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

Rapid Gluten Allergen Detection Using an Integrated Photoimaging Assay and Ionic Liquid Extraction Sensor

In recent years, food allergies and food sensitivities have remained critical public health problems that affect approximately 15% of the global population. Wheat is a major food source worldwide, but it is also a common food allergen. Celiac disease is chronic immune-mediated enteropathy triggered by exposure to dietary gluten in genetically predisposed individuals; it can be treated only through strict gluten avoidance. Therefore, rapid gluten detection is crucial for protecting the health of patients. Gluten contains two primary water-insoluble proteins: gliadin and glutenin. Gliadin is a key contributor to celiac disease and poses challenges for sample pretreatment owing to its insolubility, thereby reducing the accuracy and sensitivity of detection systems. Rapid sample processing is a critical problem in gliadin detection. In this report, we developed a gliadin sensor system called the integrated food allergy and microorganism sensor (iFAMs). The iFAMs comprises a gliadin lateral flow chip, a one-pot extraction solution, and an image assay app. The iFAMs enables gliadin extraction and detection in under 2 min with high sensitivity (0.04 mg/kg for gliadin, lower than the regulatory limit of 20 mg/kg). Users can easily measure gluten concentrations in samples and quantify gliadin levels using the smartphone-based image assay app. In samples collected from restaurants, the iFAMs successfully detected hidden gluten within "gluten-free" food items. The compact size and user-friendly design of the iFAMs render it suitable for not only consumers but also clinicians, food industries, and regulators to enhance food safety.

Risk of Gluten Cross-Contamination Due to Food Handling Practices: A Mini-Review

Celiac disease (CD) is an autoimmune disease triggered by the ingestion of gluten in genetically predisposed individuals, affecting 1.4% of the world population. CD induces an inflammatory reaction that compromises small intestine villi, leading to nutrient malabsorption, and gastro and extraintestinal manifestations. Although other treatment approaches are being studied, adherence to a gluten-free diet (GFD) is the only effective intervention to date. Despite this, about 50% of patients experience persistent inflammation, often associated with unintentional gluten ingestion through contaminated food. There are regulations for labeling gluten-free foods which specify a limit of 20 mg/kg (20 ppm). The risks of gluten cross-contamination above that level are present throughout the whole food production chain, emphasizing the need for caution. This review explores studies that tested different procedures regarding the shared production of gluten-containing and gluten-free food, including the use of shared equipment and utensils. A literature review covering PubMed, Scielo, Web of Science, VHL and Scopus identified five relevant studies. The results indicate that shared environments and equipment may not significantly increase gluten cross-contamination if appropriate protocols are followed. Simultaneous cooking of gluten-containing and gluten-free pizzas in shared ovens has demonstrated a low risk of contamination. In general, shared kitchen utensils and equipment (spoon, ladle, colander, knife, fryer, toaster) in controlled experiments did not lead to significant contamination of samples. On the other hand, cooking gluten-free and gluten-containing pasta in shared water resulted in gluten levels above the established limit of 20 ppm. However, rinsing the pasta under running water for a few seconds was enough to reduce the gluten content of the samples to less than 20 ppm.

Celiac Disease: Risks of Cross-Contamination and Strategies for Gluten Removal in Food Environments

Celiac disease (CD) is the chronic immune-mediated enteropathy of the small bowel, manifesting when exposure to gluten occurs in genetically predisposed individuals. Nowadays, the only treatment considered safe for CD is a gluten-free diet (GFD). However, one of the problems faced by celiac patients is the cross-contamination of gluten-free food when preparing meals, in addition to utensils, surfaces and equipment. This study aimed to evaluate cross-contamination in gluten-free products and strategies for removing gluten from cross-contamination in cooking environments. The selection of papers for this integrative review was carried out by searching different databases. Gluten cross-contamination is a global concern for celiac patients in food environments. Although some practices are positive, such as gluten labeling on processed food in several countries, it is crucial to promote good practices in food services around the world. Only a few studies showed effective results in removing gluten from surfaces and utensils; furthermore, sampling was limited, making it difficult to identify appropriate procedures to reduce cross-contamination. The variation in contamination in different kitchen environments also highlighted that celiac patients must continue paying attention to the methods used to prepare gluten-free food. More research is needed, especially into methods of removing gluten from surfaces and utensils, to ensure food safety for celiac patients in many food environments.

Commercial oats in gluten-free diet: A persistent risk for celiac patients

Background

Gluten-free diet is the treatment of celiac disease and other gluten-related disorders and excludes wheat, rye, and barley, while oats inclusion/exclusion has long been a matter of debate. A logo or catchphrase indicating the gluten-free condition in a product is all the consumer relies on to accept the product as suitable for his/her treatment. The oat-based gluten-free products represents a small market, which may have changed, and become more limited during COVID-19 pandemic.

Objective

To assess gluten contamination in all labeled oat-based gluten-free local and imported products available in the market, comparing them to matched regular gluten containing counterparts. As a secondary objective, unconventional flours available in the same sale points were also assessed.

Results

The search yielded 25 gluten-free labeled oat flours, rolled, and instant cereals, which were compared to 27 regular gluten containing equivalents. Gluten content was above the local (5 ppm) and the Codex Alimentarius cutoff (20 ppm) in 40 and 36% of the gluten-free labeled products, respectively. When all positive products were analyzed together, there were no differences in gluten content between labeled and unlabeled products. Locally produced products were more expensive, while rolled/instant oats were less contaminated than flours (p = 0.01). Precautionary labels advising presence of gluten as allergen was omitted in 37.0% of regular products. Only 33.3% of unconventional flours obtained from open markets and sold in bulk, were gluten contaminated.

Conclusion

Oat-based gluten-free products are currently highly contaminated. It is urgent to regulate them and implement protocols that allow safe consumption of these products.

Safety Assessment of Foods and Drinks Consumed by People on a Gluten-Free Diet

Naturally gluten-free foods and processed foods that do not contain information about the potential presence of gluten in them pose a hypothetical threat to people with food allergies and celiac disease. Patients who should follow a strict gluten-free diet do not always do so. Therefore, the aim of this research was to analyze certified “gluten-free” and naturally gluten-free products without labeled “may contain gluten” information in terms of their content of gluten proteins. The enzyme immunoassay AgraQuant Gluten G12 ELISA test kit was used for the analysis. Of all the products used in the research, only 5.8% were found to contain gluten above 20 ppm. Only one product labeled “gluten-free” was contaminated with gluten at 79.3 ppm (cider cake). In addition, our research also examined the gluten content of commercial beers containing barley malt not labeled as “gluten-free”. Research has shown that 60% of samples are not safe for those on a strict gluten-free diet. Our research clearly shows that many manufacturers, although they do not monitor their products for the presence of gluten in them, offer safe products, although they cannot be recommended in a gluten-free diet. Therefore, there is a strong need to increase the frequency of testing by food manufacturers for the presence of gluten in their products, so that the number of products approved for people on a gluten-free diet continues to increase.

Gluten contamination in labelled gluten-free, naturally gluten-free and meals in food services in low-, middle- and high-income countries: a systematic review and meta-analysis

The gluten-free diet is based on the consumption of foods without gluten, which aims to manage celiac disease. The concern of celiac patients is that these foods should be safe. However, gluten contamination can affect these foods. The objectives of this review and meta-analysis were first, to identify articles that detected gluten contamination in gluten-free foods using validated methods. Second, to quantify the overall prevalence of gluten contamination of naturally gluten-free foods, labelled gluten-free products, and meals prepared in food services. Third, to highlight the influence of the country's income and the period of study on this prevalence. The studies were identified in Scopus, Science Direct, Web of Science, PubMed, and Google Scholar. Forty articles were included according to PRISMA guidelines. The statistical meta-analysis was performed using MedCalc 19 software. The results show that in the gluten-free foods analysed, the overall prevalence of gluten contamination was estimated at 15.12% (95% CI: 9.56%-21.70%), with more than 20 mg/kg of gluten. Naturally gluten-free foods were significantly more contaminated than labelled gluten-free products and than meals in food services (28.32%; 9.52%; 4.66% respectively; p < 0.001). Moreover, it was noticed that oats were the most contaminated food. In addition, the prevalence of gluten contamination has significantly decreased over time. The majority of the studies were carried out in upper-middle-income and high-income countries, while only one study was conducted in lower-middle income countries. Therefore, it is necessary to implement preventive actions to reduce gluten contamination, ensuring safe gluten-free foods for celiac patients, including low-income countries.

Food Safety and Cross-Contamination of Gluten-Free Products: A Narrative Review

A gluten-free diet (GFD) is currently the only effective treatment for celiac disease (CD); an individual’s daily intake of gluten should not exceed 10 mg. However, it is difficult to maintain a strict oral diet for life and at least one-third of patients with CD are exposed to gluten, despite their best efforts at dietary modifications. It has been demonstrated that both natural and certified gluten-free foods can be heavily contaminated with gluten well above the commonly accepted threshold of 20 mg/kg. Moreover, meals from food services such as restaurants, workplaces, and schools remain a significant risk for inadvertent gluten exposure. Other possible sources of gluten are non-certified oat products, numerous composite foods, medications, and cosmetics that unexpectedly contain “hidden” vital gluten, a proteinaceous by-product of wheat starch production. A number of immunochemical assays are commercially available worldwide to detect gluten. Each method has specific features, such as format, sample extraction buffers, extraction time and temperature, characteristics of the antibodies, recognition epitope, and the reference material used for calibration. Due to these differences and a lack of official reference material, the results of gluten quantitation may deviate systematically. In conclusion, incorrect gluten quantitation, improper product labeling, and poor consumer awareness, which results in the inadvertent intake of relatively high amounts of gluten, can be factors that compromise the health of patients with CD.

Gluten-Free Labeling Is Misused Frequently in Foods Marketed in Northwestern Mexico

Background: Patients with celiac disease (CD) require a gluten-free (GF) diet, including industrialized products containing ≤ 20 mg gluten/kg. The market status of GF food products is almost unknown in Mexico. Therefore, we studied the GF-labeled products on the northwestern Mexican market and analyzed their gluten content. Methods: We searched for GF type of foods in three different supermarkets of each chain in Mexicali Baja California and Hermosillo Sonora and corroborated the price, origin, and GF certification of each item using internet sites. We quantified the gluten in the foods using the sandwich R5-enzyme-linked immunosorbent assay (ELISA) and detected their immune-reactivity for IgA from patients with CD. Results: The study included >263 different GF-labeled foodstuffs, and 55% of them were made in Mexico. The Mexican items were principally flours, sausages, bread and bakery, milk-type products, and tortillas, while pasta, snacks, and breakfast cereals were mainly imported. The cost ratio of GF products to the conventional mean was 3.5, ranging principally from 1 to 13. The most common GF-labeled foods were flours and pasta (34), cookies and snacks (32), breakfast cereals, sausages, and milk-type products (18-20). Although 36% of the products were certified, 17.4% of the analyzed samples contained >20 mg gluten/kg, mainly the non-certified ones and those made in Mexico. IgA from patients with CD reacted in vitro against gluten proteins from the contaminated GF-labeled products. Conclusion: The accessibility of GF products in the northwestern Mexican market is wide; however, such products are expensive, and some could be risky for patients with CD because they contain gluten, which is recognized by the immune systems of these patients.

Medical nutrition therapy of pediatric type 1 diabetes mellitus in India: Unique aspects and challenges

Medical nutrition therapy (MNT) is a vital aspect of management of type 1 diabetes mellitus (T1DM) and should be tailored to ethnic and family traditions and the socioeconomic and educational status of the patient. In this article, we discuss the unique aspects of MNT in children and adolescents with T1DM in the Indian setting, with focus on the challenges faced by patients, dieticians and physicians and how these can be overcome. The authors reviewed the available literature on MNT in T1DM from India and prepared the document based on their vast collective clinical experience in treating patients with T1DM from different regions in India. Indian diets are predominantly carbohydrate-based with high glycemic index (GI) and low protein content. Various methods are available to increase the protein and fiber content and reduce the GI of food in order to limit glycemic excursions. Insulin regimens need to be tailored to the child's school timings, meal schedule, and the availability of a responsible adult to supervise/administer insulin. All patients, irrespective of economic and education background, should be taught the broad principles of healthy eating, balanced diet and carbohydrate counting. There are various barriers to dietary compliance, including joint family system, changing lifestyles, and other factors which need to be addressed. There is a need to customize dietary management according to patient characteristics and needs and develop standardized patient educational material on principles of healthy eating in various regional languages.

Gluten content in labeled and unlabeled gluten-free food products used by patients with celiac disease

OBJECTIVE

Gluten-free (GF) diet is the only reliable treatment for patients with celiac disease (CeD), but data on the extent of gluten contamination in GF food available in India is scanty. We evaluated gluten content in labeled, imported, and non-labeled GF food products currently available in the Indian market.

METHODS

Overall, 794 processed and commercially available packaged GF products (labeled GF (n = 360), imported GF (n = 80), and non-labeled/naturally GF (n = 354)) were collected from supermarkets of National Capital Region of India. Those unavailable in stores were purchased from e-commerce sites or directly from the manufacturers. Gluten level in them was determined by Ridascreen Gliadin sandwich R5 enzyme-linked immunosorbent assay (R-Biopharm AG, Germany). As per Codex Alimentarius and Food Safety and Standard Authority of India, "gluten free" labeled products must not contain > 20 mg/kg of gluten.

RESULTS

Overall, 10.1% of 794 GF products including 38 (10.8%) of 360 labeled and 42 (11.8%) of 354 non-labeled/naturally GF food products had gluten content > 20 mg/kg (range: 24.43-355 and 23.2-463.8 mg/kg, respectively). None of the imported GF products had gluten more than the recommended limits. Contaminated products most commonly belonged to cereal and their products (flours, coarse grains, pasta/macaroni, snack foods) pulse flours, spices, and bakery items.

CONCLUSIONS

A substantial proportion (10.1%) of GF food products (both labeled and non-labeled) available in India have gluten content greater than the prescribed limits of <20 mg/kg. Physicians, dietitians, support group, and patients with CeD should be made aware of this fact and regulatory bodies should ensure quality assurance.

Quantification of Accidental Gluten Contamination in the Diet of Children with Treated Celiac Disease

A strict gluten-free diet is extremely difficult to maintain. Protracted ingestion of gluten traces (>10 mg/day) is sufficient to cause significant damage in the architecture of the small intestinal mucosa in patients on treatment for celiac disease. The aim of this study was to directly measure the level of contaminating gluten in the daily diet of celiac children following a gluten-free diet. From April 2019 to December 2019, celiac disease children (2-18 years old) on a gluten-free diet for ≥6 months were offered to participate in this prospective-observational study. Patients and their caregivers were invited to provide a representative portion (about 10 g) of all meals consumed during a 24-h period. Participants were requested to weigh all ingested food and report items in a 24-h food diary. The gluten content was quantified by the R5 sandwich enzyme-linked immunosorbent assay method. Sixty-nine children completed the protocol. Overall, 12/448 (2.7%) food samples contained detectable amounts of gluten; of them, 11 contained 5-20 ppm and 1 >20 ppm. The 12 contaminated food samples belonged to 5/69 enrolled patients. In these 5 children, the daily gluten intake was well below the safety threshold of 10 mg/day. The present findings suggest that in a country characterized by high celiac disease awareness, the daily unintended exposure to gluten of treated celiac children on regular follow-up is very low; reassuringly, the presence of gluten traces did not lead to exceed the tolerable threshold of 10 mg/day of gluten intake in the gluten-free diet.

Potential ways for gluten contamination of gluten-free grain and gluten-free foods: the buckwheat case

Buckwheat has been reported to be responsible for gluten contamination in manufactured gluten-free foods (mGFFs) although it is inherently gluten-free (GF). It could happen through buckwheat grains contacting gluten-containing (GC) grains and surfaces contacted by GC grains during pre-manufacturing practices. To simulate grain contact, whole and broken GC grains (wheat, rye, barley, and oat) were mixed into buckwheat grains at the ratio of 2.5-10.0%. Grains were agitated in vessels with inner surfaces covered with buckwheat grain. Gluten was not detected in buckwheat grains contacting whole GC grains at all mixing ratios. It was not detected in the case of broken GC grains at the mixing ratio of 2.5% and oat grains at all mixing ratios. Gluten concentration increased with the increasing mixing ratio and the natural gluten concentration of broken GC grains. To simulate surface contact, GC grains were first agitated in galvanised steel vessels and then buckwheat grains were agitated together under the same conditions. Gluten was detected on galvanised steel surfaces contacted by whole and broken GC grains. It was not detected in buckwheat grains contacting the surfaces contaminated by whole GC grains. Gluten was detected in buckwheat grain in the case of the broken GC grains except for oats. Gluten concentrations increased with increasing natural gluten concentration of GC grains. Contamination of mGFFs could be linked to potential contact with buckwheat grain. This contamination issue could be resolved through regulations mandating the proof of being GF for ingredients used in the production of mGFFs.