You know that remaining liquid in your meat packaging once you’ve taken out a piece of meat? It isn’t a nuisance just for you, it’s actually a major issue in the world of fresh food packaging.
Because raw meat products require high standards of packaging for hygiene reasons, detachable plastic pads have been added to absorb these juices, extending shelf life and reducing an unappealing appearance. However, the extra layer of absorbent padding in the packaging actually makes it harder for the trays to be recycled: they are often glued to the packaging and must be manually removed. They’re also completely non-recyclable and actually also add additional cost and labor to the packaging industry.
In the United Kingdom, around 800,000 tons of meat packaging plastic waste is produced each year. And 5% to 8% of it comes exclusively from this absorbent padding. Some other alternatives have been produced, such as polymeric foam trays with open-cell structure, but the recycle-ability issue still stands.
Syrian student, Alaa Alaizoki, candidate for an Engineering Doctorate at Swansea University, has developed an innovative solution to the problem. Creating a new type of 100% recyclable meat packaging tray that could save thousands of tons in plastic waste, his new meat tray eliminates the need of a separate piece of absorbent plastic padding underneath entirely while still meeting the highest required standards and allowing consumers to look at meat from all angles through clear plastic.
The research was conducted as part of Swansea University’s COATED M2A programme, which provides industry-led research training for postgraduates in functional industrial coatings technology.
His investigative work focused on capillary recesses integrated into PET packaging film, with “targeted plasma treatment of the recesses to enhance their liquid retention capacity.” In the studies, even after 60 days, the plasma-treated recesses maintained their retention capabilities. After successful trials, he demonstrated alongside some of his colleagues that applying plasma treatment in food packaging can effectively isolate any excessive “juices”.
Mr. Alaizoki’s tray actually retains the juices itself through specifically designed and manufactured small-scale well cavities at the base of the tray that allow the meat juices to be trapped inside the same cavities. The novel tray ensures that the juices stay in place during storage or transport, and don’t flow out again. The advanced packaging developed can be washed under a tap, meaning the plastic is chemically and biologically safe to be recycled along with other household items. The lead researcher added that the new packaging product could easily help cut the amount of plastic going to landfill.
In his paper “Effect of plasma treatment on improving liquid retention capacity of capillary recesses for food packaging applications” with co-authors Christopher Phillips, David Parker, Craig Hardwick, ChrisGriffiths and David e Deganello, Alaizoki explains the physics behind the creation: “Additional components such as absorbent pads and foams present a problem in terms of recycling of the packaging film since soaked pads and foams are non-recyclable […]
Further, food trays with integrated micro-capillary features to act as a soak-away is an alternative solution used for retaining the food exudate. […] These capillary features have small sizes and suffer with other absorbent packaging solutions from limited absorption capacity.
“Capillary wetting (capillary phenomenon) is fundamentally based on capillary forces, which defines the spreading of a wetting liquid on a solid surface even against gravity. Liquid in open capillary systems is commonly controlled by introducing capillary burst valves on their capillary channels. This includes geometrical valves with a sudden change in their dimensions or hydrophobic valves, which are based on variation of surface wettability. The capillary valve has a pinning effect on the liquid meniscus generating a pressure barrier as the meniscus adapts to the change in valve geometry or surface wettability.
“The valving functionality was also studied for liquid trapping in closed capillary systems such a closed tube during vertical orientation and inclination. The liquid tends to drain from the open end of relatively large tubes by air finger propagation called Taylor fingering phenomenon. However, liquid drainage can be prevented for sufficient pinning effect and stable meniscus on the tube opening acting as a capillary valve. This mechanism can be extrapolated to the capillary recesses used to trap exudate in food packaging. Therefore, the pinning effect can be enhanced for larger capillary recesses within the food packaging tray to increase their retention of meat exudate.”
The groundbreaking new packaging has been patented and is already being used for meat products in the UK and across Europe. In fact, Alaisoki has partnered with packaging manufacturers Klöckner Pentaplast, and the design is already being used by leading UK food suppliers and retailers, such as Sainsbury’s and Asda. “I am very pleased to see results of my research already in action by Klöckner Pentaplast; reducing waste, helping reduce the environmental impact. It has been great to work with the company and the whole research team. I really appreciate their pro-active attitude towards environmental issues,” Alaisoki said about the partnership.
Alaizoki has stated that he believes that the technology could be used in other areas, like nappies or sanitary towels, by drawing in moisture and converting it into a gel which cannot physically leak back out. “You can turn it upside down, shake it, drop it, but the physics of the fluid mean that until it’s flushed out there is no way of the juices escaping. Physics is physics, it doesn’t matter if it’s food packaging or any other product,” he said. “This has the potential to be used in nappies and sanitary products, which also currently go straight into landfill, and take thousands of years to break down with the current gel technology.”
Mr Alaizoki has added in almost every single interview how pleased he was to be able to give something back to the country which took him in: “Swansea has supported my learning, and given me the opportunity for me to fulfil my potential.I have a wife and child here now, and it feels like home, even though the majority of my family are still back in Syria. I’m just so glad to have come up with an invention which is going to improve the lives of everyone in my adopted home.”
Sources:
https://www.sciencedirect.com/science/article/pii/S2214289421001277
https://www.circularonline.co.uk/news/100-recyclable-meat-tray-could-cut-food-packaging-waste/
