Aseptic fillers have to meet demand for extended shelf life and pack convenience – but the bottom line is product safety. Pauline Covell reports on the latest developments in aseptic technology

There is really only one issue when it comes to aseptic filling. Food, drinks and pharmaceuticals manufacturers need to be sure they are investing in 100% certainty.

That’s understandable – we are talking about people’s health and safety here. Users have to be positive that when they code the extended shelf life on an aseptically filled product it is absolutely correct.

As Jack Lloyd, sales executive at Engelmann & Buckham – UK agent for both SIG Hamba and Hassia – puts it: “When people invest in this equipment they are looking for guaranteed sterility. The bottle, transport and filling machine all have to be sterile.”

Latest from Hassia is the aseptic version of its stick pack form, fill and seal machine. Designated the SAS 20/30 and launched during Interpack, it is believed to be the only one of its kind able to aseptically handle UHT milk and long shelf life products such as desserts.

“Where we believe we will have a lot of success is in the replacement of the small milk jiggers for portion packs of UHT milk,” reveals Jack Lloyd. “All the dairies are showing a lot of interest. Some people have queried if the pack is strong enough and whether it will prove difficult to handle but actually the stick pack is quite solid. It is easy to keep the milk in one end of the pack and hold and tear the pack without the milk leaking.

“The jigger, on the other hand, is notoriously difficult. Who hasn’t had the embarrassing experience of squirting milk over the person in the next seat on the plane?

“And the seals are very tough too. With the jiggers one leaker will destroy the whole box. More stick packs can be contained in one box. So there will be space reductions.”

The company is currently researching the cost savings over the jigger. “At about £1M the machine is around the same price as the thermoform, fill and seal equipment for the jiggers, and barrier materials have to be used in both cases,” he admits.

The SAS 20/30 is designed for a performance of 8 stick packs/cycle, producing up to 24 000 units/hr.

“We can’t play around with the width but we can alter the pack length so different volumes can be achieved,” explains Jack Lloyd. Film coming off the reel is sprayed with hydrogen peroxide and dried with sterile air. Hot sterile air also surrounds the filler.

It is understood that the company supplied a stick pack machine to ConAgra Foods, US for chocolate mousse for the lunch box and the ‘on the go’ food market. ConAgra developed the new refrigerated, ready-to-eat snacks through a licensing agreement with Hershey Foods Corp.

The tubes are made by a proprietary source from what ConAgra Foods describes as a multilayer metallized filmstock, flexo-printed in at least five colours, reports Packaging Digest, US. The packages are produced at the company’s pudding plant in Menomonie, WI.

“It’s a totally new sweet snack and dessert alternative,” notes ConAgra Foods brand manager Charlene Lee. “Hershey’s portable pudding puts an innovative spin on a fantastic, well-known brand.” It can also be frozen.

Interest in the stick pack format continues apace, confirms Derek Moore, managing director of Stickpack Europe. “Our machine is easily changed to full aseptic with very little modification. We can use UV sterilisation and hydrogen peroxide spray to achieve full aseptic use with or without an environmental air handling system,” he explains.

“The main point is that no redesign of the machine is needed and it is reasonably priced. And, as it is continuous motion with servo driven pumps, we are looking at speeds of 800-1000/min to 60000/hr.”

Pampryl has become the first French producer to adopt aseptically filled multi-layer PET for its ambient-stored 100% fruit juices.

Explains Amcor PET Packaging Europe/Asia R&D manager at Brecht, Frank Haesendonckx: “We have developed preforms in multilayer, Bind-Ox, which is basically an active barrier preform for oxygen. That is to say the barrier layer prevents any oxygen from entering through the bottle wall, as it will be scavenged before reaching the inner wall.”

To cover the juice product range, the company developed a 26g preform for the 500ml size, a 39g preform for 750ml and 1-litre and a 52g preform for 1.5-litre square Pampryl bottles.

“The solution has allowed the Pampryl to replace the current Barex pack with a multilayer PET preform, resulting in an even better performance and shelf life of the product.” They are said to ensure a 12-month shelf life for juices, a further development of their existing nine-month capabilities.

“Preforms are delivered to the Pampryl plant at Nuit St Georges in France where they are stretch blow-moulded on a Sidel SBO10. Here the preform is re-heated by IR lamps in an oven, then transferred into the blow mould and stretched mechanically by a so-called stretch rod.

“High pressure air is fed into the preform through a blow nozzle, blowing out the balloon into a bottle by stretching the material vertically and radially against the bottle mould wall,” says Frank Haesendonckx.

The Sidel unit, which replaces seven extrusion blow moulders, runs at 1400 bottles/hr/mould and, after blowing, the containers are transferred into silos from where they are distributed for filling when required.

From the silo bottles travel through a rinser onto a Serac aseptic filler comprising cleaning/rinsing, filling and capping in an over-pressurised sterile environment. Capping is performed on a Zalkin unit using Bericap 38mm monopiece caps.

“On 1-litre production the line is rated at 185 bottles/min,” reports Mr Haesendonckx. Labelling and case packing complete the line.

Hamba’s aseptic bottle filling and closing machines, which are said to “guarantee re-infection free filling in a sterile environment”, operate on a similar principle to the German company’s pot fillers.

Typical applications are long shelf life UHT milks and yoghurt drinks as well as fruit juices, teas and sports drinks. End users include a leading Brazilian food and drink producer Parmalat, Campina of Belgium and Müller’s German operation.

Enclosed, the equipment operates in line rather than on the rotary principle. This means that the footprint can be relatively small, at 11x2m, says Jack Lloyd. “The intermittent BK 220 000 fills up to 18 000 0.5-litre bottles /hr on a 12-up format.

“Although it cannot fill handled containers, it is flexible on size. What is important is that the bottles are held by the neck so that as long as the neck profile is the same you can fill from 200ml to 2-litre containers on the same line.”

Sterilisation of the container is completed by exposure to atomised hydrogen peroxide and heated sterile air. Pre-cut heat seal membranes or caps are also sterilised with hydrogen peroxide before being sealed onto the bottle.

Alternatively, a system for sterilised screw caps is available. The programmable plc is said to guarantee the automatic sequence from production through to cleaning and sterilisation.

Aseptic filling has proved to be an important facet in the partnership between D S Smith Group company Rapak, a leading supplier of bag-in-box systems, and Dayla the UK’s largest independent bag-in-box filler.

The specialist in filling for the foods service industry cites the control of hygiene issues as vital.

One very good example of the pace of change is the patented Intasept filling system which Rapak supplies to Dayla. Intasept produces a steam sterilised environment around a special double-membraned filling gland. The small sterilisation area enables all the variables to be controlled with total precision, giving 100% aseptic conditions, claims the company.

After filling, the system seals the bottom membrane to complete a tamper evident bag. A benefit is claimed to be the way it prolongs drink shelf life, opening up new marketing and distribution opportunities.

It can transfer from 200-litre drums or from up to 1000-litre IBCs. Suitable for high or low acid products, it eliminates the need for re-pasteurisation.

Dayla’s managing director, Ian Jenkins, believes such technology is helping to drive up standards in the food services industry. “The benefits of bag-in-box as a packaging format has come into its own. Bag-in-box has proved itself to be ideal for products such as post mix syrups, juices, and concentrates. But we’re also providing ingredients, sauces and fruit purees in bag-in-box formats. It is becoming cost effective for retail opportunities in pack sizes greater than 3 litres.

“The Van Meurs bag-in-box machine offers maximum flexibility in terms of its ability to fill bags from 5 litres to 1200 litres,” says Bob Cragg of Terlet UK. “And it can handle all current bag and closure types so the user is able to shop around for the best value packaging materials.”

The company is part of the Dutch MPE Group which includes specialist in food and dairy processing lines Terlet. “This means that the complete line, including vessels, pipework, controls, and the aseptic filling machine can be supplied from one source,” he adds.

Conveyor height is adjustable to accommodate different bag sizes and the conveyor can be easily removed when filling large containers. Change from one type of closure to another can be achieved in about 20 minutes, including re-sterilisation of the filling head, claims the company. Semi-automatic or fully automatic options are available and all Van Meurs filling machines are delivered with clean-in-place provisions as standard.

Bob Cragg adds: “The filling system is particularly suitable for heat sensitive products such as liquid egg. Nitrogen is used to gas flush the bag instead of steam. Van Meurs claims that the majority of liquid egg processors in the Benelux countries and Germany use its aseptic bag-in-box filling machines.”