North Carolina State University researcher Dr. Christopher Daubert adds a protein-based powder to a beaker of water, tinted with orange food coloring. As he stirs in the powder, the water thickens, becoming the consistency of orange juice.
Daubert, assistant professor of food engineering, and other researchers in Department of Food Science, College of Agriculture and Life Sciences, are trying to perfect a powder to help people with swallowing disorders. Although the project began with a request from a local hospital that needed some assistance in measuring the viscosity of liquids served to patients with swallowing disorders, the research holds promise for other food applications as well.
Some hospital patients suffer from dysphasia, a disorder that makes it difficult to swallow ordinary liquids, and often these ordinary liquids flow into a patientís lungs during swallowing. Carbohydrate-based thickeners are commonly used to thicken drinks and soups for these patients, but the thickeners provide little nutritional benefit.
"Most patients with this problem are elderly and could become malnourished, creating additional health problems," Daubert said. "We wanted to have a protein to function as a thickener so we could add that to any beverage, hot or cold, and have it instantly thicken."
Doctoral student Heather Hudson has been working with Daubert to develop the powder because she was interested initially in developing a product to assist dysphasia patients. Dr. Allen Foegeding, food science professor with expertise in dairy proteins, helped Hudson learn how to develop whey protein gels using various heating times, temperatures and salts.
Hudson developed many different gels that were freeze-dried, then ground into a fine powder. But when added to liquids, most of the powders just sank to the bottom. Hudson decided to focus her efforts on gels in the neutral acidity range. But when she revisited a lower-acid gel, she found success: a whey gel powder that thickens liquids without heat and without continuing to gel the way gelatin does.
She continued her analysis in the Rheology Laboratory at N.C. Stateís Food Science Department, analyzing the powderís performance in hot drinks and acid liquids, and while stirring.
"It functioned very well. I think it could be used to thicken ice creams, yogurt and other dairy products."
Daubert and his colleagues believe the whey-based powder may serve other purposes, including use in popular health shakes. "We realize now there are a lot more uses for this than just thickening liquids for patients with swallowing disorders," he said.
As developed, this dairy powder would allow food companies to label products made with it as "all natural" or "all dairy," Daubert said. And unlike similar products, which continue thickening liquids after they are added, this powder stops thickening fairly quickly.
N.C. State University has applied for a patent on the whey protein powders. When researchers demonstrated the thickening powders at a Dairy Management Inc. meeting last summer, "a lot of people were interested because it is an instantaneous thickener," Hudson said.
Daubert says the researchers would like to see how their product will function in food systems, when compared with traditional thickeners.
Researchers still have some hurdles ahead of them in developing this product. The taste needs impovement, but Hudson said that is easily solved by adding flavors. Also, the process for creating the powder is very expensive, and researchers hope to find a cheaper process. The powder is now in the form of a whey protein isolate, and a whey protein concentrate would be more economical.