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Bread wheat is the primary bread crop in the majority of countries in the world. The most important product that is manufactured from its grain and flour is yeast bread. In order to obtain an excellent bread, grain with high physical properties is needed for flour and dough. The Russian spring wheat cultivar Saratovskaya 29 is characterized by its exclusively high physical properties of flour and dough. The purpose of this work was to identify the chromosomes carrying the main loci for these traits in Saratovskaya 29 and to map them using recombinant substitution lines genotyped with molecular markers. A set of inter-varietal substitution lines Saratovskaya 29 (Yanetzkis Probat) was used to identify the “critical” chromosomes. The donor of individual chromosomes is a spring cultivar with average dough strength and tenacity. Substitution of 1D and 4D*7A chromosomes in the genetic background of Saratovskaya 29 resulted in a significant decrease in the physical properties of the dough. Such a deterioration in the case of 1D chromosome might be related to the variability of gluten protein composition. With the help of recombinant substitution double haploid lines obtained from a Saratovskaya 29 (Yanetzkis Probat 4D*7A) substitution line the region on the 4D chromosome was revealed in the strong-flour cultivar Saratovskaya 29, with the microsatellite locus Xgwm0165 to be associated with the unique physical properties of flour and dough. The detected locus is not related to the composition gluten proteins. These locus may be recommended to breeders for the selection of strong-flour cultivars. Additionally, a QTL associated with vitreousness of grain was mapped in the short arm of chromosome 7A.

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Differential scanning calorimetry was applied in studies of the effect of gamma irradiation on the potato starch and wheat flour. Essential differences were noticed between endothermal effects observed in concentrated suspensions of the initial and irradiated potato starch and wheat flour heated at a rate of 2.5C min-1, while only small differences were noticed between gelatinization thermal effects recorded for ca. 20% suspensions of the initial and irradiated potato starch samples heated at a rate 10C min-1. Moreover, in the case of wheat flour, a decrease of decomposition temperature of the amylose-lipid complex was concluded.

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Cereal flours are the major component of the Brazilian diet and are also important exportation products. Radioactivity concentrations of 232 Th, 226Ra, 40K and 137Cs were determined in commercial samples of South-Brazilian cereal flours (soy, wheat, corn, manioc, rye and oat flour) to verify the radiological security of these foodstuffs. The measurements were carried out by gamma-ray spectrometry using a 66% relative efficiency HPGe detector. The 40K flour activities,   at 95% of confidence level were in: soy 474±3 Bq . kg-1; corn 30.0±0.3 Bq . kg-1; rye 94±1 Bq . kg-1; manioc 67±1 Bq . kg-1; oat 76±1 Bq . kg-1 and wheat 36.2±0.4 Bq . kg-1. The lower limit of detection for 40K ranged from 0.54 to 1.43 Bq . kg-1. The 137Cs activities in flour samples were: soy £0.07 Bq . kg-1, corn £0.01 Bq . kg-1, oat £0.03 Bq . kg-1 and in wheat, manioc and rye £0.02 Bq . kg-1. The highest concentrations levels of 232 Th and 226Ra were 0.69±0.04 Bq . kg-1 and 0.44±0.03 Bq . kg-1, respectively, in soy flour.

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Production of phytase by Aspergillus niger F00735 strain in submerged fermentation was studied. The effects of various natural substrates with different phytate contents on secretion of extracellular phytase were investigated and the rice flour with about 5 mg g−1 of phytic acid was found to be the best one. The repression effect of high levels of phytic acid or inorganic phosphorous in fermentation medium (corn flour, wheat grit, soy flour, etc.) on production of phytase was also observed. The optimal concentration of rice flour as main carbon sourc e was determined in combination with sodium nitrate. The maximal activity (≈1500 U l−1, 1.5 times higher than using basal medium) was achieved on the 7th day in media containing 7.12% (w/v) rice flour and 0.86% (w/v) sodium nitrate. Supplementation of fermentation medium with different surfactants such as Tween series (20, 40, 60, 65, 80, 85) and Triton X-100 up to 0.1% (w/v) had no significant effects on the secretion of phytase enzyme, meanwhile at concentrations higher than 0.2% (w/v), decrease in enzyme activity was observed.

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Rice brokens were utilized in the development of pasta products. Response surface methodology (RSM) was used to analyze the effect of pre-gelatinized rice flour (from rice brokens), vital gluten, water, glycerol monostearate (GMS) and sodium alginate on the quality responses (sensory, cooking quality, rehydration ratio and solids loss) of the pasta product. A rotatable central-composite design was used to develop models for the responses. Responses were affected most by changes in rice flour and vital gluten levels and to a lesser extent by water, GMS and sodium alginate levels. The maximum sensory score (39.69), cooking quality (12.38), rehydration ratio (3.11) and minimum solids loss (15.64) were identified at 671.05 g kg-1rice flour, 242.40 g kg-1water, 74.70 g kg-1vital gluten, 2.14 g kg-1GMS and 9.71 g kg-1sodium alginate levels.

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Contamination of aerosols, milk and wheat flour with -nuclides, caused by the Chernobyl accident is discussed. Aerosol samples were taken in Tirana area. Milk samples were taken from all the 26 regions of our country. The variations of Cs-137, Cs-134, Ru-106 and Sb-125 radioactivity in the aerosol from May 2 to May 19, 1986 and of I-131, Te-132, Cs-134, Cs-136 and Cs-137 in cow, sheep and she-goat milks are presented. The activity of Cs-137 in wheat flour, taken in 8 regions, of the different contaminated parts of the territory, is discussed, too.

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Various milling parameters, wet gluten content and key dough properties were analyzed for two sister lines of bread wheat with Ae. markgrafii introgressions in genetic background of cultivar Alcedo carrying a set of sub-chromosomal alien segments on chromosomes 2AS, 2BS, 3BL, 4AL and 6DL. The lines revealed higher grain vitreousness, larger particle size of flour, and higher wet gluten content in grain compared to cv. Alcedo. The flour from these lines also showed excellent water absorption and developed more resilient dough. The introgressions in the Alcedo genome caused no reduction in 1,000-grain weight. General improvement of the grain technological properties appears to be the result of introgressions into 2AS, 2BS and 3BL chromosomes. Coincidence of locations of Ae. markgrafii introgressions in chromosome with the QTLs positions for technological traits, revealed in bread wheat mapping populations, is discussed.

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This study aimed to clarify the genetic mechanisms behind wheat flour color. Flour colorrelated traits (L*, a*, and b*) and polyphenol oxidase (PPO) activity are important parameters that influence the end-use quality of wheat. Dissecting the genetic bases and exploring important chromosomal loci of these traits are extremely important for improving wheat quality. The diverse panel of 205 elite wheat varieties (lines) was genotyped using a highdensity Illumina iSelect 90K single-nucleotide polymorphisms (SNPs) assay to disclose the genetic mechanism of flour color-related traits and PPO activity. In 2 different environments and their mean values (MV), 28, 30, 24, and 12 marker-trait associations (MTAs) were identified for L*, a*, b* traits, and PPO activity, respectively. A single locus could explain from 5.52% to 20.01% of the phenotypic variation for all analyzed traits. Among them, 5 highly significant SNPs (P ≤ 0.0001), 11 stable SNPs (detected in all environments) and 25 multitrait MTAs were identified. Especially, BS00000020_51 showed pleiotropic effects on L*, a*, and b*, and was detected in all environments with the highest phenotypic contribution rates. Furthermore, this SNP was also found to be co-associated with wheat grain hardness, ash content, and pasting temperature of starch in previous studies. The identification of these significantly associated SNPs is helpful in revealing the genetic mechanisms of wheat colorrelated traits, and also provides a reference for follow-up molecular marker-assisted selection in wheat breeding.

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Abstract  

Three types of wheat were submitted to two different milling procedures, giving rise to six flours which differed by some physico-chemical characteristics such as particle size, level of damaged starch and protein content. Differential scanning calorimetry was used for monitoring heat-induced structural changes in flour aqueous dispersions 80% water and in doughs 45% water. Differences between the thermal behaviour of the flour dispersions and doughs were explained mainly by differences in protein content. This result was confirmed after partial substitution of flour by gluten. Dynamic mechanical analysis performed at 20°C on the flour doughs indicated, as expected, a linear increase in the elastic modulus with increasing protein content. The results did not bring any evidence that, under these experimental conditions, starch damage might affect gluten hydration.

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The study deals with the effect of chemical and physical modifications on thermal properties and solubility properties of films based on amaranth flour starch–protein hydrolysate. Biodegradable and edible films were prepared by casting a 25% (w/w) solution of hydrolysate containing 20% glycerol and various additions of dialdehyde starch (0, 1 and 5%). After thermal exposure of films at 65 and 95 °C (for 6 and 48 h), thermal properties of films were studied employing differential scanning calorimetry and thermogravimetric analysis. Film solubility tests were performed in an aqueous environment at 25 °C. Chemical and physical modifications of films markedly affect their thermal properties and solubility.

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