Influence of high molecular weight polypeptides on the mouthfeel of commercial beer

Low malt beers have high sales volumes in Japan, but improving their mouthfeel, including softness, smoothness and decreasing astringency, is challenging because the compounds responsible remain unclear. In this study, beer was fractionated by preparative size‐exclusion chromatography, with the polypeptide and maltodextrin fractions purified using solid‐phase extraction and ion‐exchange resin. Sensory data from a spike test showed that the mouthfeel (softness, smoothness, and reduced astringency) of low malt beer was improved both by the degree of polymerisation (DP) of maltodextrins (DP of 2‐10; at increased concentration of 40 to 60%; P < 0.01) and by 10 ‐ 20 kilodalton (kDa) high molecular weight (HMW) polypeptide and 2‐3 kDa low molecular weight polypeptide fractions (at a 50% increase in concentration; P < 0.01). Furthermore, highly purified 10 to 20 kDa HMW polypeptides improved the softness and smoothness and decreased the astringency (at a 25% increase in concentration). This report is the first to provide experimental sensory data indicating that HMW polypeptides improve the mouthfeel of beer. Based on these findings, a new low malt beer was developed that showed significantly higher levels of the 10‐20 kDa HMW polypeptides with an overall improved mouthfeel. Mass spectrometric analysis of the 10 to 20 kDa proteins identified several unique foam positive proteins, including barley dimeric alpha‐amylase inhibitor‐1 and non‐specific lipid‐transfer protein 1. These 10‐20 kDa HMW proteins are likely to be responsible for the improved mouthfeel of beer. © 2020 Kirin Holdings Kabushik Kaisha Co. Ltd. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling     

A novel gas turbine cycle with hydrogen-fueled chemical-looping combustion

In this paper we have proposed a novel gas turbine cycle with hydrogen-fueled chemical-looping combustion, and the system study on two hydrogen-fueled power plants, the new gas turbine cycle and an advanced gas turbine cycle with H₂/O₂ combustion, has been investigated with the aid of exergy principle (EUD methodology). The hydrogen fueled chemical-looping combustion in the new gas turbine cycle consists of two successive reactions: hydrogen fuel is reacted with metal oxide (reduction of metal oxide), and then instead of air or pure oxygen, the reduced metal is successively oxidized by the saturated air. As a result, the new hydrogen-fueled gas turbine cycle has a breakthrough performance, with at least about 12 percentage-point higher efficiency compared to the gas turbine cycle with H₂/O₂ combustion, and will be environmentally superior due to complete elimination of NO_x formation. The promising results obtained here indicated that this novel gas turbine cycle with hydrogen-fueled chemical looping combustion could make a breakthrough in efficient use of hydrogen energy in power plants.     

Treatment with hydrogen peroxide improves the physicochemical properties of dietary fibres from Chinese yam peel

Yam is a common ‘medicine food homology’ vegetable in Asia, and its peel is often considered a food residue during processing or cooking. In this work, the effects of hydrogen peroxide modification on the dietary fibres (DFs) from Chinese yam peel (CYP) were investigated. The structural characteristics of soluble dietary fibre (SDF), insoluble dietary fibre (IDF), modified soluble dietary fibre (MSDF) and modified insoluble dietary fibre (MIDF) were analysed using Fourier-transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, granularity analysis, scanning electron microscopy and GC-MS (monosaccharide composition). As results, after modification with hydrogen peroxide, the sizes of the DFs were reduced and MIDF exposed more cellulose. Experiments on the physicochemical and functional properties of DFs showed that MSDF and MIDF obtained a better water holding capacity, oil absorption capacity, swelling capacity and absorption abilities with altered structures, which is of great importance in food processing and development.     

The spread of fire from adjoining vehicles to a hydrogen fuel cell vehicle

Two vehicle fire tests were conducted to investigate the spread of fire to adjacent vehicles from a hydrogen fuel cell vehicle (HFCV) equipped with a thermal pressure relief device (TPRD) : – 1) an HFCV fire test involving an adjacent gasoline vehicle, 2) a fire test involving three adjoining HFCV assuming their transportation in a carrier ship. The test results indicated that the adjacent vehicles were ignited by flames from the interior and exterior materials of the fire origin HFCV, but not by the hydrogen flames generated through the activation of TPRD.     

Study on the chimney effect in natural air‐cooled electronic equipment casings under inclination: Proposal of a thermal design correlation that includes the porosity coefficient of an outlet opening

Natural air‐cooling technologies for electronic equipment have the important advantages of no fan and high reliability. However, natural air cooling has lower cooling capability than fan air cooling, so enhancement of its cooling capability is required. This paper presents the results for experimental casings designed to employ the chimney effect in natural air‐cooled electronic equipment. The system casing is inclined to enhance the effectiveness of natural air cooling. Experiments were carried out using a thin laptop PC. We investigated the effect on cooling capability produced by inclining the casing and by varying the outlet positions and numbers and the porosity coefficient of the outlet openings. The results show that the temperatures inside the casing and heater surfaces are slightly diminished by the effect of increased inclination and porosity coefficient of outlet openings. Moreover, the increase in natural circulation flux in the casing was quantitatively proven by experiments. In addition, the experimental data were reduced to a Nusselt number–Rayleigh number correlation, , by using a modified reference length. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(2): 122–136, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20103     

Microstructural controls of titanate nanosheet composites using carbon fibers and high-rate electrode properties for lithium ion secondary batteries

Composite electrodes of reassembled titanate and two kinds of carbon fibers were prepared and their high-rate electrode properties were examined. Multi-walled carbon nanotubes (MWNT) and vapor-grown carbon fibers (VGCF) were used for preparing the composites. The electronic conductivity of the MWNT composites increased with increasing contents of MWNT and exhibited a typical insulator-conductor transition. The MWNT composite with a MWNT content of 50 wt.% showed a capacity of 150 ± 5 mAh (g titanate)⁻¹ at a discharge rate of 0.67 C, and did not show a good high-rate capability due to the large content of hydrated water. The effect of the porous structure of the electrodes was revealed in the high-rate electrode properties of the microstructurally controlled composites with both MWNT and VGCF. The composites with 50 wt.% VGCF and 10 wt.% MWNT showed a reversible capacity of approximately 160 mAh (g titanate)⁻¹ at a discharge rate of 0.63 C and almost no capacity fading at relatively large discharge rate up to 19 C. A composite electrode with excellent high-rate capability was obtained by the microstructural control with carbon fibers.     

Tool for inspecting faults from incorrectly cleaved fiber ends and contaminated optical fiber connector end surfaces

We investigated and analyzed faults in field installable connection due to incorrectly cleaved fiber ends and manufactured physical contact (PC)-type connectors with contaminated end surfaces in optical access fiber networks. The insertion and return losses of fiber connections using incorrectly cleaved fiber ends might be at worst more than 40 dB and less than 30 dB, respectively. With PC-type connectors whose end surfaces are contaminated, the insertion and return losses might be at worst 8.7 and 27 dB, respectively. We developed an inspection tool for cleaved fiber ends and connector end surfaces as a countermeasure. The proposed tool has a simple structure and does not require focal adjustment. It can be used to inspect and clearly determine whether a fiber has been cleaved correctly and whether there is contamination or scratches on the connector end surfaces. The tool requires a slight increase of 11% in operation time compared to conventional fiber end preparation and assembly procedures. The proposed tool provides a simple and cost-effective way to inspect cleaved fiber ends and connector end surfaces and is suitable for field use.     

Microbolometer Terahertz Focal Plane Array and Camera with Improved Sensitivity in the Sub-Terahertz Region

Journal of Infrared, Millimeter, and Terahertz Waves - A pixel in an uncooled microbolometer terahertz (THz) focal plane array (FPA) has a suspended structure above read-out integrated circuit...