Xylitol, a white crystalline powder termed a sugar alcohol or polyol, is made in Finland from acid-treated fibers of birch wood by a chemical process. The process requires high pressure and temperature, an expensive catalyst, and extensive steps to remove byproducts. A biotechnological approach involving corn fiber should require less energy, says Leathers. Expecting that beet and cane sugar will remain much cheaper than xylitol made from the xylose in corn fiber, Leathers envisions that the future of the alternative sweetener lies in niche markets. Xylitol has one-third fewer calories than conventional sugar but about the same sweetening power.
Diabetics process it through the gut without involving insulin.
Researchers in the United States and abroad showed children's dental health improved if their chewing gum included xylitol. Leathers began to brighten the prospects for making xylitol in the United States from corn nearly 10 years ago. He found that one strain of Aureobasidium yeast, in a process called hydrolysis, released up to 20 percent of the xylose from corn fiber that was treated with alkaline hydrogen peroxide. Since then, he's found a mixture of Aureobasidium enzymes that releases up to 70 percent. He and his colleagues also developed a process using a strain of another yeast, Pichia guilliermondii, to convert the xylose into xylitol.