Beet pulp lives on in packaging
Scientists turn sugar beet pulp into packaging material
By JOHN O'CONNELL
Researchers have incorporated the pulpy byproduct of sugar beet processing into a biodegradable plastic that holds promise for use in disposable packaging.
Washington State University professor Jinwen Zhang, a polymer expert, collaborated with chemist LinShu Liu and plant physiologist Arland Hotchkiss, both with the Agricultural Research Service's Eastern Regional Research Center in Wyndmoor, Pa.
Zhang explained sugar beet pulp is extremely porous, making it ideal for mixing with a polymer that fills in the pores.
The researchers began their project five years ago and recently published their findings.
The product is a thermoplastic that softens and can be molded when heated and hardens when cooled. Zhang said its production can utilize concentrations well above 50 percent sugar beet pulp. According to USDA, the product has mechanical properties similar to polystyrene and polypropylene.
Zhang said his team has collaborated with the Wisconsin-based packaging company Berry Plastics, which helped fund some of the research and may seek to put the product to use. A spokesman with the company declined to comment.
"It uses agricultural residues. That is sustainable. It's green, and it might be cheaper," Zhang said. "I think it has a potential there, but like with many bio-based polymer materials, manufacturers will influence the final fate of the material."
Mark Duffin, executive director of the Idaho Sugarbeet Growers Association, said the industry is always seeking new uses for its byproducts, and as a biodegradable substance, the pulp-based plastic could have a marketing advantage.
The main use for pulp currently is as a livestock feed. Duffin recalled in 2008, when Idaho had a light sugar beet crop, dairies called repeatedly wondering why they couldn't get more pulp. He said another important use for pulp is as a source of betaine, a naturally occurring chemical compound in plants, to enhance nutritional value in fish food.