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Einkorn Characterization for Bread and Cookie Production in Relation to Protein Subunit Composition

by luciano

The research showed, through tests to make bread and biscuits, the best varieties of monococcum wheat among the 24 examined: among these the varieties ID140, ID280 and Id361 were the best for both uses. The research also shows how, due to the rheological properties of the flours, the presence or absence of a very limited number of storage protein subunits is important, highlighting the importance of LMW

Einkorn Characterization for Bread and Cookie Production in Relation to Protein Subunit Composition M. Corbellini, S. Empilli, P. Vaccino, A. Brandolini, B. Borghi, M. Heun, and F. Salamini. Cereal Chem. 76(5):727–733
Abstract
“Twenty-four einkorns were evaluated for agronomic traits in Italy and in Germany in replicated plot trials. After dehulling and milling, the harvested kernels, flour protein content, sedimentation volume, falling number, carotenoid, and dry gluten content were determined. Farinograph profiles were obtained with a farinograph and baking and cookie quality were evaluated with standard microtests. Significant differences in yield potential were observed between the two locations, with a three-fold increase in Germany as compared with Italy. One of the einkorn lines (ID529) had farinograph stability and degree of softening indices better than those of the control bread wheat. All the samples analyzed for breadmaking aptitude showed some degree of stickiness, but it was possible to handle the dough during the different steps of breadmaking. On average, cookies produced with einkorn flour were larger in diameter and thinner than those produced with soft wheat flour. The composition in α, β and γ-gliadins and in high molecular weight glutenin subunits was similar in all the lines. In contrast, the pattern exhibited in low molecular weight glutenin subunits correlated strictly with baking quality. In particular, the lines with bands arbitrarily designated a and b showed a high breadmaking poten- tial, while the lines lacking these bands had an ample range of variability but, on average, a much lower baking potential. Our data point to a simple genetic control of the breadmaking aptitude and indicate einkorn not only as a promising source of specialty foods but also as an ideal species for genetic investigations on wheat quality”.

NOTE:
LMW-GS: Low Molecular Weight – Glutenin Subunit

(Table extracted from the research)

Electrophoretic characterization of reserve proteins: glutenins and gliadins. They represent, with the different respective bands, the genetic imprint that defines and identifies the variety. (Table extracted from the research)

Monococcum wheat (einkorn) and wheat allergy

by luciano

The research reported in the summary highlighted the absence of ω-5 gliadin in the monococcum wheat responsible for wheat allergy: another important characteristic of the monococcum wheat!

Study on the Immunoreactivity of Triticum monococcum (Einkorn) Wheat in Patients with Wheat-Dependent Exercise-Induced Anaphylaxis for the Production of Hypoallergenic Foods. Carla Lombardo, Michela Bolla Roberto Chignola Gianenrico Senna Giacomo Rossin Beatrice Caruso, Carlo Tomelleri Daniela Cecconi Andrea Brandolini Gianni Zoccatelli. Cite This:J. Agric. Food Chem.201563378299-8306. Publication Date:September 2, 2015. https://doi.org/10.1021/acs.jafc.5b02648 Copyright © 2015 American Chemical Society Journal of Agricultural and Food Chemistry
Abstract
“Wheat [Triticum aestivum (T.a.)] ingestion can cause a specific allergic reaction, which is called wheat-dependent exercise-induced anaphylaxis (WDEIA). The major allergen involved is ω-5 gliadin, a gluten protein coded by genes located on the B genome. Our aim was to study the immunoreactivity of proteins in Triticum monococcum (einkorn, T.m.), a diploid ancestral wheat lacking B chromosomes, for possible use in the production of hypoallergenic foods. A total of 14 patients with a clear history of WDEIA and specific immunoglobulin E (IgE) to ω-5 gliadin were enrolled. Skin prick test (SPT) with a commercial wheat extract and an in-house T.a. gluten diagnostic solution tested positive for 43 and 100% of the cases, respectively. No reactivity in patients tested with solutions prepared from four T.m. accessions was observed. The immunoblotting of T.m. gluten proteins performed with the sera of patients showed different IgE-binding profiles with respect to T.a., confirming the absence of ω-5 gliadin. A general lower immunoreactivity of T.m. gluten proteins with scarce cross-reactivity to ω-5 gliadin epitopes was assessed by an enzyme-linked immunosorbent assay (ELISA). Given the absence of reactivity by SPT and the limited cross-reactivity with ω-5 gliadin, T.m. might represent a potential candidate in the production of hypoallergenic bakery products for patients sensitized to ω-5 gliadin. Further analyses need to be carried out regarding its safety”.

Simultaneously identify the gluten peptides that are most active in activating the human immune system

by luciano

The method aims to identify, through the use of specific antibodies, the most toxic peptides instead of, as with the usual methods used today, the total gluten content. Considering that the research is also focused on producing grains with smaller amounts of toxic peptides, as well as using specific pools of enzymes / bacteria / etc in the preparation of products with the same purpose, the possibility of identifying and “weighing” only the presence, in the final product, more active peptides become a very useful tool. The highlighted study traces the history of the methods used to quantify gluten in food and presents advantages and limitations of the new method. All the methods mentioned, including the new method, have been developed to be able to certify whether a food is safe for celiacs or not, but the new methods become even more interesting for non-celiac and / or pre-celiac gluten sensitive subjects. The toxic fraction harmful to celiacs is the same as in people who are sensitive to gluten NOT celiac (1) but has a very different and less harmful impact: the new method is, therefore, very useful also in this case with the advantage of being able to have a greater tolerance in the result.

NEW IMMUNOCHEMICAL DETECTION METHODS

“Techniques that allow for the simultaneous detection of multiple different peptides are avail able, and are making their way into the field of food allergen detection. Another interesting possibility in gluten detection with the use of a multiplex immunoassay is to narrow down the focus even further to the harmful gluten epitopes. If antibodies were raised against the most relevant gluten epitopes, the detection of these specific epitopes could prove more relevant than detecting the total gluten content. A multiplex immunoassay can be updated by adding antibodies against more epitopes, and therefore can keep up with our increasing knowledge on harmful gluten epitopes. Also, by combining antibodies against the most relevant epitopes in a single detection method, the possibility of a false negative result decreases. Van den Broeck et al have investigated the possibilities of breeding a wheat variety with reduced CD-epitopes, based on small varieties in amino acid sequences between different gluten peptides (van den Broeck et al., 2011). If such a wheat variety could be bred, quantifying the total gluten content of food products containing this variety would be less appropriate. However, a detection method that can detect the presence of the harmful epitopes in these products would be very welcome. If the obstacles for developing a multiplex immunoassay can be overcome, this detection method would help providing consumers with more accurate food labels. This would further improve both food safety and the variety of choice in food products for CD patients everywhere”.

Depeening

Immunochemical Detection Methods for Gluten in Food Products: Where Do We Go from Here?

Note:

(1) – Gluten Immunogenic Peptides as Standard for the Evaluation of Potential Harmful Prolamin Content in Food and Human Specimen.

Ángel Cebolla , María de Lourdes Moreno , Laura Coto and Carolina Sousa

Published: 5 December 2018

 

 

Einkorn, emmer and durum wheat

by luciano

Einkorn, emmer and durum wheat: they do not have the “33mer” fraction considered the most active in activating the adverse response of the immune system in celiac subjects. Also for this reason they are the most suitable genotypes for the researches whose aim is to “detoxify” the flours or to intervene with particular enzymes to hydrolyse the “toxic peptides”, however present; they are also more suitable for non-celiac gluten sensitive subjects.

“Quantitation of the immunodominant 33-mer peptide from α-gliadin in wheat flours by liquid chromatography tandem mass spectrometry.

Kathrin Schalk , Christina Lang , Herbert Wieser , Peter Koehler  & Katharina Anne Scherf. Scientific Reports volume 7, Article number: 45092 (2017)

Abstract

Coeliac disease (CD) is triggered by the ingestion of gluten proteins from wheat, rye, and barley. The 33-mer peptide from α2-gliadin has frequently been described as the most important CD-immunogenic sequence within gluten. However, from more than 890 published amino acid sequences of α-gliadins, only 19 sequences contain the 33-mer. In order to make a precise assessment of the importance of the 33-mer, it is necessary to elucidate which wheat species and cultivars contain the peptide and at which concentrations. This paper presents the development of a stable isotope dilution assay followed by liquid chromatography tandem mass spectrometry to quantitate the 33-mer in flours of 23 hexaploid modern and 15 old common (bread) wheat as well as two spelt cultivars. All flours contained the 33-mer peptide at levels ranging from 91–603 μg/g flour. In contrast, the 33-mer was absent (<limit of detection) from tetra- and diploid species (durum wheat, emmer, einkorn), most likely because of the absence of the D-genome, which encodes α2-gliadins. Due to the presence of the 33-mer in all common wheat and spelt flours analysed here, the special focus in the literature on this most immunodominant peptide seems to be justified……Omissis…..

Analysis of durum wheat, emmer and einkorn

The 33-mer peptide was also analysed in two durum wheat and two emmer cultivars (genome AABB) as well as two diploid einkorn cultivars (genome AA) (Table 1). In each of these wheat species, the 33-mer was not detected (<LOD). In comparison to hexaploid common wheat, durum wheat, emmer, and einkorn do not contain the D-genome, which originated from hybridisation of T. turgidum dicoccum (genome AABB) with Aegilops tauschii (genome DD)36. The absence of the 33-mer peptide can be explained by the fact that this peptide is encoded by genes located in the Gli-2 locus on chromosome 6D, which is missing in durum wheat, emmer, and einkorn. Studies by Molberg et al. showed clear variations in intestinal T-cell responses between common wheat and tetra- or diploid species due to different degrees of T-cell immunoreactivity between the gluten proteins encoded on the A-, B-, and D-genome. Einkorn cultivars were only recognized by DQ2.5-glia-α1a-specific T-cell clones, but not by DQ2.5-glia-α1b- and DQ2.5-glia-α2-specific T-cell clones. Emmer and durum wheat cultivars were all recognized by DQ2.5-glia-α1a-specific T-cell clones, but only two out of four emmer cultivars and three out of ten durum wheat cultivars activated DQ2.5-glia-α1b- and DQ2.5-glia-α2-specific T-cell clones37. Consistent with our results, Prandi et al.38 found that the 33-mer was not present in durum wheat. As a consequence, this peptide was used as a marker peptide to identify the presence of common wheat in durum wheat flours. One durum wheat cultivar was also analysed by van den Broeck et al.33 and the 33-mer peptide was not detected either”. https://creativecommons.org/licenses/by/4.0/deed.it