Desflurane consumption during automated closed-circuit delivery is higher than when a conventional anesthesia machine is used with a simple vaporizer-O2-N2O fresh gas flow sequence

The Zeus® (Dräger, Lübeck, Germany), an automated closed-circuit anesthesia machine, uses high fresh gas flows (FGF) to wash-in the circuit and the lungs, and intermittently flushes the system to remove unwanted N₂. We hypothesized this could increase desflurane consumption to such an extent that agent consumption might become higher than with a conventional anesthesia machine (Anesthesia Delivery Unit [ADU®], GE, Helsinki, Finland) used with a previously derived desflurane-O₂-N₂O administration schedule that allows early FGF reduction.Journal ArticleSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Xylanase producing bacteria during malting

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Shifts in microbial community structure during malting with emphasis on xylanase producing bacteria

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Characterization of microbial communities in industrial malting to enhance malt processing quality

Description of topic - Optimization of malt quality in terms of fast filtration is a critical factor in the malting and brewing industry. Since malt quality is inversely related to the concentration of endosperm cell wall components, management of cell wall degrading microorganisms may result in enhanced processing. An essential step in microflora management during malting, however, requires the understanding of the microbial community structure as well as the population dynamics in the processing. Although most studies undertaken so far focus on specific microbial populations using culture-dependent techniques, in this study an integrated approach of different technologies for microbial community profiling is presented as a basis for process optimization. Materials and methods - Both culture dependent and culture independent molecular techniques will be used to characterize the microbial (bacterial) communities in different industrial malting settings, generating malt of different quality. 16S ribosomal DNA-targeted Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis, supported by sequencing of clone libraries, will be used to screen and compare the microbial communities in the different maltings at different stages of the malting process, i.e. from barley up to kilned malt. In addition, the microflora present in used irrigation water and the air will be monitored. Specific patterns associated with high-quality malt will be further investigated, aiming at obtaining cultures responsible for the malt quality. Subsequently, promising bacterial strains will be screened for their cell wall degrading capacity using agar plate assays. Finally, one or more bacterial strains will be selected to evaluate their performance in practice using inoculation trials on a representative pilot scale malting facility. In addition, based on an off line closed-circuit perfusion approach, efforts will be made to manage the microbial community in such a way that desired populations will be stimulated and can be re-inoculated in the process. Novelty - With the increased demand for ‘clean-label’ technology, the malting and brewing industry is seeking for novel approaches to optimize the use of in-house microflora in the malting process. This study may result in the discovery of promising, process-borne microorganisms which may enhance malt processability, or the malting and brewing process in general. Most presumably, this research will reveal previously unidentified species as novel detection technologies will be used to unravel the microbial communities. Altogether, this project might be the basis for further process optimization such as the improvement of the filtration step.status: publishe

Molecular characterization of the microflora during malting to enhance malt quality and processability

Background - Optimization of malt quality with regard to a better lautering performance is a critical factor in the malting and brewing industry. Since malt quality is inversely related to the concentration of endosperm cell wall components such as arabinoxylans, management of cell wall degrading microorganisms may result in enhanced processing. An essential step in microflora management during malting requires the understanding of the microbial community structure as well as the population dynamics in the processing. Objectives – The objective of this study was to characterize the microbial (bacterial) communities in different industrial malting settings and relate these to malt quality and processability. Methods and Conclusions - Both culture-dependent and culture-independent molecular techniques were used to characterize the bacterial communities in different industrial malting settings, generating malt of different quality. 16S ribosomal DNA-targeted Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis, supported by sequencing of clone libraries, were used to screen and compare the microbial communities at different stages of the malting process, i.e. from barley up to kilned malt. In addition, emphasis is put on the xylanase producing microflora. Apart from isolation and identification, the diversity of the xylanase genes was explored by amplifying xylanase genes from the glycosyl hydrolase (GH) family 10 and 11. Specific patterns associated with high-quality malt will be further investigated, aiming at obtaining cultures important for the malt quality. Ultimately, this study may result in the discovery of promising, process-borne microorganisms which may enhance malt processability, or the malting and brewing process in general.status: publishe

A vaporizer-O2/N2O fresh gas flow sequence can lower ADU® desflurane use below that with the Zeus®

SCOPUS: cp.jinfo:eu-repo/semantics/publishe

Molecular characterisation of microbial communities associated with barley during malting, with an emphasis on lactic acid bacteria

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The influence of very thick and fast mashing conditions on wort composition

The mashing process is of highest technological relevance for all following processes of wort and beer production. However, it is time consuming and therefore cost intensive. The influence of important mashing parameters on wort composition was investigated in order to shorten the mashing process by applying the thickest mashes without a negative influence on wort composition. The thickest mash leads to lower energy and water consumption in the brewhouse. On the other hand, the shortest mashing scheme results in the highest throughput. Finally, fine milling, mashing-in above gelatinization temperature, decreased mashing-in pH of 5.2, very thick mash of 1:2.3 malt:water ratio, and a holding time of 30-40 min at 64 degrees C followed by 15-20 min at 72 degrees C guarantees a high extract yield, normal attenuation limit, sufficient FAN level, required buffering capacity, and a reduced fatty acid oxidation. Lowering the pH to 5.2 at mashing-in results in lower glucose levels but the sum of fermentable sugar is not influenced due to a higher level of maltotriose and similar maltose levels. However, not all yeast strains assimilate maltotriose well in industrial fermentations. A mash pH of 5.2, positive for beer flavor stability, may result in a somewhat lower alcohol potential