https://doi.org/10.17113/ftb.63.03.25.9246

Supplement

Gluten Contamination of Rice: Analytical Testing vs. Consumer Perception – Is Rice Really Gluten Free?

Martina Bituh^1*, Mihaela Gulin², Ksenija Marković¹, Ines Panjkota Krbavčić¹ and Nada Vahčić¹

¹University of Zagreb Faculty of Food Technology and Biotechnology, Pierottijeva 6, 10000 Zagreb, Croatia

²Graduate student at University of Zagreb Faculty of Food Technology and Biotechnology, Pierottijeva 6, 10000 Zagreb, Croatia

Copyright © 2025 This is a Diamond Open Access article published under CC-BY licence. Copyright remains with the authors, who grant third parties the unrestricted right to use, copy, distribute and reproduce the article as long as the original author(s) and source are acknowledged.

Article history:

Received: 30 June 2025

Accepted: 15 September 2025

Published online: 24 September 2025

Keywords:

gluten-free diet; rice; consumer perception; ELISA; food safety, Croatian market

The content of this publication has not been approved by the United Nations and does not reflect the views of the United Nations or its officials or Member States.

Summary:

Research background. Gluten contamination is the main concern of those who follow a gluten-free diet. Although rice is naturally gluten-free, previous studies have identified gluten contamination of rice that can occur during processing, storage, handling or cooking. As a result, consumer confidence may be affected, emphasising the need to examine how these concerns shape their risk perceptions and influence their subsequent decisions. This study aims to evaluate: (i) the perceived risk of gluten contamination among gluten-free diet followers and (ii) the actual presence of gluten contamination in commercially available rice on the Croatian market.

Experimental approach. This cross-sectional study combined survey methods and laboratory analysis. An online questionnaire was used to assess the perceived risk of gluten contamination in rice among individuals following a gluten-free diet (N=66). The presence of gluten in forty-one samples of white, brown and parboiled rice from six producers on the Croatian market was then analysed using an enzyme-linked immunosorbent assay (ELISA).

Results and conclusions. Laboratory assays failed to detect gluten in any of the rice samples (limit of quantification 5 mg/kg), yet 54 (82 %) respondents expressed high uncertainty about the risk of gluten contamination in rice. These results show a significant discrepancy between consumer perception and scientific evidence. They emphasise the need for improved communication and clearer labelling to build consumer trust and support informed dietary choices.

Novelty and scientific contribution. This study highlights the gap between the perceived and actual risk of gluten contamination in naturally gluten-free food and emphasises the importance of addressing consumer concerns through better education and transparent product information.