Thesis Title

A Systematic Investigation Into the Effects of Carbonation on the Viscosity of Liquids

Date of Graduation

Spring 2006


Master of Science in Communication Sciences and Disorders


Communication Sciences and Disorders

Committee Chair

Lynette Goldberg


This investigation measured the effects of carbonation on the viscosity of four liquids: water, Coke, Sprite and Dr. Pepper. Viscosity was measured with each liquid in a carbonated and de-carbonated state, and then thickened with a starch- and gum-based agent to a nectar-like consistency. Manufacturers' recommendations for achieving the nectar-like consistency were followed. A total of 480 samples were analyzed using a Brookfield Dial Viscometer. Statistical analyses showed that carbonated thin liquids were significantly more viscous than de-carbonated thin liquids. In contrast, de-carbonated thickened liquids were significantly more viscous than carbonated thickened liquids. Under both thin and thickened conditions, the effects of carbonation varied according to the type of liquid. Mixing carbonated and de-carbonated liquids with the starch-based agent resulted in a significantly higher viscosity than when liquids were mixed with the gum-based agent. However, with one exception, all of the mean viscosities for thickened carbonated and de-carbonated liquids fell below the range for nectar-like consistency recommended by the American Dietetic Association. Results support the findings of Bülow et al. (2003) and suggest that the inclusion of carbonated thin liquids in the management of dysphagia could be a treatment option for adults with this disorder. The inclusion of thickened carbonated liquids also could be valuable. With either approach, clinicians need to pay careful attention to the varying effects on the interactions between carbonation, liquid type, and thickening agent.


dysphagia, carbonation, viscosity, thickened liquids, thickening agent base

Subject Categories

Communication Sciences and Disorders


© Jennifer Corbello