High-barrier packaging has established itself in the food and beverage sector, despite being costlier, because it can prevent oxygenation and thus degradation of contents. Consumer trends around the world will continue to propel such packaging forward, but recycling of multilayer structures remains problematic.
As plastics continue to grow in packaging, concerns have arisen about their ability to protect the quality and safety of products from degradative effects. Therefore, the need for packaging materials that give even greater protection to packaged contents, particularly in the food and beverage sector, has seen a marked increase.
As a result, numerous barrier packaging technologies have been commercialized, preserving, protecting, and optimizing product shelf life. Many also have reduced the need for preservatives, provided packaging transparency and gloss, and served as printing substrates. Without such barrier packaging, perishable goods such as food, beverages, and pharmaceuticals would be susceptible to a wide range of deterioration processes.
Therefore, barrier packs have begun to replace more traditional pack types. But challenges remain for the high-barrier packaging films industry.
Replacement of Rigid Pack Formats
Consumer and technology trends have contributed to a gradual decline of rigid pack formats, in the face of flexible packaging and barrier films, over the last decade or so. Busier consumer lifestyles and the consequent demand for convenience products, together with the popularity of microwave cooking, have, for example, contributed to the growth of microwaveable retort ready meals packed in trays and stand-up pouches.
The market for stand-up pouches (SUPs) has grown, due not just to their replacement of plastic and glass bottles and cans but also to SUPs’ ability to reduce packaging costs while providing greater convenience for consumers. Stand-up pouches are lighter and have lower material use compared with rigid containers.
Heat-resistant retort stand-up pouches are made of laminated plastic films or foil if microwaving is not required. They can be filled, heat-sealed, and sterilized by pressure cooking in a retort (autoclave). As a result, retort pouches contain heat-treated, cooked food that is safe from microorganisms and has an ambient shelf life similar to tinned food. In addition, due to the packs’ thinner dimensions, food takes less time to cook in a flexible pouch than in rigid packaging such as cans and jars.
Foods currently using retort stand-up pouches include ready meals, soups, rice, vegetables, and sauces. However, despite their inherent benefits, there have been some obstacles on the way to widespread adoption of the packaging technology.
Responsible for keeping packaged contents fresh, barrier packaging itself is susceptible to degradation, and it is restricted by recycling problems and cost. Ethylene vinyl alcohol (EVOH) copolymer, for example, is water sensitive because absorption of atmospheric moisture reduces its barrier properties against oxygen and carbon dioxide.
Packaging-to-packaging recycling also becomes a problem with multilayer structures containing more than one type of plastic. While multilayer structures are difficult, or even impossible, to recycle mechanically, they can be recycled to energy or fuels by incineration, anaerobic pyrolysis, or plasma pyrolysis.
There is mounting public pressure on brands and retailers to reduce the environmental impact of packaging. Food and beverage manufacturers are also responding to consumers’ environmental concerns by reducing the amount of polymer to lower the pack weight — but not pack performance. Lightweighting continues, too, as part of the drive to reduce production costs.
Some companies are taking the need for sustainability one step further by creating biodegradable and renewable cellulose-based barrier films. Innovia Films and Sappi, for example, have combined their individual compostable substrates — Innovia’s NatureFlex and Sappi’s Algro Nature — to provide a packaging solution that offers the potential for either industrial or home composting or anaerobic digestion. Both NatureFlex and Algro Nature are manufactured from wood sourced from managed forests. According to the companies, these natural materials provide the essential barrier requirements for coffee, snack bars, and single-serve drink packs.
Barrier film producers often state that their products will play a vital role in more sustainable packaging. Many argue that barrier films are more environment-friendly because they help packagers use lighter plastics to replace much heavier materials such as glass, metal, and rigid plastics, thereby requiring less energy to transport products.
High-barrier packaging film demand is benefitting from the growing market share of the large retail chains. These chains have expanded the market for packaged food, with their focus on cost reduction and shelf-life extension. Retail chains have dominated retail food and drink markets in advanced countries for many years, but supermarkets/hypermarkets are spreading in many major cities in developing countries and taking a growing share of food and drink consumption.
International retail chains are also expanding their presence in developing markets, which will further expand barrier packaging demand into countries as they bring more consumers into contact with Western shopping patterns. Supermarkets/hypermarkets are becoming especially favored due to their wide product ranges and diverse choice of premium brands, usually unavailable in other types of outlets. There also has been growth in the number of discount stores and private-label products, which enable those on smaller incomes to purchase packaged food and drink at more affordable prices.
Smithers Pira is the worldwide authority on packaging, paper and print industry supply chains. Established in 1930, the company provides strategic and technical consulting, testing, intelligence, and events to help clients gain market insights, identify opportunities, evaluate product performance, and manage compliance. To find out more about high-barrier packaging films, see The Future of High Barrier Packaging Films to 2019.