New Single-Use Tableware Biodegrades Fully in 60 Days

It's nice to dream of a zero waste world, in which people always remember to take their reusable containers to stores that happily fill them, and there are no heaps of plastic recycling to put out on the curb each week. While we should not stop striving for this ideal, it's unrealistic to think it will take over the world anytime soon. There will be a need for single-use, disposable containers for a long time yet, whether it's for hygiene reasons or on-the-go convenience.

That's where innovation can help. Designing truly biodegradable containers made from natural materials is a good workaround that could reduce plastic waste, and a group of scientists at Northeastern University in Boston has done precisely that. Led by Hongli (Julie) Zhu, the team has come up with a set of green tableware that is made from sugarcane pulp and bamboo. 

Sugarcane pulp, also known as bagasse, is the fibrous residue left over after crushing sugarcane to extract juice. It's a byproduct of the food industry and often goes to waste, so this gives it new purpose. The researchers wove it together with bamboo fibers to make a material that's both mechanically stable and fully biodegradable. From a press release:

"The new green tableware is not only strong enough to hold liquids as plastic does and cleaner than biodegradable [containers] made from recycled materials that might not be fully de-inked, but also starts decomposing after being in the soil for 30-45 days and completely loses its shape after 60 days."

Zhu confirmed with Treehugger that the tableware will break down in a backyard composter and does not require the intense heat of an industrial composting facility, as many so-called biodegradable containers do.

The tableware also contains alkyl ketene dimer (AKD), an eco-friendly chemical that is widely used in the food industry to improve resistance to oil and water and to ensure sturdiness when wet. "With the addition of this ingredient, the new tableware outperformed commercial biodegradable food containers, such as other bagasse-based tableware and egg cartons, in mechanical strength, grease resistance, and non-toxicity."

When asked if any softening occurred after prolonged or repeated exposure to a beverage, Zhu told Treehugger that the tableware remained fully intact after two hours. For the first 30 minutes it held boiling water, but this cooled over time, as any hot drink would. 

Even more impressive is this tableware's low carbon footprint. Its manufacturing process "emits 97% less CO2 than commercially available plastic containers and 65% less CO2 than paper products and biodegradable plastic." It's also substantially cheaper to produce, costing $2,333/ton compared to biodegradable plastic at $4,750/ton. The last hurdle is to make it more cost-effective than conventional plastic cups, which cost only $2,177/ton – but it's not too far off that goal.

Zhu told Treehugger that the tableware is well-suited to a range of one-time uses, from coffee shops, supermarkets, and mall food courts, to private parties and domestic use. She said in the press release, "It is difficult to forbid people to use one-time use containers because it's cheap and convenient. But I believe [a] good solution is to use more sustainable materials, to use biodegradable materials to make these one-time use containers."

It might not be a perfect zero-waste world, but having containers that can break down fully in one's own home composter is getting pretty close. 

Details on the new tableware will be released November 12 in the journal Matter.