Gluten Fractions Research Articles

Control of wheat starch rheological properties and gel structure through modulating granule structure change by reconstituted gluten fractions

Reconstituted gluten fractions (RGF) varying in glutenin/gliadin (glu/gli) ratios was applied to change the property of wheat starch. The addition of RGF, irrespective of glu/gli ratio, significantly decreased the gelatinization enthalpy, viscosity, storage modulus (G'), and gel strength of starch. Starch particle size and leached amylose decreased by 4.5% and 22.2%, respectively, as the ratio of glu/gli changed from 1:0 to 0:1, indicating that the increase in gliadin ratio could inhibit swelling and rupturing of starch granules to a larger extent. Confocal laser scanning micrographs showed that gliadin could surround starch granules more effectively, thereby stabilizing the granule structure better than glutenin. With the increasing of gliadin ratio, the storage modulus (G′) and loss modulus (G″) of the starch paste declined, accompanied by more loose gel structure and weaker gel strength. By varying the ratios of glu/gli in RGF, the change of wheat starch granule structure could be modulated, and therefore the rheological properties and gel structure could be regulated.

Effect of extrusion on the modification of wheat flour proteins related to celiac disease.

Wheat flour was extruded using a single- and double-screw extruder at 130, 150, and 170°C, respectively, to determine the effect of extrusion on the content and possible modifications of protein in wheat flour. Regarding to proteins, their yield under non-reducing extraction conditions (in SDS only) decreased to one-third after extrusion-but remained constant after extraction under reduced conditions (in SDS + DTT). This phenomenon possibly reflected protein cross-linking through intermolecular disulfide bonds to gluten proteins, especially at high temperature and high screw speed during double-screw extrusion, as suggested by the increased number of free-SH-groups and reduced intensity of low-MW proteins in SDS-PAGE under this extrusion condition. Lysinoalanine was not detected in the extruded gluten fraction, indicating that non-disulfide bonds did not develop under the extrusion conditions. Furthermore, the reducing sugar content also decreased to > 50% only in all double-screw samples, indication Maillard reaction may contribute to protein modification during extrusion to some extent. Eventually, protein modification during extrusion may affect the celiac gluten toxicity of wheat gluten assessed by total gluten content and potential celiac toxicity.

The impact of gliadin and glutenin on the formation and structure of starch-lipid complexes

This study evaluated the influence of the main gluten fractions (gliadin and glutenin) on the physicochemical properties of binary wheat starch-Lauric acid (WS-LA) complexes during heat processing to explore the complex structure and digestion of WS-LA in the presence of gluten. Ternary WS-LA-glutenin complexes were prepared at different pH (5.2 and 7), whereas WS-LA-gliadin was prepared using ethanol, and their physicochemical properties were analyzed. We found that the addition of glutenin displayed a sharper and higher diffraction peak than samples without protein, which increased short-range order structure (low full width at half-maximum (FWHM) of the band at 480 cm−1) and good thermal stability (melting peak appeared at a higher temperature); the opposite was shown for gliadin. Even though glutenin increased the resistant starch (RS) content than WS-LA, all samples prepared in 65% ethanol showed higher RS content than WS-LA-glutenin samples. These findings might improve our understanding of the relationship between gliadin/glutenin and binary complexes and provide a theoretical basis for preparing starch-based foods with a low glycemic index.

Effect of Nitrogen Fertilization and Fungicide Application at Heading on the Gluten Protein Composition and Rheological Quality of Wheat

Optimizing the bread-making quality properties of flour is currently one of the main aims of the bakery industry. Therefore, this study has investigated the effects of N fertilization and fungicide application at wheat heading on the protein content (GPC), gluten composition and rheological properties of wheat. Field experiments were carried out in North-West Italy over a 3 year period, on a high protein cultivar of soft winter wheat. Grain samples were collected for each agronomic treatment at four ripening timings, from the milk stage to the final combine harvesting, and the contents of the different gluten fractions were quantified. The late N fertilization increased the GPC (+1.2%) and dough strength (W) (+22%) as a result of a similar enhancement of all the gluten protein fractions, while the fungicide application slightly reduced the GPC (−0.3%) and W (−4%), mainly because of a dilution of the gliadin content, due to the significantly higher grain yield (+8.6%) and thousand kernel weight (+5.5%). These agronomic practices did not modify the gluten composition significantly, expressed as the relative ratio between the gliadins (glia) and the high (HMW) and low (LMW) molecular weight glutenins (gs), and confirmed by the accumulation trend of the different protein fractions during ripening. The year resulted to have the most marked effect on the gluten protein fraction ratios and alveographic parameters. The lowest W was observed in 2015, and although the highest GPC was recorded for the same year, the lowest gs/glia ratio was also observed. Instead, 2016 showed the highest gs/glia and HMW-gs/LMW-gs (H/L) ratios, and also the highest P/L value (2.2). In 2015, a slightly higher temperature during the ripening stage resulted in a greater increase in the γ-gliadin enriched fraction than the α/β gliadin ones, and marked differences were noted in the rheological traits. This field experiment has highlighted the interactive role of environmental and agronomic factors on the content and quality of gluten proteins and their bread-making ability, thus making a further contribution to the development of an integrated crop strategy for the cultivation of high protein wheat in humid Mediterranean areas.

ВЛИЯНИЕ ФУНГИЦИДНОЙ ОБРАБОТКИ НА УРОЖАЙНОСТЬ И КАЧЕСТВО ЗЕРНА ОЗИМОЙ ПШЕНИЦЫ

In 2017-2019, studies were carried out in the Republic of Tatarstan to study the effect of fungicidal treatment on the yield and grain quality of new varieties of winter wheat. The experiment scheme provided for the study of the following options: variety (factor A) - Darina, Nadezhda, Universiade; fungicidal treatment with Titul Duo at a dose of 0.25 l / ha in the heading phase (factor B), years (factor C). The predecessor is pure steam. The soil in the experiment was gray forest, medium loamy. Content in the arable layer: humus (according to Tyurin) - 3.1-3.4%; pHsal. - 5.2-5.5; K2O (according to Kirsanov) - 122-145 mg / kg of soil, P2O5 (according to Kirsanov) - 262-271 mg / kg of soil. Plot area - 25 m2. The yield and quality of grain largely depend on the phytosanitary state of winter wheat crops, in particular, on the development of diseases. The prevalence and harmfulness of leaf-stem diseases in wheat largely depends on the temperature conditions during the growing season of the crop and on the moisture conditions. As a result of the development of diseases, there is a significant decrease not only in yield, but also a deterioration in the quality characteristics of wheat grain. The highest percentage of prevalence (85%) and intensity of development (45.7%) of powdery mildew was observed in the Universiade variety. Evaluation of plants showed a low lesion of the leaf surface by leaf rust: from 18.6% in the Nadezhda variety to 24.6% in the Universiade variety. The biological effectiveness of protective measures in winter wheat crops when treated with a fungicide has been calculated. On average for varieties for three years, the biological effectiveness of the use of the drug Title Duo was more than 90%. The fungicide treatment increased the yield on average for the studied varieties by 0.55 t / ha. The maximum increase in grain yield was obtained for the Universiade variety - 0.68 t / ha. Indicators of technological quality of grain with an average for varieties increased after treatment with fungicide sowing: weight of 1000 grains per 2.2 grams; grain nature by 5.4 g / l; glassiness by 2.6%; evenness by 1.4%; the wet gluten content is 1.6%. According to the results of analysis of variance, a significant influence of the conditions of the year on the indicators of the technological quality of grain was established: on the nature of the grain (56.8%), the total glassiness of the grain (51.43%), the mass of 1000 grains (51.4%) and the gluten deformation index (52.37%). To a lesser extent, environmental conditions influenced the evenness of the grain (22.0%) and the mass fraction of gluten in the grain (21.66%). At the same time, the contribution of the fungicide to the formation of indicators of the technological quality of grain varied from 7.69% (grain evenness) to 32.43% (gluten content). The grain nature by 14.99% was determined by the fungicidal treatment of crops and only by 10.61% depended on the genotype

Impacts of Celiac Disease and the Gluten-Free Diet on the Eating Habits and Quality of Life of Algerian Celiac Patients

Abstract Objectives Celiac disease is an autoimmune disease with manifestations at different levels. It is a disease developed in people with genetic susceptibility and intolerance to certain protein fractions of gluten, a protein found in all forms of wheat, rye and barley and causing villus atrophy. In Algeria, more than 500 000 people have celiac disease and the only treatment for celiac disease is to follow a strict, lifelong gluten-free diet, the objective of our work is to study the eating habits and gluten-free diet of 109 celiac patients residing in Algeria. Methods We carried out a cross-sectional survey using a questionnaire that has two sections: a section on eating habits, a section on frequencies of food consumption. Results Overall, we found that 67.9% of patients strictly followed their diet which led to difficulty in eating out of home and the need to take food while traveling. The difficulties in purchasing gluten-free foods were also mentioned by most patients. In addition, the gluten-free diet interfered with the patients' ability to work and with their social activities. Regarding the diet of our patients, the main foods consumed were vegetables, fruits, pulses, rice, pancakes, eggs, chicken meat and milk. Conclusions The negative effects of celiac disease and the gluten-free diet on patients can be minimized by better patient management, especially by joining associations. Funding Sources The Institute of Nutrition, Food and Agri-Food Technologies, Hospital-University Center CONSTANTINE Benbadis polyclinic el arbi ben mhidi, Polyclinic Filali, Constantine SIDI MABROUK PIDIATRIC EHS Constantine Hospitals.

Evaluation of consumer properties of grain of spring soft wheat selection lines

The article presents the results of studying 10 numbers of competitive variety testing in the Ryazan region in order to identify new breeding lines of spring soft wheat with high technological and baking indicators. The assessment carried out in 2017-2019 revealed that according to the yield the breeding lines 1036-09Н21 and 898-09Н125 exceeded the Agata standard variety (4.47 t/ha) by 0.61 t/ha and 0.48 t ha, respectively (LSD05 = 0.34 t/ha). Over the years of the research, the variety samples formed a glassy well-made grain with the nature of 770-817 g/l, with the protein content in the grain of 14.1-16.0 % and the mass fraction of raw gluten in the flour of 29-41 % of high quality (IDK 45-75 units). The greatest potential for protein accumulation in grain was possessed by the varieties Agata, RIMA, lines 539-10H163, 543-13H163 – 16.8-19.3 %. On the average, the falling number was relatively high 264-331 s, corresponding for wheat of the first and second classes. Lines 543-13H163, 539-10H163 and 898-09H125 exceeded the standard in terms of sedimentation value by 15-17 ml or 35-40 %. The specific work of the dough deformation in the samples varied from 305 a.u. up to 421 a.u., corresponding to the standards of strong or valuable wheat. It has been established that the volumetric yield of bread for lines 509-13Н148, 539-10Н163 and 543-13Н163 was 1633-1647 cm3, higher than the Agat standard variety by 16-17 %. Valuable material 539-10N163 and 898-09N125 that meets the requirements of flour-grinding and bakery enterprises has been developed. It has the following varietal characteristics: grain nature is more than 800 g/l, protein content in grain is 15-16 %, gluten in flour is 33-34 %, with the sedimentation indicator of 58-60 ml, the deformation energy of the dough of 389-421 a.u, the volumetric bread yield of 1523-1647 cm3.

Gluten aggregation properties as a tool for durum wheat quality assessment: A chemometric approach

The study aims at assessing the gluten aggregation properties of wholemeal semolina for the differentiation of durum wheat cultivars with different amounts of gluten-quality related fractions. To this end, a calibration set of 56 durum wheat cultivars harvested in 2015–2016 was categorized into four quality classes based on the total gluten protein content and the glutenin to gliadin ratio. Quality class distribution was carried out by Principal Component Analysis (PCA) performed on either gluten aggregation parameters alone or with gluten fractions. PCA differentiated high and medium-high quality varieties from those of low and medium-low quality. Furthermore, PCA confirmed the relationship between gluten fractions and their aggregation kinetics, by means of a validation step consisting of 22 cultivars harvested in 2016–2017. In conclusion, gluten aggregation properties proved to be good indicators of durum wheat semolina quality, and thus a reliable tool for blend preparation in the pasta-making process.

Development of a concept for the production of wheat snacks with the elimination of gluten by the biocatalysis

The increase in the number of cases of allergic reactions and celiac disease is an important problem. The solution to this problem is the search and development of relevant and effective ways to eliminate gluten. Specific amino acid sequences glutamine and proline determine the resistance to protease hydrolysis of the structural domains of gluten fractions. The analysis of the literature data showed that an alternative to the gluten-free diet is the use of biotechnological methods for modifying ingredients containing gluten. Such methods include the use of leavens on the base of lactic acid bacteria or enzyme preparations containing peptidases specific to gluten biocatalysis. In addition, the pretreatment of raw materials by extrusion cooking contributes to an increase in the degree of gluten hydrolysis. The effect of the thermoplastic extrusion and various enzyme systems containing proteases, amylolytic, cellulolytic and hemicellulolytic enzymes on the changes in the molecular weights of wheat protein fractions was studied. It was found that extrusion as a factor of protein modification significantly affects the proteolysis of wheat proteins using enzyme systems of different substrate specificity. The most effective hydrolysis was shown by the use of a complex enzyme preparation Amyloprotoorizin. including The effect was also noted after bioconversion of non-extruded wheat. An algorithm for the technology of wheat snacks based on the processes of extrusion and biocatalysis of proteins with specific proteases for the elimination of gluten is devepoped. The practical implementation of the technology will make it possible to obtain ready-to-eat snacks, which will be investigated for the preservation or elimination of antigenic properties during clinical trials.

Влияние способов и доз внесения удобрений на продуктивность озимой пшеницы при прямом посеве на черноземе обыкновенном

Purpose: to study the influence of methods and rates of mineral fertilizers on the winter wheat yield and grain quality by direct sowing on corn on ordinary chernozem under conditions of unstable moisture in Stavropol Territory. Materials and methods. The studies were carried out in 2014–2019 in a three-factor experiment in the fields of the North Caucasus Federal Scientific Agrarian Center. We studied the effect of pre-sowing fertilization and nitrogen fertilization (N52) on wheat productivity with two tillage technologies: with the recommended tillage system and with direct sowing (No-Till). Pre-sowing fertilization options: 1) without fertilizers; 2) N6P26; 3) N12P52; 4) N24P104; 5) N52P52; 6) N52P52K52; 7) N52; 8) N104P52K52. Results. Direct sowing had an advantage over the recommended technology in the reserves of productive moisture in the soil layer of 0–100 cm during the sowing period. In the No-Till technology, the average yield increase from pre-sowing fertilizer was within 0.78–3.02 t/ha (28–109 %), from nitrogen fertilization it was 0.55–1.85 t/ha (15–48 %) and when both methods of application are combined – 1.47–4.02 t/ha (53–145 %). The highest and most stable increments over the years (3.07–4.56 t/ha, or 101–219 % to the control) were obtained when using the maximum rate of pre-sowing fertilizer with nitrogen fertilization – N104P52K52 + N52. The increase in grain yield per unit of active fertilizer substance was 15.5 kg. Mass fraction of crude gluten in grain exceeded the control by 3.0–7.9 %. The application of this fertilizer dose helped to equalize the yield between technologies. Conclusions. The results showed that in order to obtain the greatest agronomic effect in the third year of direct sowing of winter wheat on maize, the predominant application of nitrogen fertilizer in a total dose exceeding the dose of phosphorus and potassium by 2–3 times is required. Correctly selected methods of application and fertilizers rates prevent a decrease in wheat yield when switching from the recommended tillage technology to direct sowing.

Improvement of the technology of bakery products using the wholemeal spelt flour

Bread is one of the most popular mass-consumption products in Russia and in the world. The improvement of the bread quality, the development of new varieties with increased nutritional and biological value will improve the nutrition patterns of the population in the most rational way. The objective of this study is to justify the use of wholemeal spelt flour in the formulation of wheat bread. Generally accepted standard research methods were used. It is experimentally proved that the addition of spelt flour to the flour blend increases the activity of amylolytic enzymes, as well as decreases the mass fraction of crude gluten in all dough samples. When adding the spelt flour in the proportion 40% of the flour weight, physical and chemical parameters did not deteriorate and fell within the normal range, compared with the control sample of wheat bread. It is proved that the use of spelt flour in the production of bakery products will increase the biological and nutritional value of products, as well as expand the range of products for healthy nutrition.

Određivanje različitih uslova ekstrakcije na efikasnost ekstrakcije i određivanje glijadina ELISA metodom

Gluten refers to a complex mixture of gliadins and glutenins. It can cause numerous foodborne disorders. In sensitive individuals gluten can lead to celiac disease (CD), wheat sensitivity and allergy. Gliadin proteins are one of the gluten fractions. The aim of this paper was to examine how different conditions, mixing time (2.5, 5, 7.5, and 10 min) of the sample with the most commonly solvent 70% (v/v) ethanol and 70% (v/v) isopropanol and incubation time (15, 20, 25, and 30 min) affect the efficiency of gliadin determination with the ELISA method. A commercial kit was used to determine gliadin concentrations, and absorbance was measured at 450 nm, using the ELISA reader. Based on the obtained results, the optimal mixing time of the sample with the solvents was 5 minutes and the incubation time was 25 minutes. Under these conditions, the extraction efficiency is the best, i.e., the highest gliadin concentration is obtained. The results of research can be of fundamental importance in the study of gluten proteins and the impact of technological procedures on their change and the possibility of reducing the allergic effect.

Durum Wheat Grain Yield and Quality under Low and High Nitrogen Conditions: Insights into Natural Variation in Low- and High-Yielding Genotypes.

The availability and management of N are major determinants of crop productivity, but N excessive use has an associated agro-ecosystems environmental impact. The aim of this work was to investigate the influence of N fertilization on yield and grain quality of 6 durum wheat genotypes, selected from 20 genotypes as high- and low-yielding genotypes. Two N levels were applied from anthesis to maturity: high (½ Hoagland nutrient solution) and low (modified ½ Hoagland with one-third of N). Together with the agronomic characterization, grain quality analyses were assessed to characterize carbohydrates concentration, mineral composition, glutenin and gliadin concentrations, polyphenol profile, and anti-radical activity. Nitrogen supply improved wheat grain yield with no effect on thousand-grain weight. Grain soluble sugars and gluten fractions were increased, but starch concentration was reduced, under high N. Mineral composition and polyphenol concentrations were also improved by N application. High-yielding genotypes had higher grain carbohydrates concentrations, while higher concentrations in grain minerals, gluten fractions, and polyphenols were recorded in the low-yielding ones. Decreasing the amount of N to one-third ensured a better N use efficiency but reduced durum wheat agronomic and quality traits.

N Partitioning between Gluten Fractions in a Set of Italian Durum Wheat Cultivars: Role of the Grain N Content.

Grain protein content constitutes a key quality trait for durum wheat end-products and may also impact grain protein composition. A total of sixteen durum wheat cultivars were analyzed in a field trial during two seasons at two nitrogen (N) levels to evaluate whether and to what extent the variation in total grain N was associated with variation in the quantity of the various protein fractions and grain quality parameters. Genotypic variation in grain N content correlated with the variation in the content of all three protein fractions, although the strength of the correlation with gliadin and albumin-globulin was higher than that with glutenins. Genotypic variation in gliadin and glutenin content was more tightly correlated with the variation in the sulfur (S)-rich protein groups than with the S-poor protein groups and subunits. The variation in the percentage of unextractable polymeric proteins (UPP%) among genotypes was independent of their glutenin allelic composition. The significant genotypic differences in UPP% and in the ratios between protein groups and subunits were not influenced by the corresponding variation in grain N content. The final grain N content can only account for part of the variation in quality parameters and in the partitioning of total grain N between protein fractions since genotypic differences other than grain N content also contribute to these variations.

GLUTOMATİK 4+2 SİSTEMİ İLE GLUTEN İNDEKS PARAMETRESİNE YENİ BİR BAKIŞ

Buğday ve unlardaki toplam protein içindeki gluten fraksiyonu esas olarak hamurun reolojik ve teknolojik özelliklerinden sorumlu olup üzerinde çok geniş araştırmalar yapılmıştır. Glutenin elle ya da yarı otomatik aletler yardımıyla analizine yönelik uluslararası standartlar geliştirilmiş ve 1988 yılında elde edilen glutenin santrifüj kuvvetine tabi tutulmasıyla elekte kalan yaş özün ağırlık olarak yüzdesini ifaden gluten indeks değeri kalitenin belirlenmesinde önemli bir veri oluşturmuştur. Bu derlemenin amacı; glutenin nitel ve nicelik olarak kalitesini bir bütün olarak ele almak ve aynı zamanda Glutomatik Sisteminde 20 saniyelik standart yoğurma süresi uzatılarak 40 ve 60 saniye süre uygulaması olarak tanımlanan Glutomatik 4+2 sistemi ile gluten kalitesindeki değişimleri farklı un çeşitleri için elde edilen Gluten Performans Grafikleri ile yorumlanmasını açıklamaktır.

Separation of gliadins from wheat flour by capillary gel electrophoresis: optimal conditions

Introduction. Gliadin proteins are one of the gluten fractions. They are soluble in alcoholic solution and divided into four groups (α + β, γ, ω1.2, and ω5-gliadins). In this paper gliadins were extracted from wheat flour, and optimal conditions for their separation were determined.
 Study objects and methods. The separation was performed by capillary gel electrophoresis on Agilent apparatus, CE 7100 (a capillary with an inner diameter of 50 μm, a total length of 33 cm, and an effective length of 23.50 cm). In order to determine the optimal conditions, different solvent concentrations (50, 60, and 70% ethanol), capillary temperatures (20, 25, 30, 35, and 40°C), and electrode voltages (–14.5, –16.5, –17.5 and –18.5 kV) were applied. Migration time and relative concentration of each protein molecules within gliadin fractions in the electrophoregram were analysed using Agilent ChemStation Software.
 Results and discussion. The optimal conditions for gliadin separation were: solvent 70% (v/v) ethanol, capillary temperature of 25°C, and electrode voltage of –16.5 kV. Under these conditions, the total proteins were indetified as Xav = 23.50, including α + β gliadin fraction (Xav = 7.50 and relative concentration RC = 28.29%), γ-gliadins (Xav = 5.00, RC = 26.66%), ω1.2-gliadins (Xav = 4.33, RC = 14.93%), and ω5-gliadins (Xav = 6.67, RC = 30.98%).
 Conclusion. The results of the research can be of fundamental importance in the study of gluten proteins and the influence of technological procedures on their change and the possibility of reducing the allergic effect of gluten during processing.

Characterization of Celiac Disease-Related Epitopes and Gluten Fractions, and Identification of Associated Loci in Durum Wheat

While durum wheat is a major food source in Mediterranean countries, storage (i.e., gluten) proteins are however responsible for celiac disease (CD), a serious autoimmune disease that occurs in genetically predisposed subjects. Different gluten epitopes—defined as “immunogenic” (IP) and “toxic” (TP) peptides—are involved in the pathology and their content in wheat grain depends on environmental and genetic factors. Detection of IP and TP is not trivial, and no work has been conducted so far to identify the genomic regions associated with their accumulation in wheat. In the present study, a genome-wide association study was performed on a durum wheat collection to identify marker–trait associations (MTAs) between 5730 high quality SNPs and the accumulation of CD-related peptides and gluten protein composition measured in two consecutive cropping seasons (2015/2016 and 2016/2017). High-molecular-weight glutenin subunits (HMW-GS) were more stable between the two years, and differences in total gluten proteins were mainly due to low-molecular-weight glutenin subunits (LMW-GS) and accumulation of gliadins. In the first instance, association tests were conducted on yellow pigment content (YP), a highly inheritable trait with a well-known genetic basis, and several significant MTAs were found corresponding to loci already known for being related to YP. These findings showed that MTAs found for the rest of the measured traits were reliable. In total, 28 significant MTAs were found for gluten composition, while 14 were found to be associated with IP and TP. Noteworthy, neither significant (−log10p > 4.7) nor suggestive (−log10p > 3.3) MTAs for the accumulation of CD-triggering epitopes were found on Gli-A1/Glu-A3 and Gli-B1/Glu-B3 loci, thus suggesting regulatory rather than structural gene effect. A PBF transcription factor on chromosome 5B, known to be involved in the regulation of the expression of CD-related peptides, was identified among the positional candidate genes in the LD-decay range around significant SNPs. Results obtained in the present study provide useful insights and resources for the long-term objective of selecting low-toxic durum wheat varieties while maintaining satisfactory gluten quality.

X6: A Novel Antibody for Potential Use in Gluten Quantification.

Gliadin is a fraction of gluten, known to trigger celiac disease in susceptible people. To date, the life-long gluten-free diet is used for the prevention of this disease. Hence, methods for gluten control in foods are of significant importance. Being one of the most-used methods used for this purpose, ELISA should use high-affinity antibodies to gliadin peptides involved into celiac process. This study investigates the characteristics of a novel anti-gliadin antibody X6. We found the QXQPFPXP site to be a recognized epitope that provides specific binding of the antibody to cereal prolamins involved in celiac disease manifestation. A specificity study using immunoblotting shows the recognition of wheat, barley and rye proteins—as well as α-gliadin homologs from non-edible cereals (Dasypyrum villosum). Reactivity to avenin was less pronounced, as this protein does not contain the PFP motif most critical for antibody recognition. The proteins of Zea mays and Setaria italica were not recognized by X6. X6-based ELISA highly correlated with R5 and G12, which are Codex Alimentarius standards in the quantitative assessment of gluten content (Pearson’s R = 0.86 and 0.87, respectively). Qualitative assessment revealed no significant differences between R5 and G12 and X6.

Исследование влияния температурных режимов хранения на показатели сохранности и технологические показатели пшеницы

При хранении на элеваторах и складах зерно подвергается воздействию температур, связанных с сезонными колебаниями. Температурный режим влияет на старение зерна за счет изменений углеводного и белково-липидного комплексов, процессов дыхания, влагосорбционных изменений, а также развития вредителей. В статье приведены результаты изменения качества зерна мягкой пшеницы при разных температурах хранения. Показано, что интенсивность изменения отдельных показателей качества пшеницы зависит от температурных условий хранения: при температурах 30 и 40°С отмечены наиболее существенные изменения показателей качества: снижение массовой доли клейковины, снижение стекловидности, увеличение числа падения и увеличение кислотного числа жира. Регрессионный анализ полученных данных позволил установить зависимость показателей качества от температуры хранения. Наиболее благоприятным температурным режимом определена температура 10°С, при которой качество пшеницы по нормируемым показателям характеризуется значениями на уровне исходного зерна. Выполненные эксперименты актуальны для обоснования оптимальных режимов в практике длительного хранения зерна, а также для составления прогнозных значений по срокам его хранения.

Safety evaluation of the food enzyme endo-1,4-β-xylanase from the genetically modified Trichoderma reesei strain RF5427.

The food enzyme endo‐1,4‐β‐xylanase (4‐β‐D‐xylan xylanohydrolase; EC 3.2.1.8) is produced with the genetically modified Trichoderma reesei strain RF5427 by AB Enzymes GmbH. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and recombinant DNA. It is intended to be used in baking, brewing and cereal‐based processes, distilled alcohol production and grain treatment for the production of starch and gluten fractions. Since residual amounts of the food enzyme are removed by distillation and during grain treatment, dietary exposure was only calculated for baking, brewing and cereal‐based processes. Based on the proposed maximum use levels, dietary exposure to the food enzyme–Total Organic Solids (TOS) was estimated to be up to 0.119 mg TOS/kg body weight (bw) per day. Genotoxicity tests did not raise a safety concern. The Panel identified a no observed adverse effect level at the highest dose tested of 939 mg TOS/kg bw per day in a repeated dose 90‐day oral toxicity study in rats, resulting in a margin of exposure of at least 7,890. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and no matches were found. The Panel considered that allergenicity can be excluded for distilled alcohol production. The risk of allergic sensitisation and elicitation reactions cannot be excluded for baking, brewing and cereal‐based processes, and for grain treatment for the production of starch and gluten fractions, but the likelihood of such reactions to occur is considered to be low. Based on the data provided, the removal of TOS during the production of distilled alcohol and grain treatment, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.