Innovating to solve the impossible: world-first recyclable retort flexible packaging

Updated July 2023

Noemi Bertolino, Vice President R&D, Amcor Flexibles AFEMEA and Gerald Rebitzer, Director Sustainability Amcor Flexibles discuss the challenge presented by retort pouches and look back on how Amcor’s teams brought the first recyclable version to market.

Q. First of all, what is retort packaging?

Noemi Bertolino: In retort processing, typically the food is cooked inside the pouch at temperatures up to 130 degrees Celsius. This sterilizes the product and its packaging, which is sealed against oxygen and bacteria, so the food will not spoil and remain safe to eat for about one to two years.

Q. Knowing it was one of the most difficult technical challenges in flexible packaging, why try to develop a recyclable retort pouch?

Gerald Rebitzer: There were several reasons. First there’s Amcor’s pledge to develop all our packaging to be recyclable or reusable by 2025. More recyclable packaging is something that our customers (the brand owners), retailers and consumers very clearly want. And perhaps most importantly, we have a product development team with immense talent and a passion for applying their talents to make packaging more sustainable.

Despite an unprecedented global pandemic, sustainable packaging continues to be a hot topic. Our recent research shows that global warming and plastic pollution are high on consumers’ agendas. They expect their favorite brands to provide more responsible packaging and brands are keen to show they are listening by offering recyclable, more sustainable options.

Until now there wasn’t a retort pouch that combined recyclability with the performance required to withstand heat-sterilisation and provide a long shelf life. But our teams like finding solutions. Particularly if we’ve been told it’s impossible.

If you want to learn more about our research into what shoppers expect from brands like yours download the full report.

Q. What challenges did Amcor face developing the recyclable retort pouch?

Noemi Bertolino: Restorable and recyclable? Everyone thought this was impossible. But we believed we had the capabilities and the determination to achieve such a breakthrough.

Flexible retort packaging, that protects ready-meals or wet pet-food for example, keeps the food inside fresh for a long time by using high performing materials; usually a combination of different plastics that often includes aluminum. For years, the outer layer of a retort pouch has been made with PET, because it has high heat resistance. The problem with this however, is that there is no recycling stream available for PET-based bags and pouches (the so called “soft” plastics), unlike PET bottles, which are recyclable.

Additionally, standard retort pouches use a layer of aluminium to keep out oxygen and bacteria. While aluminum on its own is recyclable, when sandwiched between layers of different plastics, it can create problems in the recycling stream.

Neither of these two materials is compatible with existing recycling streams for plastic pouches and bags. The PET and aluminum layers needed to be replaced with a recyclable alternative.

__Q. What are the challenges of PET in flexible or "soft" packaging? __

GR: PET has all the features of an ideal packaging material: it runs well on production machines, works well as a base-film for barrier coatings and is heat resistant. Additionally, our customers can run it easily on their filling lines. It’s high performing in nearly all areas – but its Achilles’ heel is that it is not recyclable.

NB: Unlike PET bottles and containers, there is no plastic recycling stream for flexible packaging that accepts PET. The polyester used in bags and pouches is often printed and combined with other materials in the finished pack. This is different than PET bottles which represent a pure, high-quality form of PET. The bottles are transparent and many of them don’t contain any dyes.

__Watch our video to learn more about AmLite HeatFlex® Recycle-Ready. __

__Q. What is the new recyclable retort pouch made with? __

NB: We knew we needed to move to a fully polyolefin structure as aluminium was not an option and paper cannot withstand the steam retort process. Polyolefin's include PP and PE, and bags and pouches made with these materials are recycled today in many countries.

The difficulty in moving to polyolefin's for retort is that only PP can have a melting point higher than 130 degrees Celsius, which is easily the temperature reached for retort processing. Therefore we had only one option: we had to develop a solution based on PP.

We had successfully launched our high-barrier polyolefin film for non-retort applications in 2018, so now the challenge was to develop a suitable overall PP solution for retort applications.

It took a lot of problem solving and more than two years of collaboration with our customer to get there, but in October 2020 the first recyclable PP retort pouches were launched in the market for wet cat food.

Q. Did you experience any set-backs during the development process?

NB: When you face such a big technical challenge, not everything goes as planned. You need to find innovative solutions and accept that there will be many situations when you fail.

Resilience helped us move forward. When things did not go as expected, the team did not give up, and instead built on previous learnings, reached out to our global R&D community, and involved other experts.

For AmLite HeatFlex® Recycle-Ready to come to life, we needed to conduct a lot testing and combine the expertise of different Amcor production sites. Everyone was truly engaged. For example, when samples would arrive at a plant for trials, everything was planned down to the minute. There was a high sense of purpose and urgency for all the teams involved – we knew this product would make a difference from a sustainable packaging perspective and that gave us the energy and creativity we needed to progress.

We were proud to see the first wet cat food pouches appear in stores in October 2020.

Q. What does this packaging innovation mean for pet food and beyond?

GR: This revolutionary pouch opens a very important door on recyclability for retort. Flexible retort packaging already helps brands minimize carbon footprint thanks to its light weight, resource efficiency and ease of transport. By adding recyclability to its properties, brand owners and retailers can reduce their packaging's carbon footprint by up to 60%.*

AmLite HeatFlex® Recycle-Ready is certified as recyclable by cyclos-HTP Institute, an independent testing lab, and meets the packaging guidelines for a circular economy recently published by the CEFLEX Consortium. It can be easily recycled within plastic collection streams already existing in several European countries, including Germany, Austria, Italy, Norway and The Netherlands.

Today, these pouches can be recycled into many different products, including industrial fibres, food containers, dish-ware or compost bins. As chemical recycling scales up in the future, the pouches could be recycled back into virgin-grade materials.

As a next step, we continue to work on our portfolio to address other retort applications such as gusseted pouches and lidding materials. We are already working in partnership with Mars Food, to bring the first food-safe, recycle-ready microwavable rice pouch to market in 2021.

Find out more about AmLite HeatFlex® Recycle-Ready.

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*Carbon footprint comparison based on Amcor’s ASSET lifecycle assessment system, certified by the Carbon Trust. Comparison based on standard retort packaging using a PET/Aluminum foil/PP pouch, versus the new AmLite HeatFlex® Recycle-Ready OPP/AmLite SiOx barrier/PP pouch. Maximum carbon footprint reduction of 60% assumes 100% recycling of the AmLite HeatFlex® Recycle-Ready pouch.