Technological and nutritional aspect of different hemp types addition: Comparison of flour and wholemeal effect

Addition of non-traditional raw-materials and flours into wheat flour follows contemporary trend of manufacturing nutritionally healthier fermented bakery products. Aim of the study follows this tendency, evaluating nutritional improvement of composite flour and baking potential of prepared wheat-hemp flour composites. Hemp products addition significantly increased both protein and dietary fibre contents. Between five types of hemp flour, differences were observed according to incorporated amount (wheat flour substitution from 5% to 20%). In composites containing 20% of hemp flour and dehulled hemp wholemeal, protein content increased to 14.9% and to 15.7%, respectively (compared to 12.5% proteins in control wheat flour). Dietary fibre content change was governed unequivocally by addition level for both hemp flour and hemp wholemeal. Hemp wholemeal affected the solvent retention capacity (SRC) profile of the wheat flour used in a broader extent than hemp flour done, interacting moreover with addition level applied. Significant diminishing was measured for the sucrose and the lactic acid SRC, which describe physicochemical stage of starch and proteins in prepared composites. Addition of 5% and 20% of dehulled hemp wholemeal decreased the formed SRC from 112.0% to 102.3% and to 64.1%, and the latter SRC from 182.6% to 108.0 and to 78.3%, respectively. Smaller bread volume and worse shape were evaluated as the amount of hemp flour gradually increased; wholemeal form had more or less a positive effect. Correspondingly to that, crumb firmness measured by penetration test was found approximately half for hemp flour composite bread than for the hemp wholemeal ones

Effect of golden and brown linseed fibre on wheat flour pasting, dough properties and bread quality

Wheat flour was enhanced by linseed fibre, characterised by granulation 500–700 μm. Using seeds from 2015 flax harvest, linseed fibre was gained from two golden and one brown linseed varieties (Amon, Raciol and Recital, respectively). Additions at levels 2.5% and 5.0% affected amylases activity and protein technological quality softly, evaluated by Falling Number and Zeleny sedimentation tests, respectively. Both brown and yellow linseed fibre significantly supported extensograph elasticity of non-fermented dough. Baking potential of composites tested evaluated as extensograph energy significantly decreased about 7–18%, likely owing to dilution of dough gluten skeleton. Pasting behaviour of flour composites reflected a hydrophilic character of non-traditional material – amylograph viscosity was elevated from 590 units to ca 700 units by Amon and Recital fibre, and to ca 930 units by Raciol fibre. Pasting profiles of flour composites, recorded by using of Rapid Visco Analyser, confirmed this finding. Dough fermentation was represented by maturograph test, during which the tested samples were differentiated in part according to the dough resistance. Reflecting small modifications in dough visco-elastic properties, specific volumes of bread buns were similar trough whole sample set. A weak worsening of buns vaulting reflected a partial disruption of dough gluten skeleton. Consumer’s quality of all enhanced bread variants was evaluated in category acceptable, determined as crumb penetration (values higher than 20 mm)

Graphene etching on SiC grains as a path to interstellar polycyclic aromatic hydrocarbons formation.

Polycyclic aromatic hydrocarbons as well as other organic molecules appear among the most abundant observed species in interstellar space and are key molecules to understanding the prebiotic roots of life. However, their existence and abundance in space remain a puzzle. Here we present a new top-down route to form polycyclic aromatic hydrocarbons in large quantities in space. We show that aromatic species can be efficiently formed on the graphitized surface of the abundant silicon carbide stardust on exposure to atomic hydrogen under pressure and temperature conditions analogous to those of the interstellar medium. To this aim, we mimic the circumstellar environment using ultra-high vacuum chambers and investigate the SiC surface by in situ advanced characterization techniques combined with first-principles molecular dynamics calculations. These results suggest that top-down routes are crucial to astrochemistry to explain the abundance of organic species and to uncover the origin of unidentified infrared emission features from advanced observations. © 2014 Macmillan Publishers Limited. All rights reserved

Significance of nuclear quantum effects in hydrogen bonded molecular chains

In hydrogen bonded systems, nuclear quantum effects such as zero-point motion and tunneling can significantly affect their material properties through underlying physical and chemical processes. Presently, direct observation of the influence of nuclear quantum effects on the strength of hydrogen bonds with resulting structural and electronic implications remains elusive, leaving opportunities for deeper understanding to harness their fascinating properties. We studied hydrogen-bonded one-dimensional quinonediimine molecular networks which may adopt two isomeric electronic configurations via proton transfer. Herein, we demonstrate that concerted proton transfer promotes a delocalization of {\pi}-electrons along the molecular chain, which enhances the cohesive energy between molecular units, increasing the mechanical stability of the chain and giving rise to new electronic in-gap states localized at the ends. These findings demonstrate the identification of a new class of isomeric hydrogen bonded molecular systems where nuclear quantum effects play a dominant role in establishing their chemical and physical properties. We anticipate that this work will open new research directions towards the control of mechanical and electronic properties of low-dimensional molecular materials via concerted proton tunneling

The energy gap of intermediate-valent SmB6 studied by point-contact spectroscopy

We have investigated the intermediate valence narrow-gap semiconductor SmB6 at low temperatures using both conventional spear-anvil type point contacts as well as mechanically controllable break junctions. The zero-bias conductance varied between less than 0.01 mikrosiemens and up to 1 mS. The position of the spectral anomalies, which are related to the different activation energies and band gaps of SmB6, did not depend on the the contact size. Two different regimes of charge transport could be distinguished: Contacts with large zero - bias conductance are in the diffusive Maxwell regime. They had spectra with only small non-linearities. Contacts with small zero - bias conductance are in the tunnelling regime. They had larger anomalies, but still indicating a finite 45 % residual quasiparticle density of states at the Fermi level at low temperatures of T = 0.1 K. The density of states derived from the tunelling spectra can be decomposed into two energy-dependent parts with Eg = 21 meV and Ed = 4.5 meV wide gaps, respectively.Comment: 9 pages incl. 13 figure

Miocene waterfowl and other birds from central Otago, New Zealand

Copyright © The Natural History Museum 2007Abundant fossil bird bones from the lower Bannockburn Formation, Manuherikia Group, an Early-Middle Miocene lacustrine deposit, 16–19 Ma, from Otago in New Zealand, reveal the “St Bathans Fauna” (new name), a first Tertiary avifauna of land and freshwater birds from New Zealand. At least 23 species of birds are represented by bones, and probable moa, Aves: Dinornithiformes, by eggshell. Anatids dominate the fauna with four genera and five species described as new: a sixth and largest anatid species is represented by just one bone. This is the most diverse Early-Middle Miocene duck fauna known worldwide. Among ducks, two species of dendrochenines are most numerous in the fauna, but a tadornine is common as well. A diving petrel (Pelecanoididae: Pelecanoides) is described, so extending the geological range of this genus worldwide from the Pliocene to the Middle Miocene, at least. The remaining 16 taxa are left undescribed but include: a large species of gull (Laridae); two small waders (Charadriiformes, genus indet.), the size of Charadrius bicinctus and Calidris ruficollis, respectively; a gruiform represented by one specimen similar to Aptornis; abundant rail (Rallidae) bones, including a common flightless rail and a rarer slightly larger taxon, about the size of Gallirallus philippensis; an ?eagle (Accipitridae); a pigeon (Columbidae); three parrots (Psittacidae); an owlet nightjar (Aegothelidae: Aegotheles sp.); a swiftlet (Apodidae: Collocalia sp.); and three passerine taxa, of which the largest is a member of the Cracticidae. The absence of some waterbirds, such as anserines (including swans), grebes (Podicipedidae) and shags (Phalacrocoracidae), among the abundant bones, indicates their probable absence from New Zealand in the Early-Middle Miocene.T. H. Worthy, A. J. D. Tennyson, C. Jones, J. A. McNamara and B. J. Dougla

Evaluation of Non-Fermented Dough from Wheat/Barley/Hemp Composites

Basic wheat-barley flour premixes (70 : 30 and 50 : 50) were enhanced by 5 and 10% of dehulled and hulled hemp seeds wholemeal or by 2 types of hemp fine flour. Barley flour (BF) decreased both protein content and quality by approximately 1.5 and 50%, respectively. In blends, hemp fine flour containing recovered protein level back. BF lowered amylases activity by about 20–25% in maximum; hemp products had no significant effect. Farinograph water absorption was magnified by additions of both alternative flours. Considerable shortening of dough stability and decrease of resistance against over-mixing occurred for all flour tri-composites. Extensigraph dough elasticity increased and extensibility diminished. After dough resting taking 30 min, extensigraph energy of the control sample fell from 141 cm2 to a half as barley flour portion increased. In cereal composites, hemp products demonstrated reversal tendencies. BF lowered water suspension viscosity, but hemp wholemeal H4 and especially fine hemp flour H7 caused a recovery of amylograph maxima to level comparable with wheat control. Correlation analysis confirmed analytical and rheological data agreement – the extensigraph elasticity or energy could be predicted according to the Zeleny value, or the amylograph maximum according to the Falling Number (r = 0.79, 0.90, and 0.65, respectively; P = 99.9%)