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This study investigated the effect of high temperature and drought (during grain-filling) on the quality and components yield of five winter wheat varieties. Drought and drought + heat were found to have a much greater influence on the yield and quality than heat stress alone. Averaged over the varieties, the yield losses were 57% after drought, 76% after drought + heat, and only 31% after heat stresses. The reductions in the unextractable polymeric protein fraction and glutenin-to-gliadin ratio indicated a poorer grain yield quality, despite the higher protein content. Quality deterioration was observed after drought or drought + heat, while high temperatures alone resulted in no change or in a better ratio of protein components. A significant negative correlation was observed between starch granule size and relative protein content after drought.

Spelt (Triticum spelta) is a hexaploid wheat, hulled and with a brittle rachis, and it has interesting agronomic properties. It is used in feed and food, and is becoming more widely used in the growing natural foods market. Spelt differs from wheat in that it has a higher protein content (15.6% for spelt, 14.9% for wheat), higher lipid content (2.5% and 2.1%, respectively), lower insoluble fiber content (9.3% and 11.2%, respectively) and lower total fiber content (10.9% and 14.9%, respectively). There are no important differences in starch, sugar and soluble fiber content, and there is a qualitative diversity at the protein, arabinoxylan and fatty acid levels. [PUBLICATION ABSTRACT]

The aim of this study was to evaluate the capability of the selected Bifidobacterium strains to utilise resistant starch fraction (RS) from native starches of the following origin: wheat, potato, and pea, and their preparations obtained experimentally by physical and enzymatic modifications. Furthermore, the potential influence of the gelatinisation process on the degree of utilisation of RS from the investigated starch samples was studied. The strains B. pseudolongum KSI9, B. animalis KS20a1, and B. breve KN14 were chosen. The native starches and their preparations were characterised by their different contents of the RS fraction, which was metabolised during in vitro fermentation for Bifidobacterium growth. The highest decrease in the RS content was observed in the case of native potato and pea starches after 24-h fermentation by Bifidobacterium strains. The RS fraction of the wheat starch preparation was generally a better substrate for the selected bacteria (19-34%) in comparison with the native wheat starch (0-13%). The gelatinisation process of the native starches and their preparations had a negligible effect on the RS fraction utilised as a substrate for stimulating the growth of the Bifidobacterium strains selected.

Corn is the main cereal cultivated in the world. As feedstuffs for broiler chickens, corn grains provide the majority of the animals' required metabolizable energy and an appreciable amount of protein. However, when submitted to high temperature treatment, such as during drying, the feeding value of corn grain may change significantly. This review reports the current knowledge on changes that occur within corn grains during high temperature drying processes, which can impact on the feeding value of the grains. Studies show that during these high temperature drying processes, structural changes occur within the major components of corn grains, including starch and proteins, which may affect their bioavailability. These changes may have a significant impact on metabolizable energy and zootechnical performance. Drying could also affect the physical traits of corn grains and in turn the feeding behavior of animals. In spite of the importance of grain drying within the corn grain sector, few studies have been devoted to the effect of drying on the feeding value of corn and no consensus has been reached on this subject, possibly because of the different conditions involved in the experiments reported to date. Strict controls over drying conditions and the use of appropriate methods of analysis for a better appreciation of the effects of drying are therefore recommended.

Buckwheat is introduced into the diet as an alternative crop of renewed interest due to its nutritive and health-promoting value. Experiments with animal models have demonstrated that buckwheat flour may alleviate diabetes, obesity, hypertension, and hypercholesterolemia. A number of nutraceutical compounds exist in buckwheat grains and other tissues. These are a rich source of starch, proteins, antioxidants, and dietary fibre as well as trace elements. The biological value (BV) of buckwheat proteins is comparable to BV of other protein sources. Besides high-quality proteins, buckwheat grains contain some components with prophylactic value: flavonoids, fagopyrins, or thiamin-binding proteins. For the food industry, buckwheat grains are a valuable raw material to be used for the production of functional foods. Buckwheat flour may be a valuable and important ingredient in diets or food products, taking into consideration its nutritive value and potential promotion of human health.

Expedient shell tool use among Oceanic peoples is widely known in ethnographic context but oftentimes almost impossible to identify in the archaeological record. This paper examines Anadara antiquata bivalve scrapers, a potential artefact type in the Kingdom of Tonga that is defined by a consistently formed ventral margin. To assess the veracity of tool identification and to ensure that the edge has not been created through natural breakage, a series of experimental studies was undertaken. These illustrate that the functional edge can be formed only through intentional preparation using an inside-out flaking technique on the ventral lip. A low-powered starch test on archaeological specimens further illustrates the presence of starch on the prepared working plane. Finally, an analysis of archaeological specimens from five Tongan sites seeks additional insight on morphological variation within the tool type. L'usage d'outils expédients façonnés de coquillages par les peuples d'Océanie est connu par l'ethnographie, mais il est difficile à identifier dans le registre archéologique. Ce papier présente un potentiel type d'outil en coquillage provenant du Royaume de Tonga, le racloir sur bivalve Anadara antiquata, qui se caractérise par une marge ventrale retouchée. Pour valider ce type d 'outil et vérifier que son tranchant n'est pas crée par le bris naturel, une série d'études furent conduites. Celles-ci indiquent qu'un tel tranchant ne peut être formé que par une préparation délibérée du tranchant employant une retouche de la face intérieure de la marge ventrale de la coquille. Des exemples archéologiques sont soumis à un test au Lugol confirmant la présence de restes d'amidon sur la surface de travail. Dernièrement, une analyse de spécimens archéologiques provenant de cinq sites à Tonga permet la documentation de la variance morphologique de ce type d'outil.

Nia30(145) transformants with very low nitrate reductase activity provide an in vivo screen to identify processes that are regulated by nitrate. Nia30(145) resembles nitrate-limited wild-type plants with respect to growth rate and protein and amino acid content but accumulates large amounts of nitrate when it is grown on high nitrate. The transcripts for nitrate reductase (NR), nitrite reductase, cytosolic glutamine synthetase, and glutamate synthase increased; NR and nitrite reductase activity increased in leaves and roots; and glutamine synthetase activity increased in roots. The transcripts for phosphoenolpyruvate carboxylase, cytosolic pyruvate kinase, citrate synthase, and NADP-isocitrate dehydrogenase increased; phosphoenolpyruvate carboxylase activity increased; and malate, citrate, isocitrate, and alpha-oxoglutarate accumulated in leaves and roots. There was a decrease of the ADP-glucose pyrophosphorylase transcript and activity, and starch decreased in the leaves and roots. After adding 12 mM nitrate to nitrate-limited Nia30(145), the transcripts for NR and phosphoenolpyruvate carboxylase increased, and the transcripts for ADP-glucose pyrophosphorylase decreased within 2 and 4 hr, respectively. Starch was remobilized at almost the same rate as in wildtype plants, even though growth was not stimulated in Nia30(145). It is proposed that nitrate acts as a signal to initiate coordinated changes in carbon and nitrogen metabolism.

Maize (Zea mays L.) plants were grown to the nine-leaf stage. Despite a saturating N supply, the youngest mature leaves (seventh position on the stem) contained little NO3- reserve. Droughted plants (deprived of nutrient solution) showed changes in foliar enzyme activities, mRNA accumulation, photosynthesis, and carbohydrate and amino acid contents. Total leaf water potential and CO2 assimilation rates, measured 3 h into the photoperiod, decreased 3 d after the onset of drought. Starch, glucose, fructose, and amino acids, but not sucrose (Suc), accumulated in the leaves of droughted plants. Maximal extractable phosphoenolpyruvate carboxylase activities increased slightly during water deficit, whereas the sensitivity of this enzyme to the inhibitor malate decreased. Maximal extractable Suc phosphate synthase activities decreased as a result of water stress, and there was an increase in the sensitivity to the inhibitor orthophosphate. A correlation between maximal extractable foliar nitrate reductase (NR) activity and the rate of CO2 assimilation was observed. The NR activation state and maximal extractable NR activity declined rapidly in response to drought. Photosynthesis and NR activity recovered rapidly when nutrient solution was restored at this point. The decrease in maximal extractable NR activity was accompanied by a decrease in NR transcripts, whereas Suc phosphate synthase and phosphoenolpyruvate carboxylase mRNAs were much less affected. The coordination of N and C metabolism is retained during drought conditions via modulation of the activities of Suc phosphate synthase and NR commensurate with the prevailing rate of photosynthesis

The influence of the addition of sugars, sucrose, fructose, and trehalose, modified starches, and hydrocolloids on the rheological properties of raspberry cream fillings prepared with the addition of sucrose (27%), combination of sucrose (17%) and fructose (10%), and combination of sucrose (25.4%) and trehalose (1.6%) was observed. Modified starches, tapioca modified starch (1%) or waxy maize modified starch (1%), hydrocolloids, karaya (0.05%), or guar (0.05%) were added into the cream fillings too. The rheological properties (shear stress and shear rate at different temperatures) were measured by rotational viscometer. The consistency coefficient and flow index were calculated from the measured data. The results showed that waxy maize modified starch or guar gum additions into raspberry cream fillings had a greater impact on the cream filling consistency than tapioca modified starch or gum karaya. All raspberry cream fillings were non-Newtonian stationary fluids at the measured temperatures except cream fillings with sucrose and those with sucrose, fructose and guar gum at a low temperature. These cream fillings were non-stationary rheopectic fluids at 0 deg C. The above-mentioned sugars added influence the rheological properties of the cream fillings in different ways.