of liquids. Notable among these are those packs constructed, box form, in situ on the filling line from a cardboard, aluminium, plastic laminate sheet, such as TetraPak or Combi-box. In the TetraPak system, the packing material enters the filling machine from a feed roll the sheet contact surface is sterilised with warm hydrogen peroxide solution it is formed into a tube, and its lower end is heat-sealed across the width the tube is filled, sealed at the upper end, cut and then folded into a box shape. This produces a continuous output of filled cartons with premium utilisation of bulk storage capacity. 

Most fruit juices for retail sale are now in cartons, a high proportion of which will be aseptic packs. Cartons are formed, filled and sealed in a single operation, which will either be clean or aseptic depending on the product and shelf life sought. Typical packs include TetraPaks, Combibloc and Elopak. 

Inert gas sniffing of form, fill and seal packs... 

Canned and bottled citrus juices are examples of products that are packed aseptically, and these processes have been used in the industry for many years. One of the newer processes for aseptic packaging employs a paperboard package that is sterilized with hydrogen peroxide prior to the form, fill, and seal operation. This process, developed by Tetra Pak Ab of Lund, Sweden, is in use in many parts of the world, but it has not yet been approved by the U.S. Food and Drug Administration for domestic use. 

Paper is used extensively in laminations where it is bonded, usually by heat and/or adhesive, to other films, notably plastics and aluminium, e.g. LDPE/adhesive/aluminium/adhesive/calendered paper. This type of lamination can be used for form fill and seal work, e.g. sachet packs of deliquescent powders. 

The filling and packaging operations may take place on one piece of machinery or be split across several machines, namely form fill and seal—e.g. blister packs where the product is filled, closed and identified on one machine—whereas a bottle of liquid... 

The types of pack that are sealed straight away on the filling line include blister packs, strip packs, pillow packs, ampoule filling and Rommelag/ALP form fill and seal systems. 

Most plastic ampoules are from the blow-fill-seal types of containers. These containers are formed, filled and closed in one production lane and are therefore not available as an empty container for small scale filling. Some of these plastic containers are known as bottle-pack. These plastic containers are designed for sterile liquid pharmaceutical preparations, which can be opened by tearing, screwing or perforating. The bottle-pack-assortment contains a wide range of containers from ampoules to bottles (1-1,000 mL). 

It is possible either to rewind the coated substrate, and it will be used later by a customer who wants to pack some goods by form-fill and seal technique, or the coated substrate may be laminated immediately to another material, for instance to manufacture packaging laminates (refer to the chapter Packaging Adhesives in Volume 4). 

Lidding. Whatever the forming process, the end result, partway down the machine, is that of a pocket containing product that needs sealing. In both cases the lidding material is roll fed and sealed by heat and pressure to the filled formed pocket in the substrate. The printed sealing layer may need to be very accurately placed (e.g., calendar packs). 

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