February 2025 IDDSI e-bite

Testing, Testing, Testing…The importance of using testing methods with IDDSI levels

We know many of you are well acquainted with the various IDDSI Testing Methods, however it is important to continue using the tests rather than taking shortcuts by “estimating or eyeballing” thickness which could be inaccurate and potentially dangerous for individuals with dysphagia. Food and drink ingredients and textures vary, so it is not reliable to list foods that you think meet the criteria for a particular IDDSI level as they may be different at a later time or temperature. Also remember that it is important to test at the point of serving.

What is the IDDSI Flow Test?

• The IDDSI flow test is designed to test the ability of a liquid to flow in conditions related to swallowing a bolus. The thickness level of the liquid is defined by the amount of fluid remaining after 10 seconds using the IDDSI Funnel or alternatively, a 10 ml syringe of the correct dimensions (see below).
• The test is suitable for IDDSI Levels 0-3. Level 4 liquids do not flow so the fork-drip and spoon-tilt tests are used to differentiate between a Level 3 (moderately thick/liquidized) and Level 4 (extremely thick/puree).

Why does the IDDSI framework not give values of viscosity for textured modified products?

The IDDSI framework does not use viscosity values for identifying texture modified products for the following reasons:

• It’s not scientifically correct: Viscosity is used to describe Newtonian liquids (e.g. water, oil) however that does not apply to almost all thick drinks, which instead have non-Newtonian behavior. Their “apparent viscosity” depends on how they are tested.
• It’s not specific enough: Two different liquid types (e.g. gum-thickened drink vs nutritional supplement) with exactly the same measured viscosity at one particular test shear rate (e.g. 50 /s) will not have the same measured viscosity at any different test shear rates. Nor will they necessarily appear the same or behave the same way when swallowed.
• It is not practical: Specialized, expensive equipment is required (e.g. rheometer / viscometer with cone-plate attachment) which is not available in health and community care settings.
• In comparison, the IDDSI Flow test is inexpensive, accessible and easy to perform requiring only the IDDSI Funnel or a 10 ml syringe and timer.

Is the IDDSI Flow Test accurate?

• Yes, in tests performed by the research community and international medical products industries, the IDDSI flow test has been demonstrated to be accurate and reliable [1]. "Validation of the IDDSI funnel for liquid flow testing”
• The IDDSI Flow Test is based on the Posthumus funnel concept which has been used for many decades in the dairy industry to audit the thickness of milk, cream, yoghurt & custard. The geometry of the funnel or syringe allows for both shear and elongation flow types which represent flow conditions within the oral cavity and pharynx [2]. "Experimental and Computational Investigation of the IDDSI Flow Test"

Why was the IDDSI Funnel developed? After the launch of the framework and testing methods, which introduced the IDDSI flow test using a 10 ml syringe of specified dimensions, the IDDSI Board of Directors were made aware that the required 10 ml syringe was not available in all locations around the world. The IDDSI Funnel was conceptualized, developed and then tested extensively to ensure it met the specification needed for the flow test to be performed reliably. In 2022, the IDDSI Funnels were ready for general use and made available to the global IDDSI community through a variety of sources. IDDSI Resources-Funnels

If I am using a syringe, can I use any 10 ml syringe? ·

• No, the correct types of syringes are listed on the IDDSI website.
• It is important that the barrel of the 10 ml syringe meets the correct dimension as barrel sizes and shapes of different 10 ml syringes can vary (even though the Luer-tip nozzle is ISO-standardised). The 0-10 ml measure on the syringe should be 61.5 mm in length.
• Check to make sure that there are no defects or blockages in your syringe: 10 ml of plain water should drain completely through the syringe in 7 seconds.

We hope you found this refresher on the IDDSI Flow Test helpful. Watch for more testing methods which will be discussed in our future e-bites. Remember too that you can visit our website and check out our many resources. IDDSI Resources

Communications Survey results: Thank you to all of those who completed the survey about our communications and specifically the e-bites which bring you IDDSI news and updates.

We are very pleased that most individuals would like to continue receiving a  monthly ebite. We also appreciate your feedback regarding topics and content of most interest which include, information about our education opportunities, particularly webinars, and information about our framework. We will be incorporating your feedback into our future communication plan.    

IDDSI Events

Early Bird registration is now open for the

US IDDSI Symposium in beautiful Newport Beach, CA!

Friday, July 25th, 2025

For more details visit the US IDDSI Symposium Event page

SAVE THE DATE:

UK IDDSI Academy Pilot

September 16th, 2025

St. Michael’s Centre, Bristol, UK

Details will be available on the IDDSI website very soon!

SAVE THE DATE:

Australia IDDSI Expo and Academy Pilot

October 20th and 21st, 2025

Victoria Park, Brisbane, Australia

Details will be available on the IDDSI website very soon!

Sponsors

We are excited to announce our new Silver Sponsor, GentleFoods.

GentleFoods® crafts nutritious, moulded puréed meals with authentic Asian flavours, ensuring safe, familiar, and visually appealing dishes for those with swallowing difficulties.

We would like to thank Campbell's Food Service for upgrading from Silver Sponsor to Gold Sponsor.

Campbell’s Foodservice is a healthcare market leader in providing a full range of creative menu solutions, soups, entrees, healthy beverages and, texture modified products.

Global Updates

Brazil: The nutrition and speech therapy team at Unimed Natal Hospital, located in the northeast of Brazil, recently brought in Dr. Cynthia Godoy, Brazil IRG co-leader to discuss IDDSI implementation. The hospital was seeking information and support on how to implement IDDSI standards for their new unit. It was an exciting and important meeting for the team as they strive to ensure safety for patients experiencing dysphagia. 

Canada: The Canada IRG's motto for 2025 is, IDDSI “Better, to Best Practice, One Step at a Time! Read the February Can-Do newsletter for all the details on the CIRG webpage

United States: The February USIRG Newsletter reminds you to connect with IDDSI on Instagram and LinkedIn, where you can find tips on IDDSI implementation, new IDDSI updates, global and US IDDSI presentations/conferences, and more!

Read all the newsletter details here on the USIRG webpage

If you have any suggestions for webinar topics, we’d love to hear them! Head over to our Contact Us form, choose subject “Webinars”, and let us know what you’d like to see in the upcoming months. 

Upcoming Events:

• German Society for Swallowing Disorders, Würzburg, DE, Mar 19-21, 2025
• Dysphagia Research Society Conference, Philadelphia, PA, Mar 25-28, 2025, https://www.dysphagiaresearch.org/page/2025-Annual-Meeting
• FOP - Food Oral Processing Conference, Valencia, SP, May 12-14, 2025
• The 33rd World Congress of the IALP is coming to Malta August 24-28, 2025 - Innovation and inspiration in Communication Sciences and Disorders Congress Topics and Registration Information
• ESSD - European Society for Swallowing Disorders Conference, Athens, GR, Nov 7-11, 2025