A team of scientists is working with the Starbucks coffee chain to develop a bio-refinery process that would convert the company’s discarded coffee grounds and day-old bakery goods into a key ingredient for making plastics and other products. The process, which will be described at a meeting of the American Chemical Society, builds on existing technology that converts corn, sugar cane, and other plant-based products into the ingredients for biofuels and other consumer products. According to researchers, the process involves blending the bakery waste with a mixture of fungi that breaks down carbohydrates in the food into simple sugars. They are ultimately converted into succinic acid, a material that can be used to make a range of products, including plastics, detergents, and medicines. While most experts say using crops for such purposes would not be sustainable, targeting food waste is an attractive alternative, said Carol S. K. Lin, of the City University of Hong Kong, who was leader of the research team.