
Read: more
details in Agricultural Research A New Sweetener from Ethanol
WasteBy Ben Hardin July 3, 2000Corn fiber thats left over from
ethanol production could be turned into a high-value, low- calorie sweetener
for niche markets, based on a process being developed by
Agricultural Research Servicescientists. The sweetener is a white crystalline powder called xylitol. Makers of some
specialty brand sugarless chewing gums now pay about $3 per pound for xylitol,
which gives their product a minty-cool taste. By comparison, industry now sells
the ethanol leftovers as cattle feed for only a few pennies per pound. The scientists found that certain strains of the yeast Pichiaguilliermondii can excel at making xylitol, but that process can be
hindered by glucose, another of the leftover sugars from fermented corn fiber.
The problem: When P. guilliermondii comes in contact with both glucose
and xylose in fermenting corn fiber, it prefers the glucose
and--like a child who would rather gorge on ice cream than spinach--it spends
its energy on gobbling the glucose, which leaves the yeast relatively
ineffective for carrying out the xylose-to-xylitol transformation. The solution
devised by ARS scientists: Send in the B team. The scientists add
an initial batch of P. guilliermondii to the fermenting fibers to devour
the glucose. Then they mix in more P. guilliermondii to tackle the task
of transforming the xylose into xylitol. Xylitol has one-third fewer calories than sugar and about the same
sweetening power. Its currently made in Finland in a chemical process by
treating acid-treated fibers of birch wood. Its now a $28 million market
in foods for special dietary uses, mouthwashes, toothpastes and chewing gums. Biological conversion of xylose should help make xylitol more economic to
produce, according to the researchers, because it requires less energy than
chemical conversion. This could drive production costs down and the market
volume up. An article about the research appears in the July issue of Agricultural Research magazine and
online at: http://www.ars.usda.gov/is/AR/archive/jul00/xylit0700.htm Scientific contact: Timothy D. Leathers and Badal C. Saha, ARS
National Center for Agricultural
Utilization Research, Peoria, Ill., phone (309) 681-6377 (Leathers), (309)
681-6276 (Saha); fax (309) 681-6686,
[email protected]
and [email protected]. U.S. Department of Agriculture |