2012 Volume 16 Issue 2 Pages 155-164
Using various thick foods as an index for the thickness of foods for dysphagia, when adjusting thickness by instant food thickeners (IFTs), is beneficial for clarifying the thickness easily, but may not be an appropriate means because of lack of objectivity. However, hospitals or institutions for the elderly do not usually use any instruments to measure the physical properties of thick foods such as a viscometer or rheometer because such instruments are expensive and require space. The Line Spread Test (LST) has been suggested to be a simple, inexpensive, and useful tool for measuring the rheological properties of thick foods. We measured physical properties of nine foods with various consistencies and those of thickened liquids prepared by nine commercial IFTs, and evaluated the suitability of the thick foods as indexes for the IFTthickening solutions. With data from thickened liquids and seven thick foods that were measurable by the LST, we performed cluster analysis and principal component analysis. They were roughly classified into three groups, and one of the clusters did not include IFT-thickening solutions. The other two groups could be further classified into six small groups. On the basis of these categorizations, the thickness standard could fall into three groups, and each group could be defined with the range of physical properties. We then performed multiple linear regression analysis on data from five index foods and IFT-thickening solutions made by one IFT, using the LST value as an objective variable, and the other physical properties as explanatory variables. A good multiple regression model was obtained when using viscosity and adhesive energy as explanatory variables, and all IFT solutions matched well in this model. These results indicate that the five thick foods in this study were suitable as index foods for IFT-thickening solutions on the basis of the physical properties including LST. In conclusion, using the LST standard for thickness will contribute to practical and useful standardization of diets for dysphagia, though it should be noted that some foods are not suitable for LST, which has some limitations on applicability.
