Potato plastic is made from the starch of potatoes and water under high pressure and heat. Unfortunately, this material alone isn’t practical for most products so it is often blended into other bio-based or even petroleum-based plastics at ratios that companies don’t generally like to reveal.
More issues with potato-based plastic are evident with many other plant-based plastics in the need of fertilizer, large amounts of water, and often pesticides for a strong yield. There is also controversy around the usage of farmland for plastic instead of food. The argument is that we have all this land allocated to growing crops for energy and plastic materials yet there are still people starving every day.
Also, since this decreases the supply of land, food prices would rise, as we see in the case of corn and ethanol in the United States. Now you’re probably thinking, well the same can be said about any plant-based material. This is incorrect. If we look at the sugarcane ethanol industry in Brazil, we see a non-food crop being grown and harvested sustainably and maximizes the entire use of the plant. It is important to note however, this is only possible due to the advanced agricultural technology Brazil has developed to go along with its specific climate.
So can we create a sustainable way of manufacturing mass amounts of potato plastic for use? It’s possible in the future. However, due to the lack of practicality of potato plastic, it’s more likely this is developed for another crop before so.