Ivana Capouchová

Effects of milling and baking technologies on levels of deoxynivalenol and its masked form deoxynivalenol-3-glucoside.

The co-occurrence of the major Fusarium mycotoxin deoxynivalenol (DON) and its conjugate deoxynivalenol-3-glucoside (DON-3-Glc) has been documented in infected wheat. This study reports on the fate of this masked DON within milling and baking technologies for the first time and compares its levels with those of the free parent toxin. The fractionation of DON-3-Glc and DON in milling fractions was similar, tested white flours contained only approximately 60% of their content in unprocessed wheat grains. No substantial changes of both target analytes occurred during the dough preparation process, i.e. kneading, fermentation, and proofing. However, when bakery improvers enzymes mixtures were employed as a dough ingredient, a distinct increase up to 145% of conjugated DON-3-Glc occurred in fermented dough. Some decrease of both DON-3-Glc and DON (10 and 13%, respectively, compared to fermented dough) took place during baking. Thermal degradation products of DON, namely norDON A, B, C, D, and DON-lactone were detected in roasted wheat samples and baked bread samples by means of UPLC-Orbitrap MS. Moreover, thermal degradation products derived from DON-3-Glc were detected and tentatively identified in heat-treated contaminated wheat and bread based on accurate mass measurement performed under the ultrahigh mass resolving power. These products, originating from DON-3-Glc through de-epoxidation and other structural changes in the seskviterpene cycle, were named norDON-3-Glc A, B, C, D, and DON-3-Glc-lactone analogically to DON degradation products. Most of these compounds were located in the crust of experimental breads.

Agronomic characteristics of the spring forms of the wheat landraces (einkorn, emmer, spelt, intermediate bread wheat) grown in organic farming.

Agronomic characteristics of the spring forms of the wheat landraces (einkorn, emmer, spelt, intermediate bread wheat) grown in organic farming Organic farmers look to the possibilities of growing neglected crops, such as the spring forms of hulled wheat - einkorn, emmer and spelt - for support in developing the organic farming system. In 2008, 169 landraces from the gene bank at the Crop Research Institute in Prague were tested on certified organic plots. The experiment was aimed at finding suitable varieties for the organic farming system. In summary, our findings show that einkorn (Triticum monococcum L.) and emmer wheat [Triticum dicoccum Schrank (Schuebl)] are resistant to powdery mildew and brown rust, spelt wheat (Triticum spelta L.) is less resistant to these two diseases, and the intermediate forms of bread wheat are very sensitive to such infestation. The varieties evaluated incline to lodging, as they have long and weak stems. Einkorn and emmer wheat have short and dense spikes and a low thousand grains weight, whereas spelt wheat has long and lax spikes. The level of the harvest index is low. Potentially useful varieties were found during the field experiment and evaluation, and our future efforts will therefore focus on improving resistance to lodging and increasing the productivity of the spike.

Ancient wheat species can extend biodiversity of cultivated crops

Wheat genetic resources may be grown in organic farming systems or in less favourable areas for bread wheat species. Characteristics of hulled wheat species (23 varieties of einkorn, emmer wheat, spelt wheat) were studied and evaluated within a two-year trial period (which was executed on certified organic fields) and they were compared to characteristics of landraces and modern bread wheat varieties. The main aim of our study was to evaluate the potential uses of genetic resources of wheat in organic farming. The hulled wheat species were resistant to mildew and brown rust. Their grains were less contaminated with DON than the grains of the control varieties. The grain yield rate was reduced. Per hectare crude protein yield was higher in spelt and emmer wheat species than in the control varieties. High protein proportion in grain was an important advantage of the hulled wheat species. Spelt wheat is suitable for production of products similar to bread wheat (they have similar technological qualities). Einkorn and emmer wheat contain worse-quality gluten and therefore are suitable for the production of unyeasty products, that is pasta, mush, traditional unyeasty bread, etc.

Changes in the content of various Fusarium mycotoxins forms in germinating winter wheat and spring barley kernels

Fusarium mycotoxins are frequent contaminants in cereals at temperate zone. Next to deoxynivalenol (DON), there are other masked forms of DON, deoxynivalenol-3-glucoside (D3G) or 3(15)-acetyl-deoxynivalenol (3(15)-ADON), but changes among these forms are still insufficiently known. All these forms were evaluated in germinating kernels of wheat and malting barley from deliberated inoculated field plots. Results showed possible occurrence of high ini tial content of all evaluated DON forms. Total contents of all forms were detected as very steady from start to end of the germination process. It suggests high importance of evaluating not only DON content, but all DON forms simultaneously.

Diversity of carbon isotope discrimination in genetic resources of wheat

Strong drought tolerance is an important objective in breeding new wheat varieties. We compared the drought tolerance of land races and modern varieties of various spring wheat forms. 13C discrimination (CID) indicated how significantly the tested wheat varieties were inclined to drought tolerance. CID is a trait related to stomatal closure and consequently an important component of the tolerance to drought. Samples were grown in Ceske Budĕjovice (CZ), from 2009 to 2012. Twenty-three varieties, comprising einkorn, emmer, spelt, land races and control variety of bread wheat were grown and tested. Results have shown some varieties achieved low CID values (which meant they were more inclined to the drought tolerance). There were emmer and spelt varieties among them in particular. The spelt varieties which were inclined to the drought tolerance most significantly were — Triticum spelta No. 8930, Tabor 23 and Tabor 22. The emmer varieties called May-Emmer and Weisser Sommer were also inclined to drought tolera...

Drought Tolerance of Different Wheat Species (Triticum L.)

Water deficiency is one of the factors limiting the efficiency wheat growing all over the world. In the context of global climate changes, a question of the tolerance to drought has become more important in regions where this aspect was never taken into account before in the breeding process. Our paper presents a comparison of various wheat landraces (einkorn, emmer, spelt) and bread wheat varieties. It is based on the results of δ13C, chlorophyll content and quantity of stomata. The research was carried out in a greenhouse in different soil humidity (10 and 20 %). The results of our research have shown a relation between low values of δ13C, high proportion of chlorophyll and low quantity of pores (the predisposition to the tolerance to drought). In general, einkorn varieties, emmer and spelt wheat varieties have been the most predisposed to the tolerance to drought. On the other hand, intermediate wheat forms and modern bread wheat varieties have been supposed to be less tolerant to drought. The emmer wheat variety Rudico has become the most prospective variety of all (δ13C = −26.93 ‰; proportion of chlorophyll = 1.55 mg/dm; quantity of pores = 21.67 per square mm).

Rheological and Technological Quality of Minor Wheat Species and Common Wheat

Wheat is an important food grain source that nurtures millions of people around the world. Not only does wheat contain a large number of nutrients such as protein, wet gluten, etc., but also it has a lot of antioxidants such as dietary fibre, tocopherols, tocotrienols, etc. In a majority of cases, attention has been drawn to evaluate the grain yield and its components rather than its quality. The present investigation was carried out to evaluate the differences between minority wheat species and common wheat to determine the best rheological characteristics, technological quality as well as correlations between rheological and technological traits. The results revealed that hulled wheat species had a high protein content and wet gluten content. Einkorn and emmer were not suitable for ‘classical’ baking processing. But there is potential for other products, e.g. wheat rice (einkorn) or pasta (emmer). Spelt should be possible to be used in ‘classical’ baking industry, but the best solution is to use grain as a mixture with bread wheat. Also, this study showed a genotype variation in the antioxidant activity of einkorn, emmer, spelta and Triticum aestivum.

Effect of Fusarium spp. Contamination on Baking Quality of Wheat

The effect of Fusarium spp. contamination on baking quality of winter common wheat and spelt wheat from different growing systems (organic and conventional) was evaluated by the standard technological quality characteristics and by the rheological system Mixolab. The content of Fusarium spp. mycotoxins [deoxynivalenol (DON), deoxynivalenol-3-βd-glucoside (D3G), 3-acetyldeoxynivalenol (3-ADON), and Zearalenones (ZON)] was determined too. Significantly worse standard technological quality parameters and rheological parameters were determined for artificially inoculated variants of both evaluated wheat species. Statistically significant negative correlation coefficients were discovered between content of mycotoxins and many of technological characteristics, for example, DON content and Zeleny sedimentation for common wheat and spelt (−0.60*; −0.66*) and also between DON content and volume weight (−0.63*; −0.95**) for both wheat species. Resulted Mixolab parameters confirmed that Fusarium spp. infection worsens both protein and starch characteristics for both wheat species. However, effect of Fusarium spp. contamination in spelt wheat was generally less pronounced in comparison with common wheat. Despite of visible shifts of Mixolab curves of samples from organic and conventional growing systems, resulted Mixolab characteristics were statistically comparable.

Organic Cereal Seed Quality and Production

At least 1.8 million hectares of main cereal species are under organic management (includ‐ ing in-conversion areas). As some of the world’s large cereal producers (such as India, China and the Russian Federation) did not provide land use details, it can be assumed that the area is larger than shown here [1]. Comparing this figure with FAO’s figure for the world’s har‐ vested cereal area of 384 million hectares [2], 0.5 percent of the total cereal area is under or‐ ganic management.

Differences in Yield Parameters of Emmer in Comparison with Old and New Varieties of Bread Wheat

Emmer wheat (Triticum diccocum Schrank) belonged to the most frequent species of cereals in the past. Nowadays, it is grown in arid and montane areas in particular. Interest in this cereal species has increased, as it is tolerant to biotic and abiotic stressing factors. Therefore, yield parameters were evaluated in three-year (2007, 2008 and 2010) trials that were carried out in two different localities in the Czech Republic. Results of the research were compared to characteristics of four old and two top modern bread wheat (Triticum aestivum L.) cultivars. The emmer wheat varieties were resistant to usual wheat diseases. They formed their yield by a quantity of productive tillers (2.5), whereas the varieties of bread wheat had less productive tillers (1.5) per one plant. The distribution of assimilates was worse in the emmer wheat plants and it provoked a lower harvest index (0.33) there. Grain yield of the emmer wheat varieties reached 58% of the yield level of the mean of control bread wheat varieties. High crude protein content in grain (17.91%) was an advantage of the emmer wheat varieties; the control bread wheat varieties reached 13.73%. Protein content was positively influenced (P < 0.01) by an ability of the emmer varieties to uptake as much nitrogen as possible from the soil during the flowering period. Adaptability to the land and climatic environmental conditions was another positive characteristic of the emmer wheat landraces in comparison with old and modern bread wheat varieties.