CHAMPAIGN, Ill. -- The quest to satisfy the sweet tooth without adding to the waistline has a new weapon in its arsenal: a strain of yeast that can metabolize lactose, the sugar in dairy products, into tagatose, a natural sweetener with less than half the calories of table sugar.
Yong-Su Jin, a University of Illinois professor of food science and human nutrition, led the research team that engineered the yeast strain, which produces tagatose in much larger quantities than traditional enzymatic manufacturing techniques and could help make tagatose a cost-effective alternative to sugar or high-fructose corn syrup.
The glycemic index of tagatose is 3, which is much lower than that of sucrose, 68, and fructose, 24.
As such, tagatose carries a lower risk for developing Type 2 diabetes and other diseases caused by rapid and repeating glucose increases in blood."
In spite of its benefits, tagatose has a high manufacturing cost that has kept it from wide commercial use, Jin said.
Thus, when the yeast is fed lactose, its own metabolism drives it to produce a solution that is 90 percent tagatose - much higher than the 30 percent yield from traditional manufacturing.