A comparative study of different bio-processing methods for reduction in wheat flour allergens

Allergenicity of wheat protein in diet: Mechanisms, modifications and challenges

Wheat is widely available in people's daily diets. However, some people are currently experiencing IgE-mediated allergic reactions to wheat-based foods, which seriously impact their quality of life. Thus, it is imperative to provide comprehensive knowledge and effective methods to reduce the risk of wheat allergy (WA) in food. In the present review, recent advances in WA symptoms, the major allergens, detection methods, opportunities and challenges in establishing animal models of WA are summarized and discussed. Furthermore, an updated overview of the different modification methods that are currently being applied to wheat-based foods is provided. This study concludes that future approaches to food allergen detection will focus on combining multiple tools to rapidly and accurately quantify individual allergens in complex food matrices. Besides, biological modification has many advantages over physical or chemical modification methods in the development of hypoallergenic wheat products, such as enzymatic hydrolysis and fermentation. It is worth noting that using biotechnology to edit wheat allergen genes to produce allergen-free food may be a promising method in the future which could improve the safety of wheat foods and the health of allergy sufferers.

Effect of Different Processing Methods on Quality, Structure, Oxidative Properties and Water Distribution Properties of Fish Meat-Based Snacks

Snack foods are consumed around to globe due to their high nutrition, taste and versatility; however, the effects of various processing methods on quality, structure and oxidative properties are scare in the literature. This study aims to evaluate the effect of various processing methods (frying, baking and microwave cooking) on quality, structure, pasting, water distribution and protein oxidative properties of fish meat-based snacks. The results showed that the frying method induced a significantly (p < 0.05) higher expansion than baking and microwave methods. Texture in terms of hardness was attributed to the rapid loss of water from muscle fiber, which resulted in compact structure and the increased hardness in microwave cooking, whereas in frying, due to excessive expansion, the hardness decreased. The pasting properties were significantly higher in baking, indicating the sufficient swelling of starch granules, while low in microwave suggest the rapid heating, which degraded the starch molecules and disruption of hydrogen bonds as well as glycosidic linkage and weakening of granules integrity. The water movement assessed by Low Field Nuclear Magnetic Resonance (LF-NMR) showed that frying had less tight and immobilized water, whereas microwave and baking had high amounts of tight and immobilized water, attributing to the proper starch-protein interaction within matrix, which was also evidenced by scanning electron microscopy (SEM) analysis. The protein oxidation was significantly (p < 0.05) higher in frying compared to baking and microwave cooking. The findings suggest the endorsement of baking and microwave cooking for a quality, safe and healthy snacks.

Characterizing the Rheological and Bread-Making Properties of Wheat Flour Treated by "Gluten FriendlyTM" Technology

After discovering an innovative technology for the reshaping of gluten proteins—the “Gluten Friendly^TM” system—that confers to wheat flour some unprecedented characteristics, such as reduced epitope antigenicity and a positive modulation of the gut microbiota, its effects on the production and quality of bread have been studied. Mainly, we have investigated the chemical, rheological and pasting properties of Gluten Friendly Flour (GFF) and of control flour (CF) with the aim of analyzing and interpreting potential differences. Furthermore, the bread made from GFF and CF was evaluated in terms of microstructure properties and sensory quality. The experiments demonstrated that GFF became soluble in aqueous solution, making it unfeasible to isolate using the Glutomatic apparatus. Although the water absorption of GFF increased by 10% compared to CF, dough elasticity was reduced, and dough stability decreased from 5 to 2 min. A significant increase in the alveograph index (P/L) from 0.63 to 6.31 was detected, whereas pasting properties did not change from the control flour. Despite these profound modifications in the rheological properties, GFF exhibited a high ability to shape dough and to produce bread with high quality and negligible differences from the control bread in terms of appearance, taste, aroma, color and texture.

Non-animal proteins as cutting-edge ingredients to reformulate animal-free foodstuffs: Present status and future perspectives

Consumer interest in protein rich diets is increasing, with more attention being paid to the protein source. Despite the occurrence of animal proteins in the human diet, non-animal proteins are gaining popularity around the world due to their health benefits, environmental sustainability, and ethical merit. These sources of protein qualify for vegan, vegetarian, and flexitarian diets. Non-animal proteins are versatile, derived mainly from cereals, vegetables, pulses, algae (seaweed and microalgae), fungi, and bacteria. This review's intent is to analyze the current and future direction of research and innovation in non-animal proteins, and to elucidate the extent (limitations and opportunities) of their applications in food and beverage industries. Prior knowledge provided relevant information on protein features (processing, structure, and techno-functionality) with particular focus on those derived from soy and wheat. In the current food landscape, beyond conventionally used plant sources, other plant proteins are gaining traction as alternative ingredients to formulate animal-free foodstuffs (e.g., meat alternatives, beverages, baked products, snack foods, and others). Microbial proteins derived from fungi and algae are also food ingredients of interest due to their high protein quantity and quality, however there is no commercial food application for bacterial protein yet. In the future, key points to consider are the importance of strain/variety selection, advances in extraction technologies, toxicity assessment, and how this source can be used to create food products for personalized nutrition.

Effects of microwave treatment of durum wheat kernels on quality characteristics of flour and pasta

The influence of microwave treatment of hydrated durum wheat kernels of two different cultivars (cv Aureo and Sfinge), on wholemeal flour and pasta quality was addressed. Size exclusion-HPLC and electrophoresis analysis were used to investigate changes in the gluten network arrangement as affected by the microwave treatment. Rheological properties of dough, cooking quality and sensory properties of pasta were also assessed. Results suggested that the microwave treatment on hydrated durum wheat kernels blocks gluten protein conformation through SS bonds formation and the free -SH are no longer able to create a strong network during pasta processing, due to the conformational changes. Rheological study of dough confirmed that the modifications induced by microwave treatment greatly affected pasta making characteristics of wheat flour, with significant negative consequences on product quality, especially for pasta cooking quality. Pasta from treated durum wheat showed low sensory quality, mainly due to high bulkiness and adhesiveness.

Phosphorylation and Enzymatic Hydrolysis with Alcalase and Papain Effectively Reduce Allergic Reactions to Gliadins in Normal Mice

Gliadins are major allergens responsible for wheat allergies. Food processing is an effective strategy to reduce the allergenicity of gluten. In the present study, we determined the secondary and tertiary structures of gluten and gliadins treated by chemical, physical, and enzymatic means through FTIR, surface hydrophobicity, intrinsic fluorescence spectra, and UV absorption spectra. The results showed that the three treatments of phosphorylation and alcalase and papain hydrolyses significantly changed the conformational structures of gliadins, especially the secondary structure. Then, the potential allergenicity of the phosphorylated and alcalase and papain hydrolyzed gliadins were further characterized, and we observed a significant decrease in the allergenicity through the results of the index of spleen, serum total IgE, gliadin-specific IgE, histamine, and serum cytokine concentrations. An elevation of Th17 cells, the absence of Treg cells, and an imbalance in Treg/Th17 are associated with allergy. On the basis of the expression levels of related cytokines and key transcription factors, we also confirmed that phosphorylation and alcalase and papain hydrolysis could effectively reduce the allergenicity of gliadins by improving the imbalance of both Th1/Th2 and Treg/Th17 in the spleens of sensitized mice. This study suggested that the changes in conformational structure contribute to gliadin hyposensitization and that phosphorylation and alcalase and papain hydrolysis may be promising strategies for the production of wheat products with low allergenicity.

Effectiveness of proteolytic enzymes to remove gluten residues and feasibility of incorporating them into cleaning products for industrial purposes

The development of protocols for efficient gluten elimination is one of the most critical aspects of any allergen management strategy in the industry. The suitability of different proteolytic enzymes to be included in a cleaning formulation that allows the effective elimination of gluten residues was studied. Alcalase (ALC), neutrase (NEUT) and flavourzyme (FLAV) were selected from in silico analysis. The presence of 1% (v/v) of linear alkylbenzene sulphonate (LAS), a common anionic detergent, improved the gluten solubility, which may favour its elimination. Chromatographic analysis showed that the three enzymes studied were able to hydrolyse gluten in the presence of LAS. The highest percentage of short peptides (< 5 kDa) was achieved with ALC, what increases the probability of reducing the gluten antigenicity. Besides, in the presence of ALC and detergent LAS have detected the lowest levels of gluten with ELISA kits. So, effective amounts of ALC and LAS were added to a cleaning formulation, where its proteolytic activity was maintained above 90% after 37 days at 4 °C and 25 °C (under dark). Preliminary validation of the effectiveness enzymatic cleaning formulation to hydrolyse gluten was performed in a ready-to-eat/frozen food company, in which previous episodes of cross-contamination with gluten have been detected. The gluten content decreased to values below 0.125 μg/100 cm² when the cleaning formulation was tested on different surfaces with different cleaning protocols, demonstrating the high suitability of the enzymatic cleaning formulation developed.

Effects of microwave heating of wheat on its functional properties and accelerated storage

The effect of microwave heating wheat grains (700 W for 0-60 s) on gluten, farinograph, pasting properties and baking (steamed bread and biscuit) of flour was studied. The lipase (LA) and lipoxygenase (LOX) activities of the microwave-treated wheat were monitored, and the accelerated storage at 35 °C of whole wheat flour was also investigated. The results showed that the gluten, farinograph properties and viscosity were influenced to a small extent when microwave treatment time was less than or equal to 20 s and the temperature of the grains was less than or equal to 56 °C. Texture profile analysis indicated that steamed bread made from wheat treated by microwave for 20 s was softer and of better quality. Microwave treatment for longer periods (≥30 s) increased the temperature ≥68 °C, that damaged the gluten and made wheat unsuitable for making steamed bread; however, suitable for making food with lower gluten requirements, such as biscuits. The results obtained from enzyme activity and accelerated storage experiments demonstrated that microwave treatment could inactivate LA and LOX and extend the shelf-life.

Effects of grain species and cultivar, thermal processing, and enzymatic hydrolysis on gluten quantitation

Gluten from wheat, rye, and barley can trigger IgE-mediated allergy or Celiac disease in sensitive individuals. Gluten-free labeled foods are available as a safe alternative. Immunoassays such as the enzyme-linked immunosorbent assay (ELISA) are commonly used to quantify gluten in foods. However, various non-assay related factors can affect gluten quantitation. The effect of gluten-containing grain cultivars, thermal processing, and enzymatic hydrolysis on gluten quantitation by various ELISA kits was evaluated. The ELISA kits exhibited variations in gluten quantitation depending on the gluten-containing grain and their cultivars. Acceptable gluten recoveries were obtained in 200mg/kg wheat, rye, and barley-spiked corn flour thermally processed at various conditions. However, depending on the enzyme, gluten grain source, and ELISA kit used, measured gluten content was significantly reduced in corn flour spiked with 200mg/kg hydrolyzed wheat, rye, and barley flour. Thus, the gluten grain source and processing conditions should be considered for accurate gluten analysis.

Development of hypoimmunogenic muffins: batter rheology, quality characteristics, microstructure and immunochemical validation

A high demand exists for gluten free and hypoimmunogenic products from gluten sensitive population. The present study focuses on the development of hypoimmunogenic muffins using a combination of the blend (CB) consisting of modified (protease treated) Whole Wheat Flour (WWF) and Pearl Millet Flour (PMF). The batter density of CB was 0.97, and it varied between 0.91-0.93 and 0.97-0.99 g/cc with the use of emulsifiers and hydrocolloids respectively. The volume of the muffin made using CB was 70 mL, and it increased to 120 mL with the combination of additives (CAD) comprising of Carboxy Methyl Cellulose (CMC) and Polysorbate-60 (PS-60). The muffins made of CB + CAD had the lowest hardness (19.8 N) and gumminess (6.6 N) values and highest springiness value (13.3 mm) indicating that the texture was soft. Sensory characteristics of the muffin made with CB + CAD were good and had an overall quality score of 90.5 out of 100. Rheometer studies showed that the incorporation of additives improved the visco-elastic properties of muffin batters. Microstructure studies showed a change in gluten matrix of muffins followed by treatments. Immunochemical validation of muffins made using CB + CAD showed that the immunogenicity reduced by 70.8 % which may be suitable for patients with gluten sensitivity.

Effect of protein concentrates, emulsifiers on textural and sensory characteristics of gluten free cookies and its immunochemical validation

The effect of 5, 7.5 and 10 % protein concentrates namely soya protein isolate (SPI), whey protein concentrate (WPC) and addition of 0.5 % emulsifiers such as glycerol monostearate (GMS), sodium stearoyl- 2- lactylate (SSL) and lecithin (LEC) on the rheological, sensory and textural characteristics of cookies with rice flour and its immunochemical validation was studied. The results showed that the use of 7.5 % SPI/WPC along with GMS significantly improved the quality characteristics of cookies with rice flour. Dot-Blot and Western-blot studies of cookies with 7.5 % of SPI or WPC confirmed that the anti-gliadin did not recognize these proteins. Carry- through process using ELISA kit confirmed that gluten was within the permissible limit in all the stages of processing and hence these cookies can be consumed by people suffering from celiac disease.

A study on noodle dough rheology and product quality characteristics of fresh and dried noodles as influenced by low glycemic index ingredient

Low Glycemic Index (LGI) foods help to maintain blood glucose level in diabetic individuals. Pea flour (PF) is known to be one of LGI ingredients used in the food industry. To assess the influence of PF in noodle processing, thermally processed pea flour was incorporated at 20 % and 40 % in the preparation of noodles using Lab scale Noodle Making Machine. Evaluation for Physico-chemical, rheological and noodle making characteristics, in vitro starch digestibility (IVSD) and microstructure of noodles were carried out. Cooking quality did not show any significant difference among the samples, with solid leach out ranging from 6.7 to 7.2 % against control (6.5 %). Colour measurement showed the presence of greenish colour in PF incorporated samples. Texture was firmer in fresh noodles (FN) (5.52 Newton (N), 6.00 N) and dried noodles (DN) (7.60 N, 7.86 N) compared to control (4.38 N-FN, 6.88 N-DN). Sensory analysis of noodles revealed that the samples (FN, DN) were acceptable at 20 % and 40 % levels with overall quality score (>8.5). In vitro analysis revealed that with increase in PF content there was a significant decrease in the availability of glucose in DN followed by FN compared to control. Overall RDS was reduced and SDS was increased in 40 % PF incorporated FN. Scanning-electron microscopy revealed the presence of fiber matrix around the starch granules.