NICOLA: Most food products are susceptible to moisture, light and oxygen, but some are more vulnerable than others. Within the snacking category, nuts are one of the most sensitive products, so they typically need a different packaging material than crisps or biscuits. The high fat content in nuts is one of the biggest factors, isn’t it?

KURT: Yes, exactly. Nuts have a high fat content, which can go rancid, so many types will lose quality and taste if exposed to oxygen. Dried fruits, meanwhile, will change their moisture content and change texture unless protected by a water vapour barrier. High-barrier packaging tailored to each product can help deliver consistent taste and freshness.

In the case of dried fruit and nuts, this is sometimes complicated by the fact that although these two products have very different packaging needs, they’re often combined in a single pack.

NICOLA: From your technical perspective, how should brands approach barrier selection for nuts and dried fruits?

KURT: Start with the type of product you’re packaging and how vulnerable it is to damage from light, air or water. For example, coated and roasted nuts contain a lot of fat, are heat-treated in the process and can become stale quickly when exposed to oxygen. Therefore, roasted nuts require a higher barrier than fresh nuts. Also think about the rate of sales you anticipate and the shelf life required. A high turn-over rate will allow a slightly lower barrier.

NICOLA: I’m often asked about the pros and cons of transparent packaging versus metallised packaging. One factor is the brand promise you want to deliver to your target market and whether it will be better communicated with metallisation or transparency. Is the product premium, mainstream or discount, for example?

In much of Europe and North America, consumers associate healthy, premium snacks with transparent packaging that allows them to see the product inside. In these markets, transparency gives brands the potential to apply a significant premium. However, as an exception, in Turkey, most consumers associate high quality nuts with metallised packaging, so it can vary by market. Do you have any other thoughts?

KURT: Yes, historically, a primary decision factor in choosing transparent high barrier versus metallised was cost, but this is no longer the case. The AmLite range of metal-free, high barrier laminates offers a selection of barriers to compete with aluminium-laminates and even PET-MET.

Sustainability is also a factor. AmLite is metal-free and can deliver a carbon footprint savings of up to 60% compared to aluminium-based structures.

NICOLA: PET-MET is the most popular structure on the market. On the plus side, PET-MET is a metallised material that offers a strong barrier and is a good option for delicate and mid-to-high value nuts. On the negative side, its metal content means it is not transparent, and its PET film means it's not recyclable.

KURT: Exactly. PET-MET became popular thanks its packaging performance, but now there are newer, more sustainable alternatives. We can easily deliver a transparent high barrier with the same performance. Of course, transparency is not a fit for all nuts. Foods with very high oil content or powdery and salty coatings may appear less “clean” in transparent packaging. For those products, if brands are looking to move away from PET-MET, fully printed metal-free barrier PP or PE packaging is an option, or even a semi-opaque window on metal-free packaging.

NICOLA: You mentioned a downside of PET-MET packaging is that it's non-recyclable. When we consider coming EU sustainability legislation, as well as sustainability pledges made by many brands and retailers, what is the future for PET-MET? And what are the alternatives?

KURT: You're correct, while PET-MET offers a strong barrier for nut products, it does not answer the increasing sustainability demands of consumers, brands and legislation. In order to bring more sustainable solutions to the nuts and dried fruits space, Amcor has developed a range of recycle-ready specifications that provide the right protection and brand presentation for nuts producers.

NICOLA: How can nuts producers compare recyclable vs. non-recyclable bags and pouches?

KURT: Which packaging is collected and sorted for recycling varies by country and sometimes by city, but what we see across Europe is a move away from PET and Alu based structures. This is because there is no recycling stream today for PET-based bags and pouches. The alternatives use different materials, such as PE and PP, which do fit existing recycling streams. Our team works to understand the different recycling infrastructures available across Europe and we have developed a portfolio of more sustainable packaging which includes: mixed PO, full PP, full PE and paper structures.

NICOLA: Material selection is a large part of the decision-making process, but other factors such as filling, transportation handling and the seal are also important considerations.

KURT: They are. You can never guarantee 100% exclusion of oxygen in the pack. Oxygen can be introduced by choosing the wrong packaging material of course, but it can also be a result of not optimising the filling machine settings or heavy handling during transport, in-store and after purchase.

The packaging material can have an extremely high barrier, but if you have lots of leakers in your seals, this is not bringing the required benefit. This is where there’s a huge benefit to working with technical experts, like our Field Technical Services team, who can help you set up your filling machine parameters for proper sealing to avoid air leaks.

An overview of barrier need by product type

This is a simplified guide to product requirements. Our experts on food protection, food packaging, and filling processes can help you to select the right material for your product and your filling machines.

Find out more about how AmLite metal-free laminates can help you create a premium look without compromising on freshness. Of course, barrier is just part of packaging selection – unique formats such as PushPop and opening/reclosing features also play a key role in product success.

Contact us to connect with our nuts and dried fruit packaging experts. Or find out more about our full offering for nuts, snacks and sweets packaging.

*Would you like to stay up to date on the latest industry trends? Sign up to receive regular information, invitations to webinars about sustainability, regulations and other current packaging topics. *