The requirements on closure solutions protecting products in the food and beverages industry in particular are not only extremely varied – they are often very specific, whereby selection of the suitable compounds is influenced by
beverage containers – glass bottles or PET, disposable or reusable packaging
stress – changing temperatures, transport and storage, rate of circulation, head pressure, clear traces of usage, material abrasion
closures – crown corks, plastic or vacuum closures
filling – cold, cold-aseptic, hot, pasteurization, sterilization
beverages – fruit juices, fizzy soft drinks, fizzy or still alcoholic beverages, mineral water, milk and dairy products, tea, sensitive contents etc.
which are developed and optimized in close cooperation with the manufacturers of closures and brand items.
In the case of beverages in particular, one key factor is represented by retention of the original organoleptic properties, neutrality in terms of taste (especially for mineral water), aroma and protection from foreign odors incurred during transport and storage.
Where highly-carbonated alcoholic beverages are involved, sealings of the maximum technical level are required. As is a barrier function. Barrier compounds display an increased barrier effect when it comes to penetration by a wide variety of gaseous substances, including oxygen, 2,4,6 Trichloranisol (TCA)* and other volatile organic compounds which can lead to sensory deterioration in the case of beer, juices and other contents. Carbon dioxide emissions from the bottle are significantly reduced. In this environment – as in bottle ageing for champagne and sparkling wine – Peak-Free® technology is particularly popular for applications involving sensitive contents. Scavenger compounds also have an oxygenating effect as they absorb the oxygen present in the sealed bottle and prevent penetration by oxygen from the outside. In the form of scavenger compounds on the one hand and barrier compounds on the other, two different technologies are available for protecting sensitive contents from influences affecting taste as well as extending the shelf life.
As already described for the materials used in medical technical applications, it can also be of importance in the food sector that the compounds can be sterilized, e.g. for contents such as dairy products.
Creative freedom – especially for promotion campaigns, marketing purposes, product launches, marking for traceability or brand protection – is provided by laser-arkable seals. This is where the most demanding requirements are often made on marking closure seals. Solutions are offered by the in-shell and out-shell process, whereby not only alphanumerical codings are possible but even complex graphics and logos can be reproduced in detail. PVC-free Polyliner® products offered by Actega DS – with FDA and EU approval – are free of heavy metals while optimum results are achieved using an Nd:YAG laser.
* 2,4,6 Trichloranisol (TCA) is a chlorinated, aromatic hydrocarbon with an intensive moldy-musty odor. This phenol derivative is the main reason for a corky taste – the most significant olfactory-gustatory wine flaw.