USDA Scientists Turn Hide-Tanning Waste into
November 23, 1998
WASHINGTON, Nov. 23, 1998--Using a common laundry detergent enzyme,
U.S. Department of Agriculture researchers
are turning shavings from cattle hide tanning into a high-value protein that
can be used in a range of products, such as adhesives and packaging films,
Agriculture Secretary Dan Glickman announced today.
This is an innovative process that puts to good use a waste product
that now must be hauled off to landfills at a price, Glickman said.
It is a discovery that is good for our environment and our economy.
From 100 pounds of cattle hides, a tanner gets only 50 pounds of
leather--and 50 pounds of waste. Tanners use non-toxic chromium-III sulfate in
tanning hides into leather. Then they shave the bottom sides of chromium-tanned
hides to give them a uniform thickness. Each year, about 60,000 metric tons of
shavings end up as waste bound for landfills.
Agricultural Research Service
chemists Maryann Taylor, Eleanor Brown and William Marmer were able to break
down the chrome shavings with alkaline protease, an enzyme from a common
laundry detergent. The researchers first product was a low-value protein
hydrolysate that can be used in fertilizer. By modifying the process, they
produced a high-value grade of gelatin protein that is ideal for making
adhesives, industrial films for packaging, and encapsulating agents for
industrial and agricultural chemicals. The higher-grade product is equal--and,
in some cases, superior--to commercially produced gelatins. The scientists have
been granted two patents for their research.
Taylor also purified the chromium left over after the proteins were removed
and reused it as an agent in the tanning process. The quality of leather
produced was comparable to that of commercially tanned leather. She even found
a way to recycle the enzyme used to liberate the proteins.
ARS, USDAs chief research agency, operates a pilot tanning plant, the
only public facility of its kind in the United States, at its
Eastern Regional Research Center in
Scientists from Spain collaborated on part of the research. A modified
version of the process is now being used in a tannery in the Czech Republic.
ARS has also signed a cooperative agreement with ATO-DLO, a Dutch institution,
to develop applications for the protein products.
More information about the research is available on the World Wide Web at:
Scientific contact: The scientists at the Hides, Lipids, and Wool
Research Unit, Eastern Regional Research Center, Wyndmoor, Pa. William N.
Marmer, phone (215) 233-6585, email@example.com; Maryann M. Taylor,
phone (215) 233-6435, firstname.lastname@example.org; Eleanor M. Brown,
phone (215) 233-6481, email@example.com