Allene Rosalind Jeanes
Listed among the ingredients of foods such as salad dressing, ice cream and canned soup is a substance called xanthan gum. This groundbreaking product and a process for producing it was discovered in the 1950s by chemist Allene Rosalind Jeanes, who died this day in 1995.
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Government chemist Allene Rosalind Jeanes (1906–1995) investigated bacteria that could serve as tiny living factories in fermentation vats to produce several important polymeric substances, instead of resorting to laboratory chemicals and the high temperatures and pressures often needed to effect polymerization.
With doctorate in hand, Jeanes went to work for the National Institutes of Health in Washington, D.C. After a few years she moved to the U.S. Department of Agriculture’s Northern Regional Research Lab (NRRL) in Peoria, Illinois. There she worked on polysaccharides (polymers made of thousands of sugar molecules).
Ani mportant discovery made by Jeanes and her team was xanthan gum, also a polysaccharide synthesized by bacteria. Xanthan gum is good for thickening ice cream and other foods. It also keeps foods like oil and vinegar from separating. If you shake a bottle of salad dressing, the oil and vinegar will appear to mix, but the oil does not truly dissolve. In time, the two substances will separate again. But with xanthan gum added, the oil and vinegar will stay together long enough to get from bottle to plate. Xanthan gum is found in everyday products from ketchup and steak sauces to cough syrups and skin lotions. And the petroleum industry uses huge quantities of xanthan gum to thicken the drilling mud that carries solid materials up to the surface.
Visit Chemistry in History to learn more about Allene Rosalind Jeanes.
Excerpted with permission, Chemical Heritage Foundation
www.chemheritage.org