Review of the effect of amylase-resistant dysphagia products on swallowing safety

Getting the consistency right in thickened liquids using Viscgo Sticks: A validation study

BACKGROUND

Dysphagia is a condition whereby a person's ability to swallow, eat and drink is impacted. One strategy to manage dysphagia and aid safe swallowing is the modification of food and drink, including using thickening agents to thicken drinks. Drinks are thickened to levels appropriate to a person's swallowing abilities and the underutilised 'syringe flow test' is currently the recommended method for checking thickness levels. Viscgo Sticks were developed as a practical alternative to the flow test.

METHODS

This is a real-world validation study designed to determine validity and reliability of Viscgo Sticks. Independent researchers and healthcare professionals tested Viscgo Sticks (Viscgo Limited) against the flow test in three levels of thickened drinks. Researchers also conducted tests with different thickening agents and different drink types: water, milk, orange juice and hot tea.

RESULTS

The intra- and inter-rater reliability of Viscgo Sticks was moderate to almost perfect (κ = 0.45-0.98) within and between researchers and substantial (κ = 0.66-0.67) within and between healthcare professionals. When tested by researchers and healthcare professionals against the flow test, Viscgo Sticks correctly classified 83.33%-100% of thickened drinks with high accuracy (area under curve = 0.70-1.00).

CONCLUSIONS

A simple and reliable tool like Viscgo Sticks, which can verify a prescribed thickness level of liquid, is invaluable in healthcare settings where day-to-day drink preparation occurs. Overall, Viscgo Sticks provide a reliable and valid means to test thickened drinks in clinical practice with a few exceptions identified.

Effects of Calcium and pH on Rheological Thermal Resistance of Composite Xanthan Gum and High-Methoxyl Apple Pectin Matrices Featuring Dysphagia-Friendly Consistency

High-methoxyl apple pectin (AP) derived from apple was employed as the main ingredient facilitating rheological modification features in developing dysphagia-friendly fluidized alimentary matrices. Xanthan gum (XG) was also included as a composite counterpart to modify the viscoelastic properties of the thickened system under different thermal processes. The results indicate that AP is extremely sensitive to thermal processing, and the viscosity is greatly depleted under a neutral pH level. Moreover, the inclusion of calcium ions echoed the modification effect on the rheological properties of AP, and both the elastic property and viscosity value were promoted after thermal processing. The modification effect of viscoelastic properties (G' and G″) was observed whne XG was incorporated into the composite formula. Increasing the XG ratio from 7:3 to 6:4 (AP:XG) triggers the rheological transformation from a liquid-like form to a solid-like state, and the viscosity value shows that the AP-XG composite system exhibits better thermal stability after thermal processing. The ambient modifiers of pH (pH < 4) and calcium chloride concentration (7.5%) with an optimal AP-XG ratio of 7:3 led to weak-gel-like behavior (G″ < G'), helping to maintain the texture properties of dysphagia-friendly features similar to those prior to the thermal processing.