20 November 2023

Taking a bite out of plastic waste

A piece by Managing Associate Laura Clews has been featured in Volume 2 of the Sustainable Food Digest by Food Matters Live, giving an insight into patents related to environmentally friendly food packaging.

An extended version of the press release is available below.

Due to their low cost of manufacture, versatility and durability, plastics quickly became an established material for packaging food and drink products. However, there has been a growing concern around the disposal of these non-biodegradable materials. Food and drink packaging formed 83% of household plastic waste produced in the UK in 2022, and of the 2.5 million metric tons of plastic waste generated in 2021, only 44% was recycled. The remainder is typically sent to incinerators and controlled landfills, which do not provide a long-term solution for ever increasing amounts of waste.

Consumers are therefore calling for the use of more environmentally friendly packaging which can degrade without releasing toxins. Manufacturers must ensure that packaging material has sufficient strength to contain and protect the product through its transport, storage and distribution. In the food and drink industry, it is also imperative that materials do not leach any undesirable chemicals into/onto the product. Additionally, packaging must provide a suitable water vapour transmission rate (WVTR) and oxygen permeability coefficient as the amount of moisture and oxygen present can affect the shelf life of the product. Producing cost-effective packaging is also important as most consumers are only willing to pay a small premium for environmentally friendly products.

Fortunately, the food and drink industry has risen to this challenge and many new and innovative packaging materials have been developed in recent years.

Edible Packaging

The concept of edible packaging and containers is not new – Italo Marchiony’s patent directed to a mould for ice cream cups was granted in 1903. However, many of the latest developments in edible packaging have centred around nutritious seaweed. At the London Marathon 2019, runners were offered “Oohho” by Notpla, edible seaweed pouches filled with a sports drink, in a bid to replace 200,000 single use plastic bottles. The capsules can be bitten to release the liquid inside and if the consumer prefers not to eat the seaweed film, it will naturally break down within 4 to 6 weeks once discarded.

Notpla’s patent application (GB 2,612,816) teaches that the edible membranes are produced by extracting a cellulose polymer from seaweed which is then pumped through a die to create two ribbons or films. The desired liquid is then injected between the two ribbons/films which are subsequently sealed.

Evoware have also utilised seaweed to produce edible packaging, creating containers, straws, cutlery, and even edible Ello Jello cups. These are formed by hydrating seaweed to create a slurry which is then cast and dried in the required form (WO 2014/108887).

As an alternative approach to edible containers, Italian designer Enrique Luis Sardi produced a new coffee cup for Lavazza in 2003. The design comprised a pastry dough molded into the form of a cup and a patented icing sugar coating on the inner surface, creating a waterproof barrier whilst also sweetening the coffee it contained. The cookie cup can be consumed after use, which could eliminate some of the 2.5 billion disposable coffee cups used each year in the UK, and provide a delightful snack.

Other Food-Based Packaging

For most adults, coffee is not simply a drink choice, but an essential for day-to-day life. It has been reported that in the UK, 500,000 tonnes of used coffee grounds are produced every year, most of which ends up on landfill sites. Fortunately, Kaffeeform, has found a way to repurpose this waste, creating durable cups formed from recycled coffee grounds and other plant-based resources that are hardened with biopolymers.

Thermoplastic Cellulose

Some companies have turned to plant power to create environmentally friendly packaging materials similar to plastics, including VTT Technical Research Centre of Finland Ltd, who have developed a thermoplastic cellulose material.

As the most abundant renewable organic polymer, the use of cellulose as a packaging material is highly desirable. However, it cannot be thermally processed and is virtually insoluble in traditional solvents. In order to impart thermoplastic properties, modification of cellulose is required. In the patent application filed by VTT (WO 2016/193542), the physical and chemical properties of a thermoplastic cellulose material are achieved by decreasing the molar mass of raw cellulose using a hydrolysis process and a long chain fatty acid modification. The material formed can reportedly be moulded to a desired shape using heat and processed using traditional plastic treatment processes. These materials are reported to be mechanically strong, provide excellent WVTR properties, and good heat-sealability.

Polyhydroxyalkanoates (PHAs)

PHAs are a class of bio-derived, biodegradable polymers which have tuneable properties ranging from rigid-brittle to rubber. They are compostable thermoplastics, and include natural polyesters produced by bacterial fermentation of sugar, glucose, or vegetable oil feedstock. The versatility of PHAs makes them a suitable candidate for a wide range of applications, providing a viable alternative to fossil fuel-derived plastics. Cambridge Consultants have developed a range of food and drink containers and utensils formed from PHAs.

The global biodegradable packaging market reached over $440 billion in 2021 and is expected to continue to increase. In addition, the global consumable packaging market was valued at $697 million in 2016 and is on track to reach $1.10 billion in 2023. As the development of more environmentally friendly packaging materials has the potential to create significant revenue for manufacturers, it is unsurprising that companies at the forefront of this research are looking to protect their intellectual property in advance of any product launch.

Laura Clews
Managing Associate