Even by the lofty standards of mid-20th-century advancement, 1966 was a momentous year. The world’s first Automated Teller Machine (ATM) was unveiled in the US, as was The Brown Box, the first multiplayer, multiprogram video game system that has come to be known as “the grandfather of all modern video games”. The Soviets achieved the first controlled soft landing on the moon with Luna 9, while their Luna 10 became the first spacecraft to enter lunar orbit. And Tetra Pak introduced the Tetra Rex® packaging system.
This now-familiar gable-top package has become a modern icon over its near seven-decade existence, a permanent fixture on breakfast tables and in café refrigerators. Yet the package’s basic design and concept has a much longer history, predating even WWII. The first known patent for a milk carton was filed by one John Von Wormer in 1915, for a design that looks remarkably similar to today’s iterations; the term “gable-top” refers to the innovation of the spout being temporarily glued into a ridge and opened by a pinching-pulling motion.
Inspired by the recent appearance of refrigeration technology, and the need to find a cheaper, more efficient method of distributing fresh milk among the masses, these early versions were made of a waxy paperboard, and were noted for their economy of raw materials (no cap was required; nor was heavy, expensive glass). However, perhaps because of their somewhat rudimentary, fragile nature – without additional protective layers or barriers, they were prone to leaking – and the ubiquity and enduring popularity of glass bottles, it was several decades before gable-top packaging came to be seen as a true alternative for milk, dairy, and a number of other chilled beverages.
The shift happened at different times in different geographical markets, even though in some places, such as Japan, glass bottles still endure, particularly for home delivery. In America, the 1950s saw a surge in carton packaging popularity, driven mainly by their convenience, durability and cost-effectiveness. So, too, did Sweden; 1953 saw the debut of a half-litre carton package for milk, which was adopted for commercial use by both Mjölkcentralen and Lundamejeriet (Tetra Pak followed in 1966). Such a switch revolutionised the industry.
After all, the benefits were clear. For producers, they simplified production – packages were delivered as flat blanks to be formed, filled, and sealed by machines, reducing production time and costs, while the stackable design optimised storage space and efficient transportation. Consumers now had convenience, portability, and ease of use; product hygiene and food safety were markedly improved, too.
Constant innovation and refinement were also key to mass market adoption. The addition of plastic film made these packages impermeable to liquids and heat-sealable; later, at the end of the 1960s, a layer of aluminium foil ensured even better protection and extended the shelf life of packaged beverages.
Hygiene was a focus during the 1980s. The TR/7 HH was introduced in 1982, a filling machine whose improved performance increased the shelf life of products from seven to approximately fourteen days (the HH stood for High Hygiene). In 1985, the TR/8 improved the hygiene level even further, could fill 6,000 to 6,500 packs per hour, and had a smaller footprint – 423 of these were sold globally between 1981 and 2003 (67 of them remain in use today).
One of the most significant innovations came in 1992, with a solution to the longstanding issue of re-sealability and the need to store packages upright after opening – the introduction of closable flip caps. These closures had a tamper evidence and used hotmelt when glued onto the package; they were also introduced in five colours – green, red, white, dark blue and orange.
Since then, Tetra Rex – and the innovations behind both the package itself and filling machine technology – has continued to improve and evolve, strengthening its status as an iconic pioneer. In 1993 and 1994, Extended Shelf Life (ESL) technology in the form of the UV and peroxide systems were introduced, while in 1997, the first High Acid Ambient Distribution (HAAD) machine for ambient distribution, the TR/16 HAAD, was introduced. 2000 saw a new shape, Tetra Rex Plus – it had a skewed gable top to accommodate a larger closure – make its debut, while developments in materials, openings, filling speed, and hygiene continued apace.
And yet another world first was achieved in 2015, with the launch of the world’s first fully renewable carton package, the Tetra Rex Plant-based. Made solely from a combination of paperboard and polymers derived from sugarcane, the package set a new standard for sustainability – something it continues to do thanks to the global availability of Tetra Rex Plant-based with Tetra Pak® Craft.
So, what’s next for Tetra Rex? The challenge remains balancing functionality and material usage – this is a constant trade-off. Without sacrificing performance or quality, a package must now be suitable for an ever-increasing variety of products, such as yoghurt with particles or super skimmed milk, all of which require different settings and parameters for filling, and may even need different materials for protection.
This variety of products reflects shifting consumer trends, consumption habits, demand, and product evolution. This is why the term “future-proof” can mean different things, and encompass different aspects. Yet Tetra Rex remains adaptable, and stands ready to face the packaging challenges of the future.
With QuickChange™, producers can easily run, and switch between, different volumes, meeting demand for better-value products or smaller volumes. Another aspect is producers’ desire to pack yoghurt and plant-based alternatives, which are still being developed – these new products require different filling settings or different volumes (as an example, value-added products such as protein-enriched milk would usually sell in smaller packages – 500-750ml – than standard milk, which typically comes in 1000ml).
Truly a pioneer since its introduction 68 years ago, Tetra Rex has proved its worth to producers and consumers alike – flexible, dependable, safe, and high quality. These attributes remain core values, and guide the package’s development as it continues to lead the way as a modern, convenient, chilled packaging solution. That’s why this design remains the King for a whole range of chilled products – and a whole generation of consumers who recognise and trust a truly iconic package.
