Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management

Ömer Faruk Yaşaroğlu; Ayşe Kübra Söyler; Emre Cengiz; Şenay Demir Yazıcı

doi:10.58563/dkyad-2026.93

TR EN

Yutma Bozukluğu Yönetiminde Kullanılan Kıvam Artırıcıların Duyusal ve Akış Özelliklerinin İncelenmesi

Abstract

Amaç: Bu çalışma, yerli ve ithal üretim kıvam artırıcıların duyusal özelliklerini karşılaştırmayı ve akış özelliklerini incelemeyi amaçlamaktadır. Yöntem: Beş ticari kıvam artırıcı (ithal; Thicken Up Clear, Thicken Up tozu, Nutilis Clear, Nutilis Tozu ve yerli; PraThick), tanelilik, yapışkanlık, kayganlık, yutma kolaylığı ve oral rezidü gibi duyusal özellikleri açısından değerlendirildi. Tek bloklu deneysel tasarım kullanıldı ve her değerlendiriciye, su ile hazırlanmış beş Uluslararası Disfaji Diyet Standardizasyon Girişimi 2 kıvamındaki örnek rastgele sunuldu. Duyusal özellikler, 10 puanlık Sayısal değerlendirme ölçeği kullanılarak derecelendirildi. Koyulaştırılmış sıvıların akış özellikleri, hazırlandıktan 5 ila 180 dakika sonra IDDSI akış testi kullanılarak değerlendirildi. Bulgular: Çalışmaya 33 sağlıklı değerlendirici katıldı. Kıvam artırıcılar arasında tüm duyusal özellikler açısından anlamlı farklılıklar gözlendi (p<0.05) ve en iyi performansı Thicken Up Clear gösterdi. PraThick, kayganlık açısından Nutilis Powder’dan, yapışkanlık ve yutma kolaylığı açısından ise Nutilis Clear’dan üstün bulundu (p<0.05). Diğer parametrelerde ise PraThick, ithal ürünlerle benzer sonuçlar gösterdi (p>0.05). Akış özellikleri açısından, Nutilis Powder ile hazırlanan örnek hariç tüm koyulaştırılmış sıvılar 5-20 dakika arasında istenen Uluslararası Disfaji Diyet Standardizasyon Girişimi seviyelerine ulaştı ve zamanla hedef kıvamı korudu, buna karşın Nutilis Powder 20-60 dakika arasında kıvamda artış sergiledi. Sonuç: Bu çalışma, disfaji yönetiminde kullanılan kıvam artırıcıların duyusal özellikleri ve zamana bağlı akış özelliklerinin dikkate alınmasının önemini ortaya koymuş ve yerli ürün PraThick'in klinik olarak uygulanabilir, erişilebilir ve uygun maliyetli bir alternatif olarak kullanılabileceğini göstermiştir.

Keywords

yutma bozuklukları, IDDSI akış testi, duyusal değerlendirme, kıvam artırıcı, viskozite

Supporting Institution

Yok

Ethical Statement

Bu çalışmanın yürütülmesi için gerekli etik kurul onayı alınmıştır. Araştırma, Helsinki Bildirgesi ilkelerine uygun olarak yürütülmüştür. Çalışmaya katılan tüm gönüllülerden bilgilendirilmiş onam alınmıştır.

Thanks

Yazarlar duyusal teste katılan tüm katılımcılara teşekkürlerini sunarlar.

Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management

Abstract

Purpose: This study aimed to compare the sensory and flow properties of domestic and imported thickeners. Method: Five commercial thickeners (imported: Thicken Up Clear, Thicken Up Powder, Nutilis Clear, Nutilis Powder; domestic: PraThick) were tested. Sensory features—graininess, adhesiveness, slipperiness, ease of swallowing, and oral residue—were rated using a 10-point Visual Analog Scale. Thirty-three healthy assessors evaluated Dysphagia Diet Standardisation Initiative Level 2 samples prepared with water in a randomized design. Flow properties were analyzed with the IDDSI flow test at 5–180 minutes after preparation. Results: Significant differences were observed among thickeners across all sensory parameters (p<0.05). Thicken Up Clear achieved the best overall scores. PraThick showed greater slipperiness than Nutilis Powder and was superior to Nutilis Clear in adhesiveness and ease of swallowing (p<0.05). For other parameters, PraThick performed comparably to imported products (p>0.05). In flow tests, all thickeners except Nutilis Powder reached target Dysphagia Diet Standardisation Initiative Level levels within 5–20 minutes and maintained stability; Nutilis Powder exhibited progressive thickening from 20–60 minutes. Conclusion: Both sensory characteristics and time-dependent viscosity should be considered in dysphagia management. The domestic thickener PraThick demonstrated clinically acceptable, stable, and patient-preferred properties, offering a cost-effective alternative to imported products.

Keywords

deglutition disorders, IDDSI flow test, sensory evaluation, thickened liquids, viscosity

Supporting Institution

None

Ethical Statement

The necessary ethics committee approval was obtained for this study. The research was conducted in accordance with the principles of the Declaration of Helsinki. Informed consent was obtained from all volunteers who participated in the study.

Thanks

The authors thank to all participants who participated to sensory testing.

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Details

Primary Language

English

Subjects

Speech Pathology, Allied Health and Rehabilitation Science (Other)

Journal Section

Research Article

Authors

Ömer Faruk Yaşaroğlu
0000-0002-1867-9950
Türkiye

Ayşe Kübra Söyler ^*
0000-0002-0643-0517
Türkiye

Emre Cengiz
0000-0001-9224-6742
Türkiye

Şenay Demir Yazıcı
0000-0002-9375-2003
Türkiye

Publication Date

April 12, 2026

Submission Date

November 6, 2025

Acceptance Date

February 26, 2026

Published in Issue

Year 2026 Number: 1

DOI

https://doi.org/10.58563/dkyad-2026.93

IZ

https://izlik.org/JA42RS42WF

APA

Yaşaroğlu, Ö. F., Söyler, A. K., Cengiz, E., & Demir Yazıcı, Ş. (2026). Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management. Dil Konuşma Ve Yutma Araştırmaları Dergisi, 1, 53-75. https://doi.org/10.58563/dkyad-2026.93

AMA

1.Yaşaroğlu ÖF, Söyler AK, Cengiz E, Demir Yazıcı Ş. Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management. DKYAD. 2026;(1):53-75. doi:10.58563/dkyad-2026.93

Chicago

Yaşaroğlu, Ömer Faruk, Ayşe Kübra Söyler, Emre Cengiz, and Şenay Demir Yazıcı. 2026. “Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management”. Dil Konuşma Ve Yutma Araştırmaları Dergisi, no. 1: 53-75. https://doi.org/10.58563/dkyad-2026.93.

EndNote

Yaşaroğlu ÖF, Söyler AK, Cengiz E, Demir Yazıcı Ş (April 1, 2026) Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management. Dil Konuşma ve Yutma Araştırmaları Dergisi 1 53–75.

IEEE

[1]Ö. F. Yaşaroğlu, A. K. Söyler, E. Cengiz, and Ş. Demir Yazıcı, “Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management”, DKYAD, no. 1, pp. 53–75, Apr. 2026, doi: 10.58563/dkyad-2026.93.

ISNAD

Yaşaroğlu, Ömer Faruk - Söyler, Ayşe Kübra - Cengiz, Emre - Demir Yazıcı, Şenay. “Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management”. Dil Konuşma ve Yutma Araştırmaları Dergisi. 1 (April 1, 2026): 53-75. https://doi.org/10.58563/dkyad-2026.93.

JAMA

1.Yaşaroğlu ÖF, Söyler AK, Cengiz E, Demir Yazıcı Ş. Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management. DKYAD. 2026;:53–75.

MLA

Yaşaroğlu, Ömer Faruk, et al. “Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management”. Dil Konuşma Ve Yutma Araştırmaları Dergisi, no. 1, Apr. 2026, pp. 53-75, doi:10.58563/dkyad-2026.93.

Vancouver

1.Ömer Faruk Yaşaroğlu, Ayşe Kübra Söyler, Emre Cengiz, Şenay Demir Yazıcı. Evaluation of Sensory and Flow Properties of Domestic and Imported Thickeners Used in Dysphagia Management. DKYAD. 2026 Apr. 1;(1):53-75. doi:10.58563/dkyad-2026.93

Aim & Scope

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1. Crow (2010) defines the articulation competence as a skill where the inpidual correctly produces the speech sounds belonging to a specific language in a sequential and coherent manner.
2. Speech sound disorders include problems related to the erroneous production of speech sounds in terms of place, manner, speed, timing and pressure (Crow, 2010).
3. According to a study by Crow in 2010, the phonological competence refers to a skill in which the speech sounds are utilized appropriately in the language context.

Type of Citation	In case of the initial citation	Other citations to the same publication	The initial citation in the parenthesis format to the publication	Other citations to the same publication in the parenthesis format
Work by one author	Crow (2009)	Crow (2009)	(Crow, 2009)	(Crow, 2009)
Work by two authors	Crow and Stacey (2009)	Crow and Stacey (2009)	(Crow & Stacey, 2009)	(Crow & Stacey, 2009)
Work by three authors	Crow et al., (2009)	Crow et al., (2009)	(Crow et al., 2009)	(Crow et al., 2009)
Work by four authors	Crow et al., (2006)	Crow et al., (2006)	(Crow et al., 2006)	(Crow et al., 2006)
Work by five authors	Crow et al., (2006)	Crow et al., (2006)	(Crow et al., 2006)	(Crow et al., 2006)
Work by six authors (or more)	Crow et al., (2006)	Crow et al., (2006)	(Crow et al., 2006)	(Crow et al., 2006)
Name of the institution (abbreviated)	Association of Speech and Language Therapists (DKTD, 2006)	DKTD (2006)	(Association of Speech and Language Therapists [DKTD], 2006)	(DKTD, 2006)
Name of the institution (without abbreviation)	Anadolu University (2007)	Anadolu University (2007)	(Anadolu University, 2007)	(Anadolu University, 2007)

Tables and Figures

1. The title and number of the table should be above the table.
2. The title and number of the table and the text inside should be written in Times New Roman font, 10 font size, single-spaced, and left-aligned.
3. The initial letters in the table numbers should be capital, the table titles should be in italic and the initial letters should be capital.
4. Space should be provided both before the table title and after the table.
5. In the manuscript, a statement referring to the table such as “as shown in Table 1” should be made. The table should then follow.

6. The title and number of figures should be above the figure.
7. Each word in the title and number of figures should be capitalized and written in Times New Roman font, 10 font size, and left-aligned. The title should be in italic.
8. Space (enter) should be provided both before the figure title and following the figure.
9. In the manuscript, a statement referring to the figure such as “as shown in Figure 1” should be made. And the figure should follow.
10. If the figure is taken from a separate resource, a reference to the source should be given with the page number.

References
1. The references should be given in their alphabetical order. In case where the surnames are the same, the initial letters of the first names should be considered.
2. In the paragraph tab and indentation section, the right and left space should be zero, the custom tabs should be hanging and set to 1.25 cm (1 tab).
3. The references should be written with Times New Roman font, 10 font size, double-spaced and justified.
4. Some examples related to reporting the references are provided below. For further information, please see the “Publication Manual of American Psychological Association” (APA) (7th ed.).

Article	Vuolo, J., & Goffman, L. (2020). Vowel accuracy and segmental variability differentiate children with developmental language disorder in nonword repetition. Journal of Speech, Language, and Hearing Research, 63(12), 3897-4332. https://doi.org/10.104/2020_JSLHR-20-00166
Book	Bloodstein, O. & Bernstein Ratner, N. (2008). A Handbook on Stuttering. Delmar Learning.
Chapter in edited book	Rvachew, S. (2007). Perceptual foundations of speech acquisition. In S. McLeod (Ed.), The International Guide to Speech Acquisition (pp: 26-30). Delmar Learning.
Thesis	Ünal, Ö. (2011). Nasometric evaluation in resonans disorders: Turkish norms for 4-8 year-olds. Unpublished Doctoral dissertation. Anadolu University, Institute of Health Sciences, Eskişehir, Turkey
Internet Sources	Britton, L. (2021, Jan. 9). Why does the impact of COVID-19 feel so hard for many SLTs? RCSLT Home. https://www.rcslt.org/covid-case-studies/impact-of-covid-19-hard-for-many-slts/

Ethical Principles and Publication Policy

DKYAD Ethical Principles and Publication Policy

Journal of Language, Speech and Swallowing Research (DKYAD) is an open-access, double-blind, peer-reviewed academic journal that publishes articles about normal processes, disorders, assessment and remediation and other issues regarding the field of speech and language and swallowing. It is a publication of the Turkish Association of Speech and Language Therapists (DKTD). No fee is required by DKYAD for the processes of submission, reviewing, acceptance or publication of articles.

DKYAD is an open access journal and provides instant open access to its content. The Journal applies the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 (CC BY-NC-ND 4.0) license to its published articles. When authors submit their articles for publication, they agree to have the CC BY-NC-ND license applied to their work. Under this Open Access License, the authors agree that anyone may read, download, copy, print, distribute, or reuse the content of their articles free of charge for non-commercial purposes as long as the author and the original source are properly cited.

DKYAD aims to achieve high ethical standards in the publication of the articles. For this purpose, the journal adheres to the Code of Conduct and Best Practice Guidelines of COPE (Committee on Publication Ethics). The writers, chief editor, associate editors, reviewers and the journal management all share responsibility in achieving the declared goals. Editors are expected to follow the Cope Guidance for Editors and reviewers are expected to review the COPE Ethical Guidelines for Peer Reviewers and pay attention to the issues specified in the guidelines.

Within the scope of these guidelines:

Responsibilities of the Publisher and the Editors

• Editors have complete responsibility and authority to reject/accept an article.

• Only papers in line with the Journal’s scope of interest should be accepted.

• Editors should have no conflict of interest with respect to articles they reject/accept.

• Objectivity and anonymity should be maintained; information about the rejected articles, names of the reviewers and before publication any information regarding the accepted articles should not be revealed.

• Plagiarism and presentation of false data should be prevented.

Responsibilities of Authors

• Authors are expected to submit original articles.

• When authors submit their articles for publication, they agree to have the Creative Commons BY-NC-ND 4.0 license applied to their work. Under this Open Access License, the authors agree that anyone may read, download, copy, print, distribute, or reuse the content of their articles free of charge for non-commercial purposes as long as the author and the original source are properly cited.

• Authors should also confirm by signing a form entitled "Copyright and Publication Policy Consent Form" that (a) the article they submitted is their original work and has not been published or is under review in any other journal; (b) authors do not violate the copyright of the text, tables, and other documents pertaining to other individuals within the article; (c) authors accept and authorize DKYAD to permit the commercial use of the content as well as publication, republication in electronic and print format in the journal and distribution of the content, in addition to the non-exclusive rights DKYAD holds under the CC BY-NC-ND licence. In addition to these terms, the Authors should confirm that they retain all patent and other proprietary rights to the article, including copyright. Moreover, the Authors should assure in this form that they are responsible for any possible ethical violations, the results achieved and suggestions presented (See: DKYAD-Copyright and Publication Policy Consent Form).

• All individuals that have made a scientific and professional contribution to the study should be included as authors. The nature, content and percentage of the contribution should be revealed in detail (See: DKYAD Author Contribution Form).

• Direct or indirect institutional supports should be declared. Authors should be clear about any situations that might potentially create conflict of interest (See: DKYAD Conflict of Interest Disclosure Form).

• For all studies involving the ‘human factor’, confirmation is required by an ethics committee in accordance with the Helsinki Declaration (https://www.wma.net/policies-post/wma-declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects/).The authors have all the rights about the use of their data pertinent to their study. However, they should obtain ‘informed consent’ from their participants that contributed to the collection of data. Information regarding this procedure should be explained in detail under the Method section.

• The authors should provide complete and correct references to their sources. The manuscript is screened for plagiarism through softwares such as iThenticate or Turnitin and the maximum similarity rate is 20%. For more information, please see the Plagiarism Control Policy page.

• When necessary, authors should be ready to provide the raw data or output regarding the statistical analyses for purposes of transparency or clarity.

Responsibilities of Reviewers

• Reviewers act according to the requirements of the double-blind reviewing process.

• When sent an invitation for a review, they are expected to provide a prompt negative or positive response.

• If the topic is outside their area of expertise, they are expected to declare that and withdraw.

• The reviewers are expected to disclose any possible conflict of interest with the study. For example, if they are in the process of conducting a similar study, they should refrain from reviewing the article.

• When the reviewers detect any plagiarism, they are expected to inform the editor.

• The reviewers should be confidential about the information in the study they review before the study is published.

• The reviewers should inform the editors if they feel they are unable perform an objective and unbiased review.