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Cereal Research Communications
Authors: E. Ivanišová, M. Ondrejovič, D. Chmelová, T. Maliar, M. Havrlentová, and L’. Rückschloss

The aim of this study was to evaluate the antioxidant activity of four milling fractions of purple wheat breeding lines grown in 2010. Radical scavenging activity by the DPPH assay and reducing power of the samples were determined, as well as the content of polyphenols, flavonoids and anthocyanins. The obtained results showed that flour fractions (break and reduction flour) had lower total antioxidant potential than bran fractions (fine and coarse bran). A significant correlation was obtained between the DPPH and reducing power assay (R 2 = 0.87). The correlation between antioxidant assays and polyphenol, flavonoid and anthocyanin content suggested that polyphenols in cereals are responsible for the antioxidant activities.

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We have collected sixteen total diet samples from two socioeconomic groups in Turkey by duplicate portion techniques. Samples were homogenized with titanium-blade homogenizer, freeze dried and analyzed for their minor and trace elements mostly by neutron activation analysis. Bread and flour samples were also collected from the same regions and analyzed similarly by instrumental neutron activation analysis. We have determined concentrations of more than 25 elements in total diets, bread and flour, and fiber and phytate in total diets. We have determined daily dietary intakes of these population groups, probable source of elements through correlation coefficients, and enrichment factor calculations.

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The presence of genetically modified organisms (GMOs) was analysed in food samples from the Czech food markets. Four different types of food samples (soya beans, soya bean products, maize flour, and rice) were collected at twelve places in four terms in the years 2008–2013. It represents a total 1152 food samples. Soya and maize were chosen, because these are the major transgenic crops grown worldwide. Increased cultivation of GM rice in China, India, Indonesia, and the Philippines has been observed. Polymerase chain reaction-based methods were applied to detect GMOs. GMOs were detected in 107 samples (9.3%). The results show that in food from the Czech food market GMOs mainly in maize flour and rice were found. GM maize was detected in 63 (21.9%) maize flour samples. Maize lines MON810, NK603, and Bt176 were detected in 14 (22%), 9 (14%), and 1 (1.6%) maize flour samples, respectively. Unauthorised GM rice was detected in 39 (13.5%) rice samples. Unauthorised rice Bt63 was detected in one sample of rice. Roundup Ready soya was detected in 4 (1.4%) soya bean samples and in 1 (0.35%) soya product sample. These results were compared with results of the world´s studies.

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The derivatographic method was used for the quantitative determination of water content in selected flour and fat products. Weight losses and thermal effects taking place in the examined products under the influence of heat were read from the obtained derivatograms. Percentage water contents were calculated from TG curves within the range from 5.6% (rice cereal) to 16.0% (potato flour), based on the diagrams recorded within the temperature range 20–1000C, narrower temperature ranges of dehydration and decomposition processes were determined. In addition, the number of stages of thermal decomposition of the examined products was determined and appropriate kinetic parameters were calculated. The values of the activation energy (E a) of dehydration, frequency factor (A) and reaction order (n) were calculated from TG, DTG andT curves within the temperature range from 20 to 90C. For potato flour the following values were obtained:E a=27.825 kJ/mol,A=1.05105 1/s andn=2.9710−3, for the remaining samples under investigation the activation energyE a is several dozen kJ/mol and the reaction ordern is very low. The obtained data show that the dehydration process under study is mainly associated with evaporation of water adsorbed on products and to less extent with chemical processes.

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Effects of hydrocolloids (arabic gum, guar gum, and xanthan gum) on the physicochemical and rheological properties of whole-barley fortified cracker flour were determined using solvent retention capacity, alveograph, and Mixolab profiles. Results showed that the water absorption of whole-barley fortified cracker flour was reduced by the additional arabic gum. Besides, arabic gum was more effective in reducing the resistance to inflation and improving the extensibility of whole-barley fortified dough. Mixolab parameters indicated that the weakening of gluten proteins and the rate of starch retrogradation in whole-barley fortified cracker dough were reduced by the presence of arabic gum. Guar gum and xanthan gum promoted the rate of protein breakdown, but slowed down the starch gelatinization and retrogradation rate during the Mixolab heating-cooling cycle. In conclusion, involved arabic gum rather than guar gum or xanthan gum is benefit to improve the baking quality of wholebarley fortified saltine crackers.

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The anthocyanin content of spring and winter wheat cultivars and their hybrids with purple and blue coloured grains was evaluated under Hungarian growing conditions. In all 3 years the anthocyanin content of blue grained wheats was significantly higher than that of purple ones. Anthocyanin content was influenced by environmental factors. In the progenies of crosses between Hungarian hard red winter wheat cultivars and blue-grained varieties, the anthocyanin content of the grind was 21–157 mg/kg, while that of the flour was 5.3–17.4 mg/kg. Consequently, most of the anthocyanin content was in the bran. The high anthocyanin content of blue and purple wheat varieties can be applied successfully for elevating the anthocyanin content of bakery products if whole-meal flour or bran is used.

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Wheat is one of the most grown crops in Saudi Arabia. It is grown in various regions of the country. Accurate knowledge of the elemental concentrations in wheat and its products (bran and flour) is of great importance from a nutritional point of view. Wheat samples were obtained from the Al-Qusim region, 300 km northwest of Riyadh, and analyzed. Up to 50 elements (Al, Sb, As, Ba, Br, Cd, Ca, Cs, Cl, Cr, Co, Cu, Ga, Au, Hf, In, I, Ir, Fe, Mg, Mn, Hg, Mo, Ni, K, Rb, Sc, Se, Ag, Na, Sr, Ta, Te, Th, Sn, Ti, W, U, V, Zn, Zr, Ce, Dy, Eu, La, Lu, Nd, Sm, Tb and Yb) were determined in the wheat products. It was observed that the elemental content of bran was much higher than that of white flour.

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Water states and displacements can be investigated with thermogravimetry (TG) either in its classical or in the Knudsen version (where standard pans are replaced with Knudsen cells). The case of wheat flour dough is considered in various steps of bread making, namely, mixing, proofing, baking, staling. The split of DTG signals into various components (gaussian functions) support the assumption that the overall dough water is partitioned into various fractions. Few comments are devoted to water displacements during freezing.

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We describe an application of DSC as an analytical ‘fingerprinting’ method that has been used to characterize the thermal properties of wheat starch in low-moisture, wheat-flour-based baked products, including cookies, crackers, and pretzels. This use of DSC has enabled us to relate starch thermal properties, on the one hand, to starch structure, and on the other hand, to starch functionality, in terms of baking performance and finished-product quality.

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Twelve biological-matrix, agricultural/food reference materials, Corn Stalk (Zea Mays) (NIST RM 8412), Corn Kernel (Zea Mays) (NIST RM 8413), Bovine Musele Powder (NIST RM 8414), Whole Egg Powder (NIST RM 8415), Microcrystalline Cellulose (NIST RM 8416), Wheat Gluten (NIST RM 8418), Corn Starch (NIST RM 8432), Corn Bran (NIST RM 8433), Whole Milk Powder (NIST RM 8435), Durum Wheat Flour (NIST RM 8436), Hard Red Spring Wheat Flour (NIST RM 8437) and Soft Winter Wheat Flour (NIST RM 8438) were developed. They were characterized with respect to elemental composition via two extensive international interlaboratory characterization campaigns providing 303 reference and informational concentration values for 34 elements (Al, As, B, Ba, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, F, Fe, Hg, I, K, Mg, Mn, Mo, N, Na, Ni, P, Pb, Rb, S, Sb, Se, Sr, Ti, V, W, Zn) of nutritional, toxicological, and environmental significance. These products are available to the analytical community, for quality control of elemental composition analytical data, from the Standard Reference Materials Program, National Institute of Standards and Technology, Gaithersburg, MD, USA.

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