Episode Details

Brewing a Greener Future

Ever wonder where your used coffee grounds go after they’ve been completed? Probably not. But at South Dakota State University, researchers are turning them into something entirely unexpected: plastic. Not just any plastic, but a biodegradable alternative to oil and gas-based plastics that dominate the industry today. This innovative approach not only tackles the issue

of food and other biomass waste but also addresses the plastic industry’s reliance on fossil fuels and the rampant plastic pollution that harms both planetary and human health.

The Pervasiveness of Plastic

The vast majority of plastics are currently made from natural gas and crude oil, types of fossil fuel. As of 2019, this production process was responsible for 3.4 percent of the world’s total greenhouse gas emissions. Moreover, humanity produces over 300 million tons of plastic each year, resulting in widespread plastic pollution with adverse effects on both the environment and human health. Despite masquerading as a solution to excessive plastic waste, traditional plastic recycling is often ineffective due to contamination and industry deception. Thus, most plastic waste is diverted to landfills. Fossil fuel-based plastics take hundreds to thousands of years to decompose, and when they finally do, they release microplastics into the environment, which can infiltrate human bodies. 

Recognizing the need for a solution to this plastic crisis, Dr. Srinivas Janaswamy, the lead researcher, initially experimented with making biodegradable packaging using various agricultural byproducts, such as avocado peels, corn, oats, and wheat stalks. His focus has since shifted to spent coffee grounds, which contain lignocellulosic fibers — natural plant polymers essential for creating biodegradable plastics. The process of transforming coffee grounds into biodegradable films is quite intensive and involves drying, bleaching, and extracting the plant fibers from the coffee grounds. The resulting clear solution is then dried to form a strong, plastic-like film that can be used as a sustainable alternative to traditional plastic packaging.

A Second Life for Coffee Grounds

One of the significant advantages of this solution is its potential to reduce greenhouse gas emissions from fossil-fuel-based plastic production and minimize plastic pollution. But on top of that, it provides a sustainable method of reusing otherwise wasted coffee grounds. Every morning, millions of people worldwide begin their day with a cup of coffee, a ritual shared by over 60% of Americans. Widespread enthusiasm for this caffeinated beverage has propelled it to become the second most traded commodity globally by volume, just behind oil. As a result, coffee shops are ubiquitous, generating an enormous am