Professor Dr. Markus Schmid is the director of the Sustainable Packaging Institute (SPI) at the Albstadt-Sigmaringen University of Applied Sciences. The SPI aims to support all players in the packaging industry along the entire value chain on their way to a more sustainable, circular bioeconomy. In an interview with afz, he talks about what such packaging could look like in the future.
Packaging with less plastic is not automatically more sustainable, Schmid says. Basically, he says, there is a lack of scientifically comprehensible assessments and comparisons of what constitutes more sustainable packaging. “The main function of any packaging is to effectively protect food. Food waste at the end of the value chain is a much bigger problem for sustainability. Tailored and well-designed packaging solutions can help prevent some of this food waste by ensuring the longest possible shelf-life.”
The “environmental footprint” of packaging, i.e. CO2 emissions as well as the consumption of water, energy and raw materials during production, is significantly lower compared to the one of the meat that is packaged in it. Schmid cites examples. “For a rump steak, 99.5 percent of the CO2 equivalents are associated with the meat and only 0.5 percent with the packaging. So if you throw away just one piece of steak, the waste is already as great as the entire packaging. On average, the ratio for food is 90:10, so the packaging accounts for a tenth.”
20 Percent of Meat Products are thrown away
Good packaging is sustainable, he says, if it improves the shelf life and safety of high-quality meat and sausage products and curbs food waste. “If we double the relative shelf life from one week to two weeks, we reduce retail waste by an average of 40 percent”, he said. That's why paper alone, for example, hasn't caught on, because if the functionalities aren't sufficient, we end up with shorter shelf lives, such as freezer burn in the case of frozen vegetables. We can't afford that with valuable foods," says the expert in an interview with afz. Currently, for example, 20 percent of meat products and sausage are thrown away. “We also have to change that with improved packaging.”
Schmid expects that intelligent and active packaging will soon be found on refrigerated shelves. For example, to determine the best-before date, these packages could also detect the ambient temperature and dynamically include it in the shelf life information. As a result, fewer expired goods would have to be disposed of and less food would be thrown away.
The food technologist is also conducting research on bio-based packaging materials such as so-called polylactic acid (PLA) films. To meet the requirements for packaging more sensitive foods, such as cheese and cold cuts, the barrier properties of PLA must be increased. To achieve this goal, Schmid's team is producing thermoformed trays from a composite with PLA as the main component in the PLA4MAP research project. The challenge here is to develop a biobased composite of PLA and a sealing film made of coated proteins and waxes. These are necessary to increase the gas and water vapor barrier properties. This is because to enable the use of modified atmosphere packaging (MAP), corresponding gas permeabilities must not be exceeded in the areas of oxygen and water vapor. “To ensure recyclability, we are also evaluating the developed packaging in terms of its mechanical and solvent-based recyclability”, he explains in the afz interview. The scientist would also like to involve large companies from the food industry in the project.
