A Review on the Gluten-Free Diet: Technological and Nutritional Challenges

Optimizing production of gluten-free, sugar-reduced cupcakes: Utilizing stevia as natural sweetener and psyllium as gluten substitute

A comprehensive study was conducted to assess the effects of stevia (0%-1.2%), psyllium (0%-4%), and baking method (airfryer and oven) on the physical, textural, sensory, and pore characteristics of gluten-free, sugar-reduced cupcakes. The formulation was optimized using Response Surface Methodology-Central Composite Face-Centered Design (CCFD). Based on numerical optimization, the best cupcake formulation was predicted to contain 0.68% stevia and 1.82% psyllium, using the oven baking method. The optimized cupcake produced at this formulation exhibited the following characteristics: specific volume 38.75 mL/g, hardness 1710.85 gf, springiness 0.950, cohesiveness 0.638, gumminess 1119, chewiness 1042, resilience 0.350, and 44 pores. To analyze pore characteristics, the Otsu thresholding algorithm was employed, revealing a 2.5-fold increase in the number of pores in the optimized cupcake compared to the control. This study demonstrates that the combination of stevia as natural sweetener and psyllium as gluten substitute significantly enhances the quality of a low-calorie, gluten-free cupcake. Furthermore, this formulation provides a promising, clean option for consumers with chronic diseases such as celiac and diabetes.

Variations in the composition and frequency of celiac disease epitopes among synthetic wheat lines

Bread wheat serves as an important staple crop in the human diet, largely because of the physicochemical properties of its dough and its protein content. Gluten is the main and complex component of wheat proteins. Despite the significant importance in breadmaking properties, wheat gluten contains some immunogenic peptides capable of triggering a T cell reaction in celiac disease (CD) patients, leading to inflammation in the small intestine. Among gluten proteins, α-gliadins are the most immunogenic components because they possess the primary T-cell stimulating epitopes (DQ2.5-Glia-α1, DQ2.5-Glia-α2, and DQ2.5-Glia-α3), which are primarily located on the D subgenome. Developing new wheat varieties by integrating the D subgenome from various sources is not only useful for introducing low immunogenic gluten, but it can also circumvent the challenging policies arising from the manipulation of wheat genome through transgenic approaches. Here, we performed RNA amplicon sequencing of the most toxic region of alpha-gliadins to analyze the content and composition of CD-related alpha-gliadin epitopes across eight synthetic wheat lines developed from crosses between durum wheat and different Aegilops species containing the D-genome (Ae. tauschii, Ae. crassa, and Ae. ventricosa). By searching the previously identified 121 epitopes and those with one mismatch in our amplicons, we found 54 different α-gliadins epitopes across our genotypes, four of which were new variants. The canonical epitopes were present in all lines, although their expression patterns varied. The occurrence of DQ2.5-Glia-α1a and DQ2.5-Glia-α3 was higher than that of DQ2.5-Glia-α2 and DQ2.5-Glia-α1b across all genotypes. Since a higher quantity of toxic alpha-gliadin epitopes is associated with increased immunogenicity in individuals susceptible to celiac disease, we measured the frequency of the most toxic alpha-gliadin epitopes among different synthetic lines to estimate the overall immunogenic load of our lines. Generally, the immunogenic load of lines with the D-genome originating from Ae. crassa was much lower than those with the D-genome from Ae. tauschii. In this way, the Ae. tauschii derived lines 5 and 6 contained higher levels of toxic alpha-gliadin epitopes, while lines 3, 4, and 7 (derived from Ae. crassa) contained the lowest levels of toxic peptides. We conclude that replacing the bread wheat D-genome with that of the Ae. crassa may help lower the gluten immunogenicity in the deriving synthetic wheat lines.

Celiac Disease: Beyond Diet and Food Awareness

Celiac disease is attributable to a combination of genetic predisposition and exposure to dietary gluten, with immune system involvement. The incidence is increasing globally, and the societal economic burden of celiac disease stretches beyond the cost of gluten-free food. This enteropathy that affects the small intestine has been related to different disorders and comorbidities. Thus, the implications of suffering from this disease are multidimensional and need further consideration. Celiac disease is a serious condition that remains under-recognized, resulting in an increased need for programs for better management. This review aims to summarize the current evidence regarding celiac diseases, with special emphasis on clinical implications, diagnosis, dietary management, socioeconomical aspects, and future perspectives.

Dietary Challenges in Children with Gluten-Related Disorders: A Study on Food Neophobia

BACKGROUND/OBJECTIVES

Food neophobia (FN) in childhood is characterized by resistance to new foods, potentially impairing health and diet quality and impacting physical and mental development. Adequate nutrition in early childhood is crucial to preventing future problems. FN demands special attention, especially in cases of gluten-related disorders (GRD), due to the risks associated with restrictive diets and food allergies. The objective of this study was to investigate and classify the prevalence of FN among Brazilian children aged 4 to 11 years with GRD.

METHODS

For this cross-sectional study, a questionnaire validated in Portuguese, with 25 items, assessed FN in three domains: general FN, FN of fruits, and FN of vegetables. Data were collected via Google Forms.

RESULTS

Of 209 children with GRD, the majority were female, 83.7% were diagnosed with celiac conditions, 81.3% followed a diet, and 43.1% had moderate total food neophobia. Brazilian children with GRD have a moderate prevalence of food neophobia. General and vegetable neophobia predominate, while fruit FN is lower. Girls exhibit greater neophobia towards vegetables.

CONCLUSIONS

Neophobia does not vary with age, suggesting the persistence of the behavior and potential nutritional challenges in adult life. Differentiated attention to this population is essential to minimize long-term impacts.

Exploring Demand: Challenges and Opportunities for Free-From and Organic Foods in Portuguese Market

The rising prevalence of food intolerances and increased health and environmental consciousness has driven the demand for free-from (FF) and organic products. This study aims to analyze consumer needs, motivations, and challenges related to these products in Portugal through an online survey with 2268 eligible responses, with a median age of the participants of 41 years. The sample was predominantly female (76.9%), with male participants comprising 23.1% of the sample. The results show that 97.4% of the respondents were aware of FF products, with 60.0% being regular consumers, particularly of lactose-free milk and gluten-free bread and biscuits. Significant market gaps were identified in the variety of FF bread (62.8%), pastries (49.0%), and cookies (38.4%). The consumers identified high prices (84.9%) and excessive sugar/fat content (52.1%) as the main drawbacks of FF products currently on the market. The women showed greater knowledge and purchase levels compared to the men. The trust in organic certification was low (21.4%), with skepticism higher among the lower-income and male participants. Despite this, 78.1% believed in the health benefits of organic products, and 72.2% agreed that increased demand could lower prices. Overall, this study highlights the need for greater product variety, improved transparency, and consumer education to enhance market trust and accessibility.

Impact of low FODMAP sourdough bread on gut microbiota using an in vitro colonic fermentation model

This study explores the development of whole-grain sourdough bread with reduced FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) content to offer dietary solutions for individuals with irritable bowel syndrome (IBS). Three sourdough breads were prepared using different lactic acid bacteria (LAB) strains including Lactiplantibacillus plantarum FST1.7 (SD-FST1.7), Lacticaseibacillus paracasei R3 (SD-R3), and Pediococcus pentosaceus RYE106 (SD-RYE106). A control sourdough bread was prepared using baker's yeast (SD-control). In vitro digestion and in vitro colonic fermentation were employed on bread samples with cellulose (negative control) and inulin (positive control), followed by 16S rRNA sequencing and short-chain fatty acid (SCFA) analysis to evaluate the impact on gut microbiota and SCFA levels. Alpha and beta diversity did not reveal any significant differences within the groups following in vitro colonic fermentation (FDR > 0.05). Taxonomic analysis displayed Firmicutes as the predominant phylum across all fecal samples at the end of colonic fermentation. Actinobacteriota was significantly lower in cellulose fermented fecal samples compared to samples fermented with SD-Control (ANCOMBC, FDR = 0.02) and inulin (ANCOMBC, FDR = 0.0001). Fecal samples fermented with inulin had significantly higher Bacteroidota levels compared to those fermented with cellulose (ANCOMBC, FDR =0.002). Acetate levels were higher in fecal samples fermented with SD-FST1.7 compared to those fermented with SD-R3 and SD-RYE106 (p = 0.03 for both). Positive correlations between butyrate and Lachnospira, Agathobacter, and Bifidobacterium were observed, demonstrating the potential of sourdough fermentation to influence gut health and support IBS management.

Brassica oleracea var italica and Their By-Products as Source of Bioactive Compounds and Food Applications in Bakery Products

Broccoli (Brassica oleracea var. italica) is one of the most consumed cruciferous crops in the world, with China and Spain acting as the main producers from outside and within the EU, respectively. Broccoli florets are edible, while the leaves and stalks, discarded in the field and during processing, are by-products. Therefore, the objective of this study was to conduct a comprehensive review of the nutrient and phytochemical composition of broccoli and its by-products, as well as its beneficial effects. In addition, the study highlights the revalorization of broccoli by-products through innovative green technologies and explores their potential use in bakery products for the development of functional foods. The studies suggested that broccoli is characterized by a high content of nutrients and bioactive compounds, including vitamins, fiber, glucosinolates, and phenolic compounds, and their content varied with various parts. This high content of value-added compounds gives broccoli and its various parts beneficial properties, including anti-cancer, anti-inflammatory, antioxidant, antimicrobial, metabolic disorder regulatory, and neuroprotective effects. Furthermore, broccoli and its by-products can play a key role in food applications by improving the nutritional profile of products due to their rich content of bioactive compounds. As a result, it is essential to harness the potential of the broccoli and its by-products that are generated during its processing through an appropriate agro-industrial revalorization, using environmentally friendly techniques.

Technological quality improvement of gluten-free dough and chapatti-making by incorporation of modified oat 1,4-β-D-glucan

The present study aimed to explore the contribution of untreated (UtβG) and modified oat 1,4-β-D-glucan (OzβG) to the quality of gluten-free chapattis at varying concentrations (0, 1.5, 3, and 4.5 % labelled as M0, M1, M2 and M3 for maize chapattis and F0, F1, F2 and F3 for finger millet chapattis, respectively). The functionality of flours was significantly enhanced by the addition of UtβG and OzβG. However, OzβG incorporated flour exhibited a more pronounced influence on both functional and farinographic parameters when compared to flours with UtβG. Further, the hardness of the chapattis decreased with incorporation of OzβG and it was lowest for M2 and F2 i.e. 6.38 N and 5.27 N, respectively due to the formation of more carboxyl and hydroxyl groups, which had more affinity towards water molecules. The sensory analysis indicated that OzβG incorporated M2 and F2chapattis exhibited the highest overall acceptability. Hence, this study provides valuable insights into the utilization of UtβG and OzβG for the formulation of gluten-free chapattis with better dough characteristics and chapatti-making properties.

Gluten Unraveled: Latest Insights on Terminology, Diagnosis, Pathophysiology, Dietary Strategies, and Intestinal Microbiota Modulations-A Decade in Review

A decade of research on gluten-related disorders (GRDs) is reviewed in this study, with a particular emphasis on celiac disease (CD) and non-celiac gluten sensitivity (NCGS). GRDs are triggered by the ingestion of gluten and gluten-like proteins found in wheat, barley, and rye. These proteins lead to intestinal damage in celiac disease, an autoimmune condition characterized by villous atrophy and a variety of gastrointestinal and extraintestinal symptoms. More enigmatic and less understood, NCGS involves symptoms similar to CD but without the immunological reaction or intestinal damage. Recent years have seen advances in the understanding of GRDs, particularly in connection to how intestinal microbiota influences disease progression and patient outcomes. The gluten-free diet (GFD) is still the standard therapy recommended for GRDs despite significant challenges, as discussed in this article. Precise diagnostic methods, patient education and dietary counseling are critical for improving patients' quality of life. The purpose of this review is to provide a more clear and up-to-date understanding of GRDs, and to help further research on this important topic.

Nutritional, antioxidant and biological activity characterization of orange peel flour to produce nutraceutical gluten-free muffins

Celiac disease - a prevalent food intolerance - requires strict adherence to a lifelong gluten-free (GF) diet as the only effective treatment. However, GF products often lack soluble fibre and have a high glycaemic index. Consequently, there is a pressing need in the food industry to develop GF products with improved nutritional profiles. In this context, the impact of incorporating orange peel flour (OPF) into muffins undergoing sourdough fermentation was examined, focusing on their technological, antioxidant, and nutritional characteristics. The functional properties of OPF were investigated using human colon carcinoma HCT8 cells as a model system. Treatment with OPF extract demonstrated a notable reduction in malignant cell viability and intracellular ROS levels, indicating potent antioxidant capabilities. Western blot analysis revealed significant alterations in key signalling pathways, including increased phosphorylation of NF-kB at serine 536 and reduced intracellular levels of caspase-3, alongside increased phosphorylation of RIPK3 and MLKL, suggesting potential involvement in necroptosis. OPF incorporation in muffins with sourdough increased antioxidant activity, reduced glycaemic index, and affected the volatile profile. Furthermore, based on simulated colonic fermentation, muffins with OPF showed a slight prebiotic effect, supported by the significant increase in bacillus-shaped lactic acid bacteria and Clostridia population. Overall, OPF-enriched muffins demonstrated considerable antioxidant effects and impacts on cell viability, underscoring their potential as functional ingredients in GF products. These findings signify the prospect of OPF enhancing the nutritional profiles and conferring health benefits of GF muffins.

Effect of starch degradation induced by extruded pregelatinization treatment on the quality of gluten-free brown rice bread

There is considerable interest in preparing high-quality gluten-free bread. The effect of the molecular structure of extruded pregelatinization starch on the dough's rheological properties and the brown rice bread's quality was investigated. Extruded rice starch (ERS) was prepared with various added moisture contents of 20 % (ERS20), 30 % (ERS30), and 40 % (ERS40), respectively. ERS had smaller molecular weight and more short branched chains as the moisture content decreased. The dough elasticity and deformation resistance were improved with the ERS supplementation and in the order of ERS40 > ERS30 > ERS20 at the same level. Fortification with ERS improved the gluten-free brown rice bread quality. Compared to the control group, breadcrumbs supplemented with ERS20 at the 10 % level showed an increase in cell density from 17.87 cm-2 to 28.32 cm-2, a decrease in mean cell size from 1.22 mm2 to 0.81 mm2, and no significant change in cell area fraction. In addition, the specific volume increased from 1.50 cm3/g to 2.04 cm3/g, the hardness decreased from 14.34 N to 6.28 N, and the springiness increased from 0.56 to 0.74. The addition of extruded pregelatinization starches with smaller molecular weights and higher proportions of short chains is promising for preparing high-quality gluten-free bread.

A Narrative Review of the Significance of Popular Diets in Diabetes Mellitus Management

Diabetes mellitus is a collection of metabolic disorders marked by elevated levels of glucose in the blood due to irregularities in the generation or functioning of insulin. Medical nutrition therapy and weight loss are crucial elements in the management of diabetes and the prevention of complications. Several diets have become popular over time for the goal of achieving weight loss, but their popularity has declined due to a lack of reliable scientific evidence. This study classifies popular diets into three categories: diets that manage the composition of macronutrients, diets that restrict specific foods or food groups, and diets that manipulate meal timing. The review includes research studies that investigated the effects of popular diets on the prevention, management, and complications of diabetes. It is clear that different popular diets can have positive effects on both preventing and treating diabetes and preventing and treating complications related to diabetes. However, it is not practical to determine which diet is the most effective option for preventing or controlling diabetes. Thus, the main focus should be on common underlying factors that support well-being, such as decreasing the intake of refined grains and added sugar, choosing non-starchy vegetables, and giving priority to whole foods over processed foods whenever possible, until there is stronger evidence supporting the specific benefits of different dietary patterns.

Gluten-Free Diet and Other Celiac Disease Therapies: Current Understanding and Emerging Strategies

A lifelong gluten-free diet (GFD) is the only treatment for celiac disease and other gluten-related disorders. Nevertheless, strict adherence to the GFD is often challenging due to concerns about social isolation, risk of gluten contaminations, high cost, poor quality and the taste of gluten-free products. Moreover, although the GFD is effective in achieving mucosal healing, it may lead to dietary imbalances due to nutrient deficiencies over a long period of time. To overcome these issues, several gluten-free wheat flours have been developed to create products that closely resemble their gluten-containing counterparts. Furthermore, given the critical importance of adhering to the GFD, it becomes essential to promote adherence and monitor possible voluntary or involuntary transgressions. Various methods, including clinical assessment, questionnaires, serology for celiac disease, duodenal biopsies and the detection of Gluten Immunogenic Peptides (GIPs) are employed for this purpose, but none are considered entirely satisfactory. Since adherence to the GFD poses challenges, alternative therapies should be implemented in the coming years to improve treatment efficacy and the quality of life of patients with celiac disease. The aim of this narrative review is to explore current knowledge of the GFD and investigate its future perspectives, focusing on technology advancements, follow-up strategies and insights into a rapidly changing future.

Effects of transamidation vs. fermentation to reduce the gluten content of the Triticum monococcum wheat cultivar Hammurabi: analysis of biochemical, baking and sensory parameters

The Triticum monococcum cultivar Hammurabi has been considered a wheat with reduced gluten toxicity for intolerant people. To further reduce gluten toxicity, we tested two biotechnological treatments on Hammurabi flour, fermentation by endogenous microbiota and transamidation by microbial transglutaminase. After 1 day of fermentation, the detectable gluten content dropped to 51.4% ± 6.4% (R5‐ELISA). Interestingly, microbial hydrolysis did not change the content of the water‐insoluble gliadin fraction. Transamidation of Hammurabi caused a greater reduction of the native gluten to 33.5% ± 3.3% (P < 0.01) and changed its physical properties, as it became water soluble. Interestingly, only dough from transamidated Hammurabi flour could leaven, similarly to the untreated dough, while in fermented Hammurabi dough, the rising activity of the added yeast was inhibited. Baking analysis indicated no substantial difference between transamidated and untreated Hammurabi breads. Descriptive sensory analysis showed that darkness appearance parameters and texture parameters were significantly altered in transamidated bread. Importantly, the treatment did not influence wheaty flavour or cereal odour, two mainly expected organoleptic features. Our data may have important implications in the perspective of manufacturing innovative foods for people predisposed to or suffering from gluten intolerance.

The association of gluten-free diet with thyroid autoimmunity in patients with celiac disease: a meta-analysis

Background: Thyroid autoimmunity is an immune response to thyroid antigens that causes varying degrees of thyroid dysfunction. The sole effective treatment for Celiac Disease (CD) is a gluten-free diet (GFD). However, the association between GFD and thyroid autoimmunity in patients with CD has not been confirmed. Methods: A comprehensive search of several databases, involving PubMed, Embase, Web of Science, Medline, and Cochrane databases, was conducted to identify studies that primarily addressed the effects of GFD on thyroid autoimmunity in CD subjects. The meta-analysis involved studies that compared the risk of ATPO and ATG antibody positivity in CD patients with GFD, the risk of developing AITD, and the risk of developing thyroid dysfunction. Fixed-effects models or random-effects models were used to calculate the odds ratios (ORs) and their 95% confidence intervals (95% CIs). Results: A total of 10 observational studies met the inclusion criteria and included 6423 subjects. The results indicated that GFD is positively associated with thyroid autoimmunity in the children subgroup of CD patients (OR = 1.61, 95%CI 1.06-2.43, P = 0.02). However, there was no significant difference in thyroid autoimmunity between the group adhering to GFD and the control group in the total CD population. Conclusion: The results seem to indicate that subjects with a more pronounced autoimmunity (such as to have an early onset of CD) appear to have a greater risk of thyroid autoimmunity.

Evaluation of the effect of gluten-free diet and Mediterranean diet on autoimmune system in patients with Hashimoto's thyroiditis

Hashimoto's thyroiditis is an autoimmune disease in which thyroid cells are attacked through cell-and antibody-mediated immune processes. A gluten-free diet reduces antibody concentration and regulates thyroid autoimmunization. Mediterranean diet reduces oxidative stress. This study evaluates the short-term effects of Mediterranean, gluten-free, and Mediterranean gluten-free dietary patterns on thyroid function and autoantibody levels of patients. The 40 patients with Hashimoto's thyroiditis included in the study were randomly divided into four groups (defined as gluten-free, Mediterranean, Mediterranean gluten-free, and controls) for 12 weeks. Thyroid function tests, autoantibody levels, and food consumption were recorded at the beginning and end of the study. There was no statistically significant difference in TSH levels of the groups before the intervention, but a statistically significant difference was found afterward (p < 0.05). Free T3 hormone levels showed a statistically significant difference across the groups before and after the intervention (p < 0.05). Free T3 hormone levels increased significantly in all intervention groups after the intervention, with the highest increase in the Mediterranean group (p < 0.05). In the intervention groups, anti-TPO and anti-Tg levels decreased after the intervention; however, this difference was not significant across groups (p > 0.05). In addition, body weight, body mass index, waist and hip circumference averages decreased significantly in all intervention groups compared with controls (p < 0.05). The study achieved an increase in Free T3 hormone levels in the intervention groups. The most marked difference was seen in the Mediterranean gluten-free diet model, which may be due to the anti-inflammatory effect of both Mediterranean and gluten-free diets and the loss of body weight as a result of the intervention.

Plant-Based Antioxidants in Gluten-Free Bread Production: Sources, Technological and Sensory Aspects, Enhancing Strategies and Constraints

The recognized contribution of antioxidant compounds to overall health maintenance and spotted deficiencies in celiac patients' diets has driven more intensive research regarding antioxidant compounds' inclusion in gluten-free bread (GFB) production during the last decade. The presented review gathered information that provided insights into plant-based antioxidant sources which are applicable in GFB production through the resulting changes in the technological, sensory, and nutritional quality of the resulting antioxidant-enriched GFB. The influence of the bread-making process on the antioxidant compounds' content alteration and applied methods for their quantification in GFB matrices were also discussed, together with strategies for enhancing the antioxidant compounds' content, their bioaccessibility, and their bioavailability, highlighting the existing contradictions and constraints. The addition of plant-based antioxidant compounds generally improved the antioxidant content and activity of GFB, without a profound detrimental effect on its technological quality and sensory acceptability, and with the extent of the improvement being dependent on the source richness and the amount added. The determination of a pertinent amount and source of plant-based antioxidant material that will result in the production of GFB with desirable nutritional, sensory, and technological quality, as well as biological activity, remains a challenge to be combated by elucidation of the potential mechanism of action and by the standardization of quantification methods for antioxidant compounds.

Gluten-free diet on video platforms: Retrospective infodemiology study

Background

Video platform is an important approach for individuals to access and adopt health information. Online information on gluten-free diet (GFD) videos remains underinvestigated.

Methods

GFD videos were identified by hashtag-based searching strategy. Videos' basic information, engagement metrics, and content were recorded. Mann-Kendall test was performed to examine time trends of submitting videos and engagement metrics. Video quality was evaluated by the DISCERN instrument and the HONcode.

Results

A total of 822 videos were included in the analysis, with the majority focusing on gluten-free food recipes. The number of videos related to GFD was showing an upward trend. Engagement metrics varied between platforms and video types, with non-recipe videos receiving higher user engagement. The average DISCERN score was 50.20 out of 80 and the average HONcode score was 1.93 out of 8. Videos submitted by health professionals demonstrated better quality compared to those submitted by patients or general users.

Conclusion

There was a rise in the number of videos related to GFD on Chinese video platforms. The overall quality of these videos was poor, most of them were not rigorous enough. Highlighting using social media as a health information source has the potential risk of disseminating one-sided messages and misleading. Efforts should be made to enhance the transparency of advertisements and establish clear guidelines for information sharing on social media platforms.

Effect of a Bacterial Laccase on the Quality and Micro-Structure of Whole Wheat Bread

The gluten protein content in whole-wheat flour is low, which affects the elasticity and viscosity of the dough. Enzymatic modification of the protein may result in a network that mimics gluten, which plays an important role in the processing of whole-wheat foods. In this study, the effects of Halomonas alkaliantartica laccase (LacHa) on the quality parameters of whole-wheat bread were investigated. The optimum dosage of LacHa was 4 U/100 g of whole-wheat flour. At this dosage, whole-wheat bread exhibited the best specific volume and optimum texture parameters. Laccase also extended the storage duration of whole-wheat bread. We analyzed the micro-structure of the dough to determine its gluten-free protein extractable rate and free sulfhydryl group content, and verify that LacHa mediates cross-linking of gluten-free proteins. The results demonstrated that the cross-linking of gluten-free protein by LacHa improves the texture of whole-wheat bread. As a flour improver, LacHa has great developmental and application potential in baked-food production.

Biotechnological Potential and Safety Evaluation of Dextran- and Riboflavin-Producing Weisella cibaria Strains for Gluten-Free Baking

Gluten consumption causes several immunological and non-immunological intolerances in susceptible individuals. In this study, the dextran-producing Weissella cibaria BAL3C-5 and its derivative, the riboflavin-overproducing strain BAL3C-5 C120T, together with a commercial bakery yeast, were used to ferment gluten-free (GF)-doughs obtained from corn and rice flours at two different concentrations and supplemented with either quinoa, buckwheat, or chickpea to obtain laboratory-scale GF bread. The levels of dextran, riboflavin, and total flavins were determined in the fermented and breads. Both strains grew in fermented doughs and contributed dextran, especially to those made with corn plus quinoa (~1 g/100 g). The highest riboflavin (350-150 µg/100 g) and total flavin (2.3-1.75 mg/100 g) levels were observed with BAL3C-5 C120T, though some differences were detected between the various doughs or breads, suggesting an impact of the type of flour used. The safety assessment confirmed the lack of pathogenic factors in the bacterial strains, such as hemolysin and gelatinase activity, as well as the genetic determinants for biogenic amine production. Some intrinsic resistance to antibiotics, including vancomycin and kanamycin, was found. These results indicated the microbiological safety of both W. cibaria strains and indicated their potential application in baking to produce GF bread.

Rice-Based Gluten-Free Foods and Technologies: A Review

Rice, one of the most widely consumed staples worldwide, serves as a versatile gluten-free substitute. However, review articles on technological developments in grain-free production focusing on rice are scarce. This review assesses various research results concerning the quality attributes of rice-based gluten-free foods, including bread, pasta, and beer. To optimize the key attributes in processed products, such as dough leavening in bread and the physical and cooking properties of noodles and pasta, research has focused on blending different gluten-free grains and incorporating additives that mimic the gluten function. Additionally, various processing technologies, such as starch preprocessing and extrusion puffing processes, have been employed to boost the quality of rice-based gluten-free products. Today, a variety of products, including bread, noodles, and beer, use rice as a partial replacement for barley or wheat. With rapid advancements in technology, a noticeable portion of consumers now shows a preference for products containing rice as a substitute. This trend indicates that rice-based gluten-free foods can be enhanced by leveraging the latest developments in gluten-free product technologies, particularly in countries where rice is a staple or is predominantly cultivated.

Current status and future prospects of sensory and consumer research approaches to gluten-free bakery and pasta products

Sensory and consumer research performs a pivotal role in gluten-free (GF) food research and development due to consumer dissatisfaction about currently available products, despite the continued growth of this market and promising research developments. Nowadays, almost half of the original articles about GF products include sensory analysis. A current overview is needed to help both food scientists and industry indentify current trends and forward-looking approaches. This current review has gathered information concerning sensory and consumer research for GF bakery and pasta products, from studies published in the last decade, and then discusses future challenges in the light of recent advances. Among the promising approaches, projective techniques that collect data using social media can provide quick, spontaneous and direct opinions from GF consumers. They can also be used to evaluate trends and cross-cultural or global insights. Participatory methods have highlighted the importance of label information and may further explore the behavior of GF consumers in more realistic environments, as well as to evaluate the intrinsic GF food factors in GF consumer opinions, emotions, behavior and choices. This review details current issues occurring in sensory analysis of GF products, which still need to be resolved. The combination of affective and analytical methods allows for a better characterization of the samples and such sensory analysis of GF products in the future could guide product development and quality control, overcoming technological, nutritional, and shelf-life issues.

Gluten-Free Product Recalls and Their Impact on Consumer Trust

The range of gluten-free food products available to consumers is steadily expanding. In recent years, recalls of food products have highlighted the importance of accurate labeling of food products for the presence of wheat, other gluten-containing cereals, or gluten itself as refined ingredient. The purpose of this study was to gain more insights into recent food recalls related to undeclared gluten/wheat contamination and consumer experiences with these recalls. Recalls of products triggered by gluten contamination are relatively scarce and are not often triggered by a consumer complaint. The impact of these recalls on consumer trust was evaluated through an online survey that was distributed among supporters of Celiac Canada (CCA) and covered (i) strategies to adhere to a gluten-free diet, (ii) experiences with gluten-free recalls and their impact on consumer trust, and (iii) demographic information. Consumer concern regarding gluten-free product recalls is significant, but the concern regarding recalls is not heightened after experiencing a recall. Companies pursuing transparency in the process, identification of the source of contamination, and mitigation strategies going forward are likely to retain consumer trust in their product and brand. Based on the survey results, further efforts focusing on consumer education regarding interpreting nutrient labels, identifying sources of information on product recalls, and understanding procedures to follow upon suspected gluten contamination of a gluten-free product are recommended.

Mapping the knowledge structure of a gluten-free diet: a global perspective

Background

A gluten-free diet (GFD) has become one of the most popular eating plans and is essential for managing gluten-related medical conditions, signs, and symptoms. Therefore, we performed a bibliometric analysis of the scientific literature on the GFD to describe the research landscape.

Methods

The Scopus database was searched for publications on the GFD from 1952 to 2021. A bibliometric analysis of the data was performed. VOSviewer software was used to perform visualization analysis, co-occurrence analysis, and publication trends in GFD.

Results

A total of 3,258 publications were retrieved. In terms of publications, Italy (n = 468, 14.36%) led in the number of publications, followed by the USA (n = 398, 12.22%) and Spain (n = 274, 8.41%). The retrieved documents earned an average of 22.89 citations per document, for a total of 74,560 citations. Since 2001, there has been a gradual growth in the number of articles published, going from 23 to more than 370 in 2021. Using the mapping terms in the title/abstract a minimum of 50 times, 291 terms were divided into two main clusters: ‘adherence to a gluten-free diet in celiac disease’ and ‘improvement of the nutritional and sensory quality of gluten-free products.’

Conclusions

Over the past six decades, there has been a growing need for gluten-free bakery products and a noticeable increase in related publications. This study indicates that the “improvement of the nutritional and sensory quality of gluten-free products” will remain a hotspot in this research field for upcoming years.

Walnut Flour as an Ingredient for Producing Low-Carbohydrate Bread: Physicochemical, Sensory, and Spectroscopic Characteristics

Walnut flour (WF) is a nutrient-rich source that can be used as an alternative for individuals on a gluten-free diet. This study aimed to assess the physical, chemical, and sensory changes in low-carbohydrate bread when supplemented with WF. Molecular-level changes were also examined using ATR-FTIR spectra. The bread recipe, containing buckwheat and flaxseed, was enriched with WF at levels ranging from 5% to 20%. The addition of WF resulted in increased loaf volume and decreased baking loss. Enriched bread samples showed higher protein content, while fat and available carbohydrate content decreased. Additionally, WF incorporation led to a decrease in crumb brightness and an increase in redness (from 23.1 to 25.4) and yellowness (from 23.8 to 26.7). WF also increased crumb hardness and chewiness. Moreover, the tested additives primarily influenced the intensity of FTIR spectra, indicating changes in protein, carbohydrate, and fat content, with increased band intensity observed in the protein region. We particularly recommend bread with a WF content of 15%. This type of bread is characterized by high consumer acceptance. Furthermore, compared to bread without the addition of WF, it has a higher content of phenolic compounds, protein, and fat by approximately 40%, 8%, and 4%, respectively. The antioxidant activity of this bread, determined using the ABTS and DPPH methods, is also significantly higher compared to the control bread.

The Rationale for Sulforaphane Favourably Influencing Gut Homeostasis and Gut-Organ Dysfunction: A Clinician's Hypothesis

Given the increasing scientific, clinical and consumer interest in highly prevalent functional gastrointestinal disorders, appropriate therapeutic strategies are needed to address the many aspects of digestive dysfunction. Accumulating evidence for the crucifer-derived bioactive molecule sulforaphane in upstream cellular defence mechanisms highlights its potential as a therapeutic candidate in targeting functional gastrointestinal conditions, as well as systemic disorders. This article catalogues the evolution of and rationale for a hypothesis that multifunctional sulforaphane can be utilised as the initial step in restoring the ecology of the gut ecosystem; it can do this primarily by targeting the functions of intestinal epithelial cells. A growing body of work has identified the colonocyte as the driver of dysbiosis, such that targeting gut epithelial function could provide an alternative to targeting the microbes themselves for the remediation of microbial dysbiosis. The hypothesis discussed herein has evolved over several years and is supported by case studies showing the application of sulforaphane in gastrointestinal disorders, related food intolerance, and several systemic conditions. To the best of our knowledge, this is the first time the effects of sulforaphane have been reported in a clinical environment, with several of its key properties within the gut ecosystem appearing to be related to its nutrigenomic effects on gene expression.

The Effect of Enrichment with Sour-Cherry Extracts on Gluten-Free Snacks Developed by Novel 3D Technologies

Gluten-free formulations (GF) were utilized as food inks enriched with sour-cherry powder (SCP) and lyophilized extract (SCLE), and their physicochemical, rheological, and thermomechanical properties were evaluated with respect to different leavening conditions. Post-printing drying was also assessed in terms of texture, color, and phenolic substances. SCP and SCLE enrichment decreased lightness by 15% and increased red hue by almost 30%, mainly in yeast formulations. SC addition reduced pH by more than 12% for SCP in both leavening conditions and at 10% to 12% for SCLE, depending on leavening agents. The SCLE addition doubled dynamic moduli and complex viscosity magnitudes and increased hardness at 75.7% compared to the control for baking-powder formulations. SC enrichment, compared to the control, increased the phenolic sum to more than 90% (87% SCLE, 96% SCP) in yeast formulations, presenting lower values (almost 70%) for baking powder. Antioxidant activity in 3D-printed snacks was positively influenced by SC incorporation, depending on the drying and leavening treatment. Phenolic content, in terms of total phenolic sum, origin, and composition, possibly impacts the product's antioxidant activity by depicting antagonistic or synergistic phenomena. Ultimately, 3D printing is feasible for producing functional GF snacks enriched with sour-cherry extracts.

Heavy Metal and Rice in Gluten-Free Diets: Are They a Risk?

A gluten-free diet (GFD) is the treatment of choice for gluten-related disorders. It has been associated with macro- and micronutrient deficiencies. Recently, consumption of arsenic-contaminated rice has raised concern because of the potential greater risk that it may represent for people on GFDs, whose rice consumption is high, since it is a fundamental cereal in GFDs. We reviewed the data published over the last 20 years in Medline and Scielo, in English, French and Spanish, on four metals (As, Hg, Cd, and Pb), to assess whether the evidence suggests that celiac disease or consumption of a GFD is associated with increased levels of blood/urinary metal concentrations. The review revealed a few articles that were directly related to the four metals and their relationships with a GFD. The evidence supports that rice-based products are a relevant source of As and other metals. Clinical studies and evaluations based on NHANES have indicated that persons on GFDs have higher As and Hg blood/urinary levels, suggesting that the diet and not the disease is responsible for it. The levels described are statistically significant compared to those of persons on complete diets, but far from toxic levels. The question of whether higher exposure to heavy metals associated with a GFD is biologically relevant remains unanswered and deserves study.

Sustainable Strategies for Increasing Legume Consumption: Culinary and Educational Approaches

Legumes are nutrient-dense crops with health-promoting benefits. However, several barriers are associated with their consumption. Emerging issues including food neophobic tendencies or taboos, unclear dietary guidelines on legume consumption, health concerns, and socio-economic reasons, as well as long cooking procedures, adversely affect legume consumption frequency. Pre-treatment methods, including soaking, sprouting, and pulse electric field technology, are effective in reducing the alpha-oligosaccharides and other anti-nutritional factors, eventually lowering cooking time for legumes. Extrusion technology used for innovative development of legume-enriched products, including snacks, breakfast cereals and puffs, baking and pasta, represents a strategic way to promote legume consumption. Culinary skills such as legume salads, legume sprouts, stews, soups, hummus, and the development of homemade cake recipes using legume flour could represent effective ways to promote legume consumption. This review aims to highlight the nutritional and health effects associated with legume consumption, and strategies to improve their digestibility and nutritional profile. Additionally, proper educational and culinary approaches aimed to improve legumes intake are discussed.

Consumer Awareness and Acceptance of Biotechnological Solutions for Gluten-Free Products

Celiac disease is an immune-mediated disorder caused by the ingestion of gluten proteins. The gluten-free diet is currently the only therapy to achieve the symptoms' remission. Biotechnological approaches are currently being explored to obtain safer and healthier food for celiacs. This article analyzes consumer awareness and acceptance of advanced biotechnologies to develop gluten-free products. An online snowball sampling questionnaire was proposed to 511 Italian participants, selected among celiac and non-celiac people, from December 2020 to January 2021, during the second wave of the COVID-19 pandemic. Overall, 64% of respondents favor food biotechnology, as long as it has benefits for health or the environment. Moreover, biotechnology perception differs according to education level and type. A total of 65% of the survey participants would taste gluten-free products obtained through a biotechnological approach, and 57% would buy them at a higher price than the current market price. Our results show a change in public opinion about the usefulness of food biotechnology and its moral acceptability compared to 20 years ago. However, the study of public opinion is very complex, dealing with individuals with social, economic, and cultural differences. Undoubtedly, the scientific dissemination of genetic biotechnologies must be more effective and usable to increase the level of citizens' awareness.

Oral bioavailability of bioactive compounds; modulating factors, in vitro analysis methods, and enhancing strategies

Foods are complex biosystems made up of a wide variety of compounds. Some of them, such as nutrients and bioactive compounds (bioactives), contribute to supporting body functions and bring important health benefits; others, such as food additives, are involved in processing techniques and contribute to improving sensory attributes and ensuring food safety. Also, there are antinutrients in foods that affect food bioefficiency and contaminants that increase the risk of toxicity. The bioefficiency of food is evaluated with bioavailability which represents the amount of nutrients or bioactives from the consumed food reaching the organs and tissues where they exert their biological activity. Oral bioavailability is the result of some physicochemical and biological processes in which food is involved such as liberation, absorption, distribution, metabolism, and elimination (LADME). In this paper, a general presentation of the factors influencing oral bioavailability of nutrients and bioactives as well as the in vitro techniques for evaluating bioaccessibility and is provided. In this context, a critical analysis of the effects of physiological factors related to the characteristics of the gastrointestinal tract (GIT) on oral bioavailability is discussed, such as pH, chemical composition, volumes of gastrointestinal (GI) fluids, transit time, enzymatic activity, mechanical processes, and so on, and the pharmacokinetics factors including BAC and solubility of bioactives, their transport across the cell membrane, their biodistribution and metabolism. The impact of matrix and food processing on the BAC of bioactives is also explained. The researchers' recent concerns for improving oral bioavailability of nutrients and food bioactives using both traditional techniques, for example, thermal treatments, mechanical processes, soaking, germination and fermentation, as well as food nanotechnologies, such as loading of bioactives in different colloidal delivery systems (CDSs), is also highlighted.

Nutritional, textural and sensory properties of lasagna dough containing air yam, a non-conventional edible plant

The incorporation of non-conventional edible plants into gluten-free food products shows potential and the ability to increase nutritional properties. Therefore, the aim of this study was to develop a gluten-free air yam-based lasagna dough and to evaluate the nutritional, textural, and sensory properties. First, the air yam flour was obtained by drying the tubers at 55 °C for 16 h and then, mixed with the water and egg powder, it constituted the lasagna dough. The nutritional composition and bioaccessible mineral content of air yam flour and lasagna dough were evaluated, as well as the texture, microbiological and sensory properties of the lasagna dough. The results indicated that air yam flour and the lasagna dough had high dietary fiber contents, 17.1% and 9.4%, respectively. Additionally, the low-fat content found means that the lasagna dough can be considered both gluten-free and fat-free. The most bioaccessible mineral present was K in both air yam flour and lasagna dough. In sensory analysis, the lasagna dough containing air yam showed an intermediate acceptability in relation to two already commercialized lasagna doughs. This study shows an application to this group of plants that are still little explored, allowing the development to consumers and industries.

Graphical abstract

Screening and Application of Novel Homofermentative Lactic Acid Bacteria Results in Low-FODMAP Whole-Wheat Bread

FODMAPs are fermentable oligo-, di-, monosaccharides, and polyols. The application of homofermentative lactic acid bacteria (LAB) has been investigated as a promising approach for producing low-FODMAP whole-wheat bread. The low-FODMAP diet is recommended to treat irritable bowel syndrome (IBS). Wheat flour is staple to many diets and is a significant source of fructans, which are considered FODMAPs. The reduction of fructans via sourdough fermentation, generally associated with heterofermentative lactic acid bacteria (LAB), often leads to the accumulation of other FODMAPs. A collection of 244 wild-type LAB strains was isolated from different environments and their specific FODMAP utilisation profiles established. Three homofermentative strains were selected for production of whole-wheat sourdough bread. These were Lactiplantibacillus plantarum FST1.7 (FST1.7), Lacticaseibacillus paracasei R3 (R3), and Pediococcus pentosaceus RYE106 (RYE106). Carbohydrate levels in flour, sourdoughs (before and after 48 h fermentation), and resulting breads were analysed via HPAEC-PAD and compared with whole-wheat bread leavened with baker’s yeast. While strain R3 was the most efficient in FODMAP reduction, breads produced with all three test strains had FODMAP content below cut-off levels that would trigger IBS symptoms. Results of this study highlighted the potential of homofermentative LAB in producing low-FODMAP whole-wheat bread.

Optimization of tannin-containing sorghum bran addition to gluten-free bread

Ingredients used to enhance sensory quality of gluten-free (GF) bread often lack in nutrients. This presents nutritional challenges for celiac-positive individuals and fails to meet expectations of healthfulness for non-celiac GF consumers. Sorghum (Sorghum bicolor L. Moench) flour can provide acceptable GF bread properties, and tannin-containing varieties contain antioxidants concentrated in the bran along with dietary fiber. Using a central composite design, tannin-containing sumac sorghum bran, gum (xanthan + guar), and water levels were optimized in a GF sorghum-based bread formulation. Loaf specific volume and gas cells/cm² were maximized while minimizing hardness and cell wall thickness. The optimum formulation containing 14.2% sorghum bran, 1% gum, and 145% water (flour basis) effectively increased dietary fiber in bread to 13.4% (considered "high fiber") and showed oxygen radical absorbance capacity of 61.6 µmol TE/g. This optimum formulation did not differ from a sorghum flour-based control bread in consumers' (N = 100) liking of color, texture, flavor, overall acceptability, nor willingness to buy (WTB). All mean hedonic scores (numbered 9-point scale) were above 5, whereas average WTB was 4.7 for the optimum formulation and 4.6 for the control (9-point Likert scale) among consumers varying in GF bread consumption habits. Perceived bread bitterness was low (averaging 2.85 on 9-point intensity scale), did not vary between samples despite marked differences in antioxidant capacity, and was not correlated with WTB. When utilizing effective optimization models with key functional ingredients, sumac sorghum bran addition can enhance dietary fiber and antioxidant potential in sorghum-based GF breads without compromising quality attributes.

Application of inulin in bread: A review of technological properties and factors affecting its stability

Due to its dual function, inulin is an important prebiotic compound in the cereal industry, especially in bread production. In other words, improving technological features and creating health properties (such as reducing the risk of type 2 diabetes, heart disease, metabolic syndrome, and osteoporosis) have led to the widespread use of this compound. Inulin has many important technological functions in bread, including its ability to interact with water, create structure, and influence rheological properties, texture, and overall acceptability of the final product. Nevertheless, bread processing conditions can influence the structural integrity of inulin and thus affect its technological efficiency. Therefore, this review article aims to investigate the technological properties and factors affecting the stability of inulin during bread processing conditions. Generally, the addition of inulin could considerably improve the technical performance of bread. However, the stability of inulin depends on the formulation components, type of fermentation, and baking process.

Children With Celiac Disease Consume Specific Food Additives More Frequently Compared to Children Without Celiac Disease

BACKGROUND

Gluten-free foods often contain food additives to improve palatability, but the long-term effects on the human gastrointestinal tract are not well known.

AIMS

This study aimed to quantify frequency of food additive exposure in children with and without celiac disease (CD).

METHODS

Children with and without CD were enrolled and demographic data and three-day diet records were obtained. Foods were classified as gluten-free products (GFP) and "processed food", and were evaluated for presence of select food additives: polysorbate 80, carboxymethylcellulose, xanthan gum, guar gum, soy lecithin, titanium dioxide, carrageenan, maltodextrin, and aluminosilicates. The frequency of exposure was described.

RESULTS

Twenty-eight participants were included in final analysis. Children with CD had a higher number of daily exposures to xanthan gum (5.3 ± 3.1 vs 2.3 ± 2.4; p = 0.009), but similar exposures to the other additives. GFP contributed 29% of total calories in the GF diet. Both groups had similar intake of processed foods. Comparing GFP and gluten-containing processed foods, 68% vs. 25% contained at least one food additive of interest (p < 0.0001); in the celiac group, those with higher consumption of GFP tended to have a higher frequency of exposure to food additives (p = 0.09).

CONCLUSION

A gluten-free diet and consumption of GFP may contribute to differences in food additive intake; quantifying food additive exposures and their effect on humans requires further study.

Evaluation of Gluten Exclusion for the Improvement of Rheumatoid Arthritis in Adults

There is currently a growing anti-gluten trend which, except for individuals with coeliac disease and non-coeliac gluten sensitivity (NCGS) for whom its intake is contraindicated, results in gluten (the main protein in wheat and other cereals) being considered harmful to health and excluded from diets, largely due to information distributed through social networks. However, in many cases the recommendation to exclude gluten from the diet goes beyond personal choice and is promoted by health professionals. This choice and/or recommendation is especially important to individuals with chronic inflammatory diseases such as rheumatoid arthritis (RA), for which this exclusion is justified to reduce the symptoms of the disease. The aim of this literature review is to assess whether there is scientific evidence to justify the elimination of gluten in patients with RA, neither coeliac nor with NCGS, to improve their symptoms and quality of life. The results of the search on gluten and RA carried out in the Embase database and the extraction of data from 16 articles included in the review are presented. No scientific evidence was found to recommend the exclusion of gluten in patients with RA.

Food Insecurity Negatively Impacts Gluten Avoidance and Nutritional Intake in Patients With Celiac Disease

BACKGROUND

Food insecurity is a major public health challenge. For patients with celiac disease (CeD), food insecurity may be particularly detrimental as it threatens the cornerstone of their treatment: adoption of a gluten-free diet (GFD). We aimed to characterize the prevalence of food insecurity in patients with CeD and evaluate its impact on GFD adoption and nutritional intake.

METHODS

We analyzed data from patients with CeD participating in the US National Health and Nutrition Examination Survey (NHANES) from 2009 to 2014. Food insecurity was defined using the US Department of Agriculture 18-Item Standard Food Security Survey Module. Survey-weighted logistic regression was used to assess differences in demographic characteristics of CeD patients living with food insecurity and the impact of food security on GFD adoption. Multivariable survey-weighted linear regression was used to evaluate the effect of food insecurity on nutritional intake of macronutrients and micronutrients.

RESULTS

Overall, 15.9% (95% confidence interval: 10.6%, 23.1%) of patients with CeD in the United States [weighted N=2.9 million (95% confidence interval: 2.2, 3.5 million)] are food insecure. Food insecure patients with CeD were disproportionately younger, poorly educated, nonwhite, living in poverty, and were significantly less likely to adopt a GFD (24.1% vs. 67.9%, P =0.02). Food insecurity was associated with significantly lower consumption of protein, carbohydrates, fat, and most vitamins and minerals.

CONCLUSIONS

One in 6 patients with CeD are food insecure, negatively impacting GFD adoption and the ability to meet recommended daily intake of most micronutrients. Less than one quarter of food insecure CeD patients adhere to a GFD.

Quinoa Snack Production at an Industrial Level: Effect of Extrusion and Baking on Digestibility, Bioactive, Rheological, and Physical Properties

This research aimed to produce gluten-free snacks on a pilot scale from quinoa flour. These snacks experienced an extrusion process, followed by baking. The effects of these technological processes on carbohydrate and protein digestibility, extractable phenolic compounds (EPP), hydrolyzable phenolic compounds (HPP), antioxidant capacity, and physical properties were evaluated in raw quinoa flour and extruded snacks. Extrusion increased digestible starch (RDS) from 7.33 g/100 g bs to 77.33 g /100 g bs. Resistant starch (RS) showed a variation of 2 g/100 g bs. It is noteworthy that protein digestibility increased up to 94.58 g/100 bs after extrusion and baking. These processes increased HPP content, while EPP and carotenoid content decreased. The samples showed significant differences (p < 0.05) in the antioxidant properties determined through the DPPH and ABTS methods. Values of 19.72 ± 0.81 µmol T/g were observed in snacks and 13.16 ± 0.2 µmol T/g in raw flour, but a reduction of up to 16.10 ± 0.68 µmol T/g was observed during baking. The baking process reduced the work of crispness (Wcr) from 0.79 to 0.23 N.mm, while the saturation (C*) was higher in baked ones, showing higher color intensity. The baking process did not influence the viscosity profile. The results in this study respond to the growing interest of the food industry to satisfy consumer demand for new, healthy, and expanded gluten-free snacks with bioactive compounds.

The Update of the Italian Food Composition Database of Gluten-Free Products and Its Application in Food-Based Dietary Guidelines Menus

Complete food composition databases (FCDBs) on gluten-free (GF) foods are needed to assess the nutrient intakes of celiac disease patients. The aim of the present work was to update the previously developed version of the Italian GF-FCDB and to apply it to a theoretical GF diet. The updated GF-FCDB includes the composition of 108 GF cereal-based foods, as sold, in terms of energy and macro- and micro-nutrients, imputed using food label information combined with the standard recipe approach. Three scenarios (i.e., refined, mixed, and wholegrain cereals) of the weekly guideline menu for the general Italian population were analyzed for energy and nutrient content in a theoretical dietary assessment using traditional gluten-containing (GC) foods and the corresponding GF substitutes. All GF menus were higher than the corresponding GC menus in polyunsaturated fatty acids, linoleic acid, and vitamin E. Zinc was lower in GF than in GC menus only in the wholegrain-cereal scenario. Thanks to the application of the updated GF-FCDB including a comprehensive list of micronutrients, we observed that it is possible for celiac disease patients to meet nutrient requirements by simply substituting GC with GF cereal-based products following recommendations for the general population.

Unprocessed wheat γ-gliadin reduces gluten accumulation associated with the endoplasmic reticulum stress and elevated cell death

Along with increasing demands for high yield, elite processing quality and improved nutrient value in wheat, concerns have emerged around the effects of gluten in wheat-based foods on human health. However, knowledge of the mechanisms regulating gluten accumulation remains largely unexplored. Here we report the identification and characterization of a wheat low gluten protein 1 (lgp1) mutant that shows extremely low levels of gliadins and glutenins. The lgp1 mutation in a single γ-gliadin gene causes defective signal peptide cleavage, resulting in the accumulation of an excessive amount of unprocessed γ-gliadin and a reduced level of gluten, which alters the endoplasmic reticulum (ER) structure, forms the autophagosome-like structures, leads to the delivery of seed storage proteins to the extracellular space and causes a reduction in starch biosynthesis. Physiologically, these effects trigger ER stress and cell death. This study unravels a unique mechanism that unprocessed γ-gliadin reduces gluten accumulation associated with ER stress and elevated cell death in wheat. Moreover, the reduced gluten level in the lgp1 mutant makes it a good candidate for specific diets for patients with diabetes or kidney diease.

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.

Development of a Canadian Food Composition Database of Gluten-Free Products

Country-specific food composition data are needed for gluten-free (GF) food products to assess nutritional adequacy and diet quality. This research aimed to develop a comprehensive GF food composition database for key GF foods consumed in Canada. Average nutrient data from 167 products were estimated from Nutrition Fact Panel labels and the commercial ingredient list, using an iterative and systematic approach. The database reports mean values for energy and 29 nutrients per 100 g for 33 GF commercial grain-based foods. Nutrient values were evaluated with Health Canada’s nutrient content claims per standard reference serving. On average, GF products were, at minimum, a source of thiamin (73%), riboflavin (70%), niacin (58%), iron (58%), fibre (55%), magnesium (48%), folate (36%), zinc (19%), and calcium (15%). Most GF products were low in saturated fat (85%) and cholesterol (64%) but only 15% were low in total fat and 6% were free of sugar. Micronutrient enrichment and the use of nutrient-dense whole grain flours, legume flours, oil seed husks, and functional fibre ingredients varied within and between categories and brands but appeared to contribute to nutrient content. This database provides a new tool to enhance GF diet assessment in individuals or populations in Canada.

Dietary Acid Load in Gluten-Free Diets: Results from a Cross-Sectional Study

The gluten-free diet (GFD) ensures improvement of clinical symptoms in the vast majority of celiac disease (CD) patients. Despite stable CD rates in many countries, an increasing number of healthy individuals are adopting gluten-free diets, believing that this diet is an inherently healthier choice. The health effects of gluten-free diets are controversial, and a recent study added to the debate by reporting a lower acidogenic potential of this diet. The effects of the GFD on potential renal acid load (PRAL) and net endogenous acid production (NEAP)—two important markers of dietary acid load (DAL)—are poorly understood, and have never been examined in a Western population. Using cross-sectional data from the National Health and Nutrition Examination Surveys, we estimated DAL in U.S. individuals reporting a GFD and contrasted the results to the general U.S. population consuming gluten and denying special diets. The GFD was associated with significantly lower crude DAL scores, and after adjustments for confounders in multivariate regression, the results remain significant. Yet, our study could not confirm the reported alkalizing properties of the GFD. Although overall DAL scores were significantly lower in the GFD group, they were comparable to Western diets producing 50–75 mEq of acid per day.

Detection of Gluten in Gluten-Free Foods of Plant Origin

The work deals with the issue of standardization and more accurate methodology for the isolation of gluten DNA in gluten-free products of plant origin, which is more demanding due to the more complex structure of plant cells. Three isolation methods were compared, of which the combination of glass and zirconium beads, Proteinase K and a commercially produced isolation kit was confirmed to be the most effective procedure. The given isolation procedure was more effective in one-component gluten-free foods, where the concentration of the obtained DNA ranged from 80.4 ± 0.7 to 99.0 ± 0.0 ng/µL. The subsequent PCR reaction revealed the presence of gluten not only in guaranteed gluten-free products (40%), but also in naturally gluten-free foods (50%). These were mainly gluten-free sponge cakes, gluten-free biscuits "Cranberries", cocoa powder, coffee "3in1", and instant coffee.