Researchers make edible cookies from old plastic bottles
Scientists in the United States have developed a surprising method that turns old plastic bottles into edible, protein-rich cookies, potentially offering a new way to tackle both plastic waste and food shortages.
Researchers at Southern Illinois University (SIU), led by Lahiru Jayakody, developed a process that uses modified microorganisms to break down polyethylene terephthalate, better known as PET. Instead of simply recycling plastic into new products, the researchers are attempting to convert its carbon into useful nutrients.
The process begins by chemically breaking down PET using water, oxygen, high temperatures and extreme pressure. This produces basic chemical components, including ethylene glycol, which genetically modified yeast can process. The yeast then converts these substances into proteins, fats and other useful compounds.
The researchers used modified strains of ordinary yeast, including baker’s yeast, whose DNA was adjusted so the microorganisms could process components derived from plastic. Old PET drinking bottles were combined with agricultural waste such as corn stalks and leaves during the experiments.
The resulting nutrients are mixed with ingredients such as fiber, starch and sweeteners before being turned into dough. A special 3D printer then shapes the mixture into small cookies known as “µBites” or “Micro-Bites.”
The project could have applications far beyond ordinary food production. Researchers see the cookies as a possible emergency food source for astronauts, submarines and disaster zones where access to fresh food is difficult. The idea originated from the NASA Deep Space Food Challenge, although the team did not ultimately win the competition.
The technology is still expensive, with production currently costing around $60 per kilogram. However, the researchers hope that more efficient yeast cultures will eventually bring the cost down. If successful, the unusual approach could one day transform plastic waste into a sustainable source of food.