Gluten contamination in labelled and naturally gluten-free grain products in southern India

ABSTRACT

Consumption of a gluten-free diet or avoiding exposure to gluten is the only feasible and effective treatment available for coeliac patients to date. Although many grains and their products are naturally gluten-free, the possibility of gluten cross-contamination must be considered. Since such data are not available for Indian markets, we carried out this pilot study (n = 160) to assess gluten contamination in various grain-based food products from the category of breakfast products, flours, and batters made from grain that are naturally gluten free. The gluten was extracted from samples using 60% ethanol and gluten analysis was carried out using a commercially available competitive ELISA, which utilises a monoclonal antibody. Nearly 9.8% of the products labelled as gluten-free and 36.7% of the products made from naturally gluten-free grain were found to contain gluten above 20 mg/kg. Among products made from naturally gluten-free grain, 35.9% of the flour samples and 85% of the oat samples (11.67–1830 mg/kg) were contaminated with gluten. In the case of flours, unbranded samples collected from local markets (70%) and directly from local mills (30%) showed gluten content above Codex safety levels (20–400 mg/kg). Among products labelled as gluten free (n = 51), only 5 samples showed gluten contamination above 20 mg/kg although levels were well within 100 mg/kg (32.5 ± 5.8). Our study suggests that there is a likelihood of gluten contamination in products that are sourced from local retailers and millers.

KEYWORDS:

• Gluten free
• coeliac disease
• ELISA
• oats
• milling flour
• cereals

Acknowledgments

The authors wish to thank the Director, National Institute of Nutrition, ICMR for her support to the study.

Disclosure statement

No potential conflict of interest was reported by the authors.