More sustainable beverage packaging

2023-01-19

The variety of beverage containers is very wide: it covers PET or glass bottles, aluminum cans, cardboard boxes or even paper bottles, whether disposable or reusable. But which one is particularly sustainable? In recent years, ecological aspects have been gaining importance in this area. And not only with regard to packaging: the filling and packaging processes are also decisive.

Some drinks are still presented in their classic packaging. Beer and wine are usually bought in glass bottles, milk in cardboard containers and soft drinks in PET bottles. However, in recent years aspects related to sustainability have also gained importance in the beverage sector, and consumers have become more critical. In particular, plastic has fallen into disrepute, often unfairly. It should not be forgotten that the ecological balance of a package depends on many factors. Therefore, experts are reluctant to make general recommendations.

The ClipAside stoppers attached to the beverage bottle already comply with the EU Directive 2019/904 to improve recycling. © Bericap

As a summary, let’s remember that glass bottles are tasteless, but also fragile and heavy; however, they can be reused in many more cycles than any other container. PET bottles can also be refilled several times before being recycled. They are unbreakable and much lighter than glass bottles. Despite this, plastic has long had a very bad image among customers, although the recycling rate of PET bottles for drinks in Germany is very high, over 94%. Drinks in aluminum cans are still popular. However, the extraction of the raw material and the production of the cans from the raw aluminum consume an enormous amount of energy; hence the relevance of its collection fee, since the cans can be recycled as many times as desired. Cardboard containers for drinks are always disposable, although most of them are made from renewable raw materials. The improved processes now make it possible to separate the cardboard, aluminum and plastic components. For this reason, the German Federal Environment Agency classifies them as “disposable packaging with ecological advantages”.

At the doors of the paper bottle?

At the end of 2016, the Carlsberg group presented for the first time with the Green Fiber Bottle the prototype of a paper bottle. In the summer of 2020, the beverage consortium Diageo announced the first paper-made liquor bottle for Johnnie Walker Scotch whiskey, but it has not yet been widely released on the market. At the beginning of 2021, Coca-Cola offered a vegetable drink in a paper bottle to 2,000 consumers in Hungary for the first time in Europe. For now, this initiative has also remained in the testing phase.

Since the sustainable fiber bottles were developed, we have been continuously working to optimize them with the aim of achieving a completely biological paper bottle. At present, the “classic” paper bottle continues to be made from paper and a thin layer of PE; both materials can be easily separated in the process of paper waste treatment for recycling. However, one disadvantage of polyethylene is that it does not work well with carbonated drinks, for which a slightly thicker PET coating is usually used.

This year, the Carlsberg brewery has taken a step forward: the bottles used for a large-scale consumer test are coated with PEF (polyethylene furanoate), a polymer of biological origin with properties similar to PET. It offers a very effective barrier between the beer and the outer layer of fibers, protects the flavor and seems to retain the carbon dioxide of the beer better than conventional PET. In addition, the biopolymer is compatible with PET recycling systems and even degrades in nature. The current prototypes are already an improved version that include the PEF coating and a new base to improve the stability of the bottle. The next generation of bottles will also have a stopper and a fiber closure.

With the Mosca Saturn S6 wrapping machine, even fragile bottles can be optimally secured for transport to the supermarket. © Mosca

Lightweight and reusable glass bottle

Glass is a very popular packaging material among beverages. Its only significant drawback is the high weight, since PET bottles can even be up to 90% lighter than the reusable glass variant. However, glass packaging manufacturers are also working on lightweight versions, for example, lightweight glass with thermal tempering. The reusable bottles produced in this way are not only up to 30% lighter than the standard variant, but also more resistant to abrasion, which can make them a real alternative both from the economic and ecological point of view. However, heat treatment, which increases the final stability of the glass, imposes limitations on the design of the products. In the process, one of the great challenges is the variation of the wall thickness.

Well protected during transport

In order for bottles, cans and beverage boxes to arrive at the point of sale in perfect condition, they must be well protected during transportation. Thin sheets usually ensure a stable bond on the pallet. Machinery manufacturers, such as Mosca, interpack exhibitor, offer pallet strappers and balers for this purpose. Depending on the type of container, the fastening on the pallet must meet very different requirements. It should be avoided that the beverage cans are deformed and the glass bottles are broken. For the transport of light and empty beverage cans, for example, not only a side or top closure is required, but also a slight pressure must be exerted so that they are well secured during the journey to the beverage filling machines. The new Fly pallet strapping machine generates the necessary pressure on the empty cans by means of a vertical strapping. The plant uses sustainable PET strapping that is manufactured from recycled materials and packs/makes up to 61 pallets per hour for transportation, in a process that consumes few resources. As only a thin plastic strapping is used to protect even the heaviest pallets, material consumption and carbon footprint remain minimal.

Alternative to plastic shrink film

In Moderna balers, the film reel rotates horizontally around the pallet while the goods (i.e. full cans or fragile bottles) are kept static. An elastic wrapping film is often used that can stretch up to 300%. In this aspect, manufacturers also continue to work to find more sustainable solutions with renewable materials. For example, a pallet container made of elastic and puncture-resistant paper can make a completely recyclable packaging solution viable. A 100% recyclable paper solution for wrapping PET bottles has also recently been launched. It is a tape made entirely of kraft paper with which the bottles are wrapped, which offers great tensile strength and can also withstand enough weight to stabilize the bottles during transport. The second component of this solution is a corrugated cardboard clamp that holds the bottles by the neck. The bottles can be easily separated from the packaging.

Hygiene as an absolute priority

The can continues to be a popular beverage format. While previously it used to be canned mainly beers and carbonated soft drinks, for some time the trend has been covering more and more sensitive products, such as cold tea, vegetable drinks, juices, smoothies or flavored water. As a result of this evolution, the hygienic requirements that beverage filling machines must meet are increasing. Faced with this situation, the system supplier KHS, together with the Swiss machine manufacturer Ferrum, has developed the SmartCan filler-capper block and presents for the first time an optimal combination of its machines with an improved hygiene concept. The hygienic space of the filling section in the block consists, on the one hand, of raised enveloping plates and, on the other hand, of a housing with a clearly lower space for the product around the filling carousel: following the so-called “donut” principle, the housing surrounds it in the form of a ring, thus reducing the volume of the hygienic area by around 40% and guaranteeing an optimal and channeled flow of sterile air around the sensitive area.

Filling technology

Hygiene is also important in the new aseptic filling system that Sidel has developed for the growing market for sensitive beverages in PET bottles. The integrated blow, fill and seal solution is an evolution of the Aseptic Combi Predis technology and has been designed to help bottlers cope with the growing market demand for long-shelf-stable beverages such as juices, nectars, soft drinks, isotonic drinks and tea, as well as liquid dairy products. Sidel estimates that the demand for these products will reach 192,000 million units in 2024, 44% more than in 2011. According to the report, sensitive products account for 55% of the soft drinks market and the forecast growth of this share (annual growth rate of 2.3% between 2019 and 2025) is higher in PET bottles than in other materials.

Demand for flexibility

When packaging their products, bottlers are currently facing various economic and ecological challenges. On the one hand, they feel the increasing pressure of deadlines and costs; on the other, the beverage industry is currently in the crosshairs of legislation, in particular with regard to recycling rates and carbon emissions. In this context, KHS, interpack’s exhibitor, offers its customers a wide range of adaptable block solutions, especially for PET bottle packaging, including a new modular, configurable and expandable platform. These machines, which were installed for glass fillers in 2020, now also meet customers’ demands for customization and future-proofing for plastic bottles. “We cannot predict what the industry trends will be five years from now,” says Manfred Härtel, product manager Filling at KHS. “That is why we have designed the new platform with a modular design, so that it can be retrofitted for other beverages or PET containers at any time, depending on the needs of the market.” This makes it possible to acquire individual components later and integrate them into existing solutions without excessive effort. In addition, numerous design improvements make it possible to save energy. The new filler supports filling temperatures up to 24 degrees Celsius, which reduces operating costs and investment in energy-intensive cooling technology. In addition, condensation is not generated at these temperatures, thus avoiding the need for drying, with the high energy consumption that entails, before packaging in film or cardboard.

Caps attached to the bottle will soon be mandatory

Caps and valves are often a problem from the point of view of waste and recycling of plastic bottles. Therefore, the EU has legislated the use of closures that remain attached to the bottle from 2024. Many manufacturers have reacted to this requirement and have developed the so-called ‘tethered caps’, stoppers attached to the bottle. Beverage producers, including Coca-Cola, are implementing the EU directive ahead of schedule: the group already launched its bottle-attached stopper in 2021 and is expanding it to more and more non-returnable PET bottles. Consumers will not notice big changes: the opening mechanism remains the same, and the stopper, attached by a safety ring, can move freely on the neck of the bottle or be fixed in one position. The beverage group plans to progressively reconvert all plants in Germany until January 2024. It started with the Dorsten filling plant, located in North Rhine-Westphalia, at the end of 2021.

Manufacturers start from the assumption that, in order for consumers to accept the new caps, their handling has to be practical. In consumer studies, the tethered cap from interpack exhibitor Bericap got a good score for its intuitive operation, the possibility of opening it up to 180 degrees and the hygienic advantages. This indicates that suppliers who switch to this type of plugs on time will be able to increase the brand appeal of their products.

Smart closures

Consumer friendliness indicators are also useful in the beverage segment. Together with the start-up Mimica, United Caps has launched an ingenious closure solution with a fit-for-consumption indicator. The surface of the touch cap changes from smooth to uneven when a product can no longer be consumed. This is done by a gel integrated into a special label, capable of changing its structure. The recyclable closure is formed by the base of the lid and a stopper. It is applied after the filling process with a special machine that, like other modules, for example, for labeling or film wrapping, can be easily integrated into production. The consumer activates the effect when he opens the stopper by turning it for the first time. A pilot project on an orange juice brand is already underway in the UK.

The sustainable and innovative solutions available in the beverage industry will be showcased at interpack. From 4 to 10 May 2023, exhibitors at this world’s leading processing and packaging trade fair in Düsseldorf will present their latest developments along the entire value chain: from machines and equipment to various types of packaging, materials and recycling. It should be noted that in Hall 13, filling and packaging solutions for the beverage industry will have a special role.