Comparative Analysis of Shear and Extensional Rheological Properties of Tremella Polysaccharide with Commercial Thickeners for Dysphagia Management at Different IDDSI Levels

Research Findings

Abstract

Shear rheology and extensional rheology are key tools for developing thickeners for dysphagia food. This study selected Tremella polysaccharide (TP) and commercial thickeners including xanthan gum (XG), guar gum (GG), sodium alginate (SA), sodium carboxymethyl cellulose (CMC), and konjac gum (KGM), to compare their thickening performance at IDDSI levels 1-3 through shear rheology, extensional rheology, and droplet aspect ratio. The concentrations of the samples with similar shear viscosity at a shear rate of 50/s were successfully identified and used for the study. The shear rheology results showed that the shear-thinning behavior of XG, KGM, TP, and GG was more significant than that of SA and CMC, and at IDDSI level 2, the breaking time of TP and XG was relatively close. Additionally, syringe extrusion flow behavior tests indicated that XG and TP had larger droplet aspect ratios compared to other polysaccharides used in this study, showing higher cohesiveness. This study comprehensively explored the shear and extensional properties of TP and confirmed its tremendous application potential in developing dysphagia thickener formulations.

Keywords

Food oral processing; Dysphagia management; IDDSI; Extensional rheology; Polysaccharides

Highlights

1. The cost of preparing thickening liquid using TP is lower at the same IDDSI levels.

2. TP exhibits higher shear-thinning characteristics at the same IDDSI levels.

3. TP has better extensional rheology and cohesiveness compared to other thickeners.

4. TP has great application potential in developing dysphagia products.

Visual Appreciation

Research Conclusion

With the aging population, the demand for dysphagia diets is rapidly increasing. Individuals with dysphagia require appropriate texture modifications using thickeners to help safely swallow nutrients or medications. This study comprehensively compared the rheological properties of TP and commercial thickeners (XG, GG, SA, CMC, KGM), providing a basis for the application of TP in the development of dysphagia-friendly foods. The study concludes that for each IDDSI level, the ease of swallowing various samples differs, and the results of shear rheology and extensional rheology confirm the tremendous application potential of TP for developing dysphagia thickener formulations.

Moreover, this work can provide scientifically effective rheological knowledge to understand the flow behavior of different polysaccharide-thickened liquids. However, one of the main limitations of this study is the lack of clinical intervention effects using TP to reduce adverse functional outcomes for individuals with aspiration pneumonia, malnutrition, and dysphagia. Additionally, changes in food and liquid textures are considered the cornerstone of dysphagia management, and based on the principle of different inhalation risks between various dosage forms, this should be further explored in future research in this field.

Furthermore, fluid dynamics should be explored in the future through in vivo, in vitro, and computational modeling approaches, which can provide important knowledge in developing dysphagia-friendly foods to meet safety, nutritional, and sensory requirements.