Derived from renewable materials such as wood fiber from trees or plastic from sugarcane, bio-based packaging materials offer great opportunity for food and beverage companies. Granting longer product life, sustainability and other benefits, it is met with enthusiasm from both packagers and consumers.

Though sometimes challenging to make the transition to bio-based substitutes, it would be a surprise to find a food or beverage supplier who hasn’t at least tested it. Recent innovations are pushing the boundaries of sustainable packaging, and here are just a few solutions for consumers craving alternatives to traditional packaging.

Silk protein coating for longer fruit life

Produce is one of the first food groups to lose its luster after only a few days in the refrigerator – or on a shelf. Strawberries are notorious for being finicky, waiting to adorn a special dessert or just to be popped into one’s mouth.

Tufts University biomedical engineers may have the answer to the fast fruit-rot dilemma. Engineers found that fruits can stay fresh for more than a week without refrigeration if coated in an odorless, nearly invisible biocompatible silk solution. Fibroin, an insoluble protein found in silk, has the ability to stabilize and protect other materials while being fully biocompatible and biodegradable.

Fresh strawberries were dipped in a solution of 1% silk fibroin protein. After repeating the process, the coated fruit was treated with water vapor under vacuum (water annealed) to create varying percentages of crystalline beta-sheets in the coating.

The coated berries were stored at room temperature and dipped in varying numbers of coats of silk that had been annealed at different times and then compared with uncoated berries. Tests showed the silk coating prolonged freshness by slowing fruit respiration, extending fruit firmness and preventing decay.

Natural foods wrapped in natural packaging

A new 100% compostable wrapper by Sheffa Foods adorns its coffee house-inspired granola bars. Bio-based and renewable, the flexible package is designed to break down and fully return to nature, becoming part of the food waste stream.

Co-founder Leslie Angle believes that natural food products deserve natural food packaging. The new packaging material decomposes in controlled conditions in less than 180 days. If discarded in a landfill, it will break down like an orange peel and in a “reasonable amount” of time, compared to traditional plastic packaging that decomposes only after hundreds of years.

Multi-layer bioplastics cover cheese, pasta

AIMPLAS (aimplas.net) has coordinated the research to develop new sustainable packages extending the shelf life of cheese and fresh pasta within the framework of the European project BIO4MAP. The result has been a new generation of barrier, multilayer and transparent packages with a 25% lower cost than conventional ones, lower environmental impact and lower carbon footprint by up to 29%.

The layers of bioplastics (PLA, PVOH and adhesives) and a wax coating obtained from olive leaves has made possible, insulating the product from oxygen and humidity in order to avoid the growth of bacteria and fungi.

Ingeo-based films for flexibles

NatureWorks (natureworksllc.com) and Metalvuoto (metalvuoto.it) released a new line of high-barrier Ingeo-based flexible substrates designed to keep processed foods fresh on store shelves – specifically, for flexible packaging. Though used for years in fresh food packaging, this is the first application for longer shelf-life foods packaged in flat, stand up or square-bottom pouches.

The Metalvuoto film allows using a two-layer pouch with performance matching that of three-layer pouches. The Oxaqua coating technology claims to provide excellent barrier as well as heat seal-ability.

Industry Insights

by Scott Steele, president, Plastic Technologies Inc.

Although many brand owners are interested in reviewing their existing packaging to see how its environmental profile can be improved, there are several obstacles to taking it all the way to a bio-based material.

The biggest positive driver is the opportunity bio-based polymers present to brand owners to package products in materials that are as natural as the consumables they are protecting. With safety continuing to be a major consumer and governmental focal point, it is important to eliminate packaging components that might negatively impact the contents. Therefore, it’s logical that the ideal goal would be to package food products in material that is derived from other food products.

While many are drawn to the perceived advantages, there are additional considerations that have to be part of the evaluation process. For example, bio-based materials do not lend themselves to the current recycling classification. A material such as PLA, which could be considered a PET substitute, cannot be recycled in the PET waste stream. Instead of the readily understood #1 designation, it would be labeled a #7, creating a potentially negative recycling scenario. Clearly, this is not desirable for brand owners.

The availability and economic viability of bio-based materials are also a significant consideration. Because the demand for these resins is relatively low, supplies are also low. Without volume to drive down cost, it is frequently cost-prohibitive to entertain conversion to these materials.