Bioplastics made from upcycled food waste. Prospects for their use in the field of design

In recent years, the negative effects on the environment of the intensive use of synthetic, oil-derived plastics to make products, even those with a limited required duration, have given renewed impetus to the search for biodegradable and/or compostable materials obtained from renewable sources, particularly biopolymers derived from vegetable, animal or microbial matter that could prove a valid alternative in a number of applications: not only in the packaging industry, but also for making objects with a longer required duration. Indeed, as well as offering the possibility of being used as they are, immediately after having undergone traditional-type mechanical processing, it is also possible to mix, supplement and modify them both on a macro- and nanometric scale, allowing us to significantly increase their properties and performance and adapt them to a wide variety of needs. However, the real challenge is to create new materials from food waste and not from specially grown crops, whose production has, in any case, an environmental cost. This allows us to reduce the waste produced when processing foods, which is usually a practical problem and involves a considerable investment in economic terms. It also helps us address one of the worst problems of our time: that of the waste that sees a third of the food produced worldwide lost along the various steps of the food production chain. There is an enormous variety of vegetable, animal and microbial waste that can be used to create biopolymers: from the orange peels left over from fruit juice production to the grapes used to produce wine; from chocolate production waste to egg shells and prawns. We can extract the starches, cellulose, pectin, chitin, lactic acid, collagen, blood proteins and gelatin that form the basis of bioplastics from these materials, either extracting them directly or using mechanical or chemical processes. These are true ‘treasure troves’ of substances that can become useful materials thanks to processes of varying complexity. In recent years, the testing of substances made from food waste has increased significantly; the sheer abundance of raw materials that can be used to make them has encouraged institutional research, as well as an approach to project development that has been widely embraced by many young designers who craft these materials. Nevertheless, there is still no systematic record of the results achieved. This has slowed down their adoption, which in contrast offers enormous potential that is still almost entirely unexplored. This paper considers all aspects of these materials, starting with the most interesting experiments underway, and envisages possible future scenarios.