Addition of yogurt to wort for the production of spirits: Evaluation of the spirit aroma over a two-year period

Triggered by the development of lactic acid bacteria (LAB) during the production of Scotch whisky, this study examined the influence of yeast and LAB inoculation on whisky flavor. Four new spirits were produced using the same process. LAB were added as a form of a Greek yogurt's live culture. In each category (barley and rye), one sample was fermented with Greek yogurt while the other was fermented without it. The spirits were matured and analyzed at five different points. Results from gas chromatography-mass spectrometry (GC-MS) analysis showed basic volatile compounds, along with some important extra compounds with yogurt culture. The most obvious differences were observed in the concentration of butanoic acid, a characteristic acid in spirits undergoing lactic acid fermentation: to identify esters such as ethyl butanoate, ethyl isobutanoate, isoamyl butanoate, and 2-phenylethyl butanoate, they are not typical compounds in whisky.     

Crosslinking copolymerization of cyclic ketenacetals

The crosslinking copolymerization of two 9-substituted 4-methylene-3,5,8,10-tetraoxabicyclo[5.3.0]decanes ( 1 and 2 ) with 3,9-dimethylene-2,4,8,10-tetraoxa-spiro[5.5]undecane ( 3 ) or ethylene glycol dimethacrylate ( 4 ) was investigated. Dependent on the amount of bifunctional agent added, the material properties can be controlled and change from highly viscous to mechanically hard, as the extent of crosslinking increases. Combined with bicyclic monomers, the influence of the crosslinkers on the polymerization shrinkage is low.     

Fractionation at pilot-plant scale of an haemoglobin hydrolysate by strong anionic exchange chromatography Application to the preparation of an amphiphilic peptide

The development and the scale-up of high performance anion chromatography to obtain 1 milligram to 1 gram yields of a peptide fraction from a complex peptic haemoglobin hydrolysate is described here. The chromatographic conditions were developed using a 1 cm³ Mono Q analytical column and progressively scaled-up to a 6 dm³ Q Sepharose Fast Flow column. For easy recovery of peptide and easy adjustment of conditions for final purification, a volatile buffer, ethanolamine/HCl buffer 20 mmol dm⁻³, pH 10·5, was employed; desalting was carried out by a pilot-plant scale electrodialysis which permitted the elimination of 99% NaCl without important loss of peptide (less than 15%). A combination of these techniques with reverse phase HPLC proved a useful strategy for fractionation of a complex peptide mixture and enabled pure peptides to be obtained in sufficient quantities for further analyses and biological tests. The example of preparation and purification of an amphiphilic peptide is described. Its ability to solubilize an insoluble photosensitizer, protoporphyrin IX, was determined in order to study its utilization as a carrier for photochemotherapy. © 1998 SCI.     

Immunocytochemical localisation of para-coumaric acid and feruloyl-arabinose in the cell walls of maize stem

Two phenolic compounds, p-coumaric acid and feruloyl-arabinose, were localised by immunocytochemistry in the cell walls of the apical internode of two lines of maize (Co125 and W401) of different digestibility. The compounds were detected at two stages of cell maturity in the lignified tissues (sclerenchyma, fibres and xylem) and in the medullary parenchyma, which, in the samples studied, was not lignified. p-Coumaric acid is a phenolic acid associated with lignins, which confer resistance on plant cell walls to microbial degradation in the rumen. Feruloyl-arabinose is a compound associated with xylans, the principal hemicelluloses in Gramineae, which are potentially degradable. Labelling of p-coumaric acid decreased in both maize lines with cell age and as the cell walls became lignified. The mass of lignin deposited in the cell walls masked p-coumaric acid, thereby making it less accessible to the antibodies. There was an inverse relationship in the labelling of p-coumaric acid and feruloyl-arabinose. Feruloyl-arabinose was more heavily labelled as the plant cell walls matured in all the lignified tissues of both maize lines and in the parenchyma of the less digestible line. All tissues except the parenchyma were more heavily labelled with both sera in Co125, the more digestible line. © 1998 Society of Chemical Industry.     

Investigations on the synthesis of polyimides with coronand structure via tandem Diels-Alder addition polymerization

The tandem Diels-Alder polymerization of 11 bismaleimides with 4,4'-dimethyl-6,6'-(octamethylene)di-2-pyrone was investigated. Polymers with coronand structure were formed only in case of bismaleimides possessing flexible spacer groups; rigid spacer groups led to network formation.     

Modeling retention and selectivity as a function of pH and column temperature in liquid chromatography

In reversed-phase liquid chromatography (RPLC), the retention of weak acids and bases is a sigmoidal function of the mobile-phase pH. Therefore, pH is a key chromatographic variable to optimize retention and selectivity. Furthermore, at an eluent pH close to the pKa of the solute, the dependence of ionization of the buffer and solute on temperature can be used to improve chromatographic separations involving ionizable solutes by an adequate handling of column temperature. In this paper, we derive a general equation for the prediction of the retentive behavior of ionizable compounds upon simultaneous changes in mobile-phase pH and column temperature. Four experiments, two limiting pH values and two temperatures, provide the input data that allow predictions in the whole range of these two variables, based on the thermodynamic fundamentals of the involved equilibria. Also, the study demonstrates the significant role that the choice of the buffer compound would have on selectivity factors in RPLC at temperatures higher than 25 degrees C.     

Deformation behaviour of an advanced nickel-based superalloy studied by neutron diffraction and electron microscopy

Deformation mechanisms under tensile loading at room temperature have been studied in a polycrystalline nickel-based superalloy containing close to 50 vol.% γ′. In order to identify the effect of γ′ particle size on deformation mechanisms, model microstructures with unimodal γ′ size distributions were developed. The investigations were carried out by combining in situ loading experiments using neutron diffraction and two-site elasto-plastic self-consistent plasticity modelling with detailed post-mortem electron microscopy. The microscopy work also includes results for samples strained at 500 °C. During early plastic deformation, the diffraction data demonstrate that γ and γ′ display the same elastic strain response, indicating that at this stage γ′ is cut by dislocations regardless of the γ′ particle size. Scanning electron microscopy studies showed an abundance of shearing processes in all three microstructures, hence supporting the conclusions drawn from the diffraction experiment. As the material is further deformed, elastic load transfer from γ to γ′ was observed in the medium (130 nm) and coarse (230 nm) γ′ microstructures but not in the fine (90 nm) γ′ microstructure. The load transfer can be explained by assuming that Orowan looping becomes an additional operative deformation mode. Transmission electron microscopy confirmed that in the fine γ′ microstructure deformation takes place by strongly coupled dislocations cutting the γ′, while the medium and coarse γ′ microstructures showed additional signs of Orowan looping.