SIG Targets 85% Paper In Aseptic Cartons: Aluminium-Free Still Has Enormous Room To Scale

I will say this plainly. The aluminium-free aseptic carton is a supply question rather than a technology question. SIG now says it is working towards 85% paper content in the pack. It has sold more than 5 billion packs with no aluminium layer since 2010. Zenith's Global Aseptic Packaging Market Report 2026 counts 344 billion aseptic packs filled in 2025 alone.

What SIG said this week

SIG set out its material plans in an interview published on 30 September. Gavin Steiner, the group's chief technology officer, said the 85% paper objective had been met. The next target is at least 90% paper content by 2030. That later figure counts the closure. The 85% does not.

Steiner also pointed at the rules. He said regulation is shaping how the trade behaves and levelling the ground for everyone. Demand is strongest in dairy, plant drinks, protein drinks, sauces, desserts and nutrition packs. Pouch and bag-in-box filling are the formats gaining ground.

What comes out of the carton

A standard aseptic carton holds three main materials. Paper carries the structure and polymer keeps the liquid in. A thin aluminium foil blocks oxygen and light. SIG cut that to two main materials in its full barrier pack. Polymer layers now do the oxygen work. Light is handled by fibre direction and by colours that soak it up.

The carbon sums are what make this worth doing. SIG says aluminium is about 5% of a carton by weight. Aluminium carries roughly 25% of the carbon footprint of a full barrier pack. Taking it out cuts that footprint by up to 61% when forest-based polymers go in too.

The number that puts it in scale

Zenith's report puts world aseptic volume at 148.4 billion litres in 2025. Cartons carry 66.5% of that. The more than 5 billion alu-free packs sold since 2010 are roughly 1.5% of one year's world packs. That is my own sum off the two published figures.

The split by product shows where the volume sits. Cartons carry 91.8% of the world's UHT white milk, on Zenith's figures. That is 52.7 billion litres of milk packed in 2025. Juice and plant drinks need the tougher barrier. That version only reached multi-serve packs in 2025.

Why the filling line is the easy part

The material runs on filling machines that are already installed. SIG says the swap needs minor changes and little money. Small packs run at up to 24,000 an hour. Multi-serve packs run at up to 15,000 an hour. No new line is needed to make the switch.

That is the part most coverage misses. A format change that needs a new filler moves at the speed of machine spending. A material change that runs on the old filler moves at the speed of board supply. Those are very different clocks.

The last five points sit in the cap

Getting from 85% to 90% means solving the closure. SIG has worked with Pulpac since 2025 on a dry moulded fibre cap and base. The closure is the one part of the pack nobody has made from paper at scale. It is also the part a filling machine applies last.

Tetra Pak is moving the same way. It put EUR 60 million into a pilot plant at Lund in Sweden for paper-based barriers. Its own 1 litre paper barrier carton reached shelves with Sterilgarda in Italy. Two of the big carton houses now point at the same structure.

What this means for the market

Most packaging plans treat this as a brand choice. The sharper read is a material supply question. An entrant should ask who can supply alu-free board into its market, and at what volume. The category mix sets the timetable. A market whose aseptic cartons are mostly UHT milk converts earlier than one built on juice.

One supplier's material change rarely moves a world market on its own. What matters is whether the same switch shows up across countries and categories. Our Global Aseptic Packaging Market Report 2026 sizes carton volume across 39 markets by category and pack size. That is the base you need to see how far a material change can travel.