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Lithium-sulfur (Li–S) batteries have attracted considerable attention as next-generation energy storage devices owing to their high theoretical specific capacity and safety. However, the commercialization of Li–S batteries is hindered by critical issues, including the migration of the dissolved lithium polysulfides (LiPSs) from the sulfur electrode to the lithium metal anode, resulting in poor cycling stability. Here, we report a multifunctional interlayer configured with an N-doped carbon framework and titanium nitride nanowires on a polypropylene separator (NC/TiN NWs@PP) to suppress the polysulfide shuttling problem. NC/TiN NWs@PP can be obtained by electrospinning and the subsequent scalable solution-based vacuum filtration. The one-dimensional structure of the TiN NWs can shorten the Li-ion diffusion distance with large electrode/electrolyte interfaces. Furthermore, the N-doped carbon framework in the NWs enables facile electron transportation and allows the suppression of the shuttle effect to improve the electrochemical reaction kinetics. The Li–S battery with a NC/TiN NWs@PP separator exhibited enhanced cycling stability and rate capability, indicating that this could be a new research direction for Li–S batteries.

The lithium-ion batteries are recognized as the most promising energy storage system, but it still does not meet the power requirements of electric vehicle batteries owing to low volumetric energy density with the traditional graphite electrode system. In this study, we report the development of a novel electrode system fabricated by implantation of a solid electrolyte interphase (SEI) layer on the graphite surface. The SEI-implanted graphite electrode is made using a lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)-based electrolyte and cycled with a lithium tetrafluoroborate LiBF4-based electrolyte. This new electrode system shows significantly enhanced electrochemical properties owing to the rapid and efficient diffusion of Li ions through the SEI layer between the electrolyte and electrode. This graphite electrode with its pre-formed SEI layer achieves a reversible capacity of 357 mAh g−1 at 0.5 C after 50 cycles, which is significantly higher than that of commercial lithium-ion battery systems constructed with LiPF6 (312 mAh g−1). The resulting unique electrode system could present a new avenue in SEI research for high-performance lithium-ion batteries.

In this study, an analytical method for the determination of α-dicarbonyl compounds (α-DCs), including glyoxal (GO), methylglyoxal (MGO) and diacetyl (DA), in soy sauce was validated using gas chromatography–nitrogen-phosphorus detection. Through Maillard reaction various α-DCs, including GO, MGO and DA have been found in fermented food, dairy products and beverages. The analysis of α-DC was carried out by a derivatisation with o-phenylenediamine. The limit of detection and limit of quantitation were 0.04 and 0.12 μg/kg for GO, 0.04 and 0.13 μg/kg for MGO, and 0.07 and 0.22 μg/kg for DA. The intra- and inter-day accuracy ranged from 92.8 to 109% for GO, from 99.5 to 113% for MGO and from 93.6 to 102% for DA. The intra- and inter-day precision ranged from 3.38 to 12.1% for GO, from 0.67 to 7.65% for MGO and from 1.27 to 9.35% for DA. In 20 commercial soy sauces, α-DCs were found in concentration ranges of 5.60–31.7 μg/mL for GO, 14.4–116 μg/mL for MGO and 0.47–5.48 μg/mL for DA. The developed analytical method could be applied for the determination of α-DCs in soy sauce and motivate investigations related to reducing the content of α-DCs in soy sauce.

In this paper, an anode material system of Co3O4 nanowires composited with reduced graphene oxide (Co3O4 NWs/rGO) and protected by N-doped carbon layer (Co3O4 NWs/rGO@NC) was prepared for lithium ion batteries. The N-doped carbon layer could serve as stress relief matter to reduce volume changes of the Co3O4 NWs/rGO during repeated charge/discharge cycles, and also enhance the reaction kinetics as a highly conductive layer between the Co3O4 NWs and electrolyte. The Co3O4 NWs/rGO@NC electrode delivered a high discharge capacity of ca. 995 mAh g−1 at 0.1 C after 65 cycles, and showed a much better rate performance of 428 mAh g−1 even at a high current rate of 5 C as compared to those of Co3O4 NWs/rGO electrode (203 mAh g−1). The demonstrated electrochemical properties suggested that the N-doped carbon coating on the composite of Co3O4 NWs and rGO could significantly enhance the durability and rate capability of the anode material for high performance lithium ion batteries.

A bacteriocin-producing lactic acid bacterium was isolated from malts. The isolate was identified as Pediococcus acidilactici by morphological, API 50 CHL kit and 16S rRNA analysis, and designated as strain HW01. The antimicrobial activity was maintained over a broad pH range (pH 2–11). Proteolytic enzymes and α-amylase treatments inactivated the bacteriocin activity; while catalase, heat, detergents, and solvents did not. The molecular weight of the crude bacteriocin was approximately 6 kDa by SDS-PAGE. The bacteriocin production phenotype (Bac+) was linked to a 9.8 kb plasmid and was not increased by co-culture with an indicator microorganism. Bacteriocin HW01 inhibited several Gram-positive bacteria, including health-threatening microorganisms (Staphylococcus aureus, Streptococcus mutans, Lactobacillus curvatus, Listeria monocytogenes, and L. innocua). Particularly, Pediococcus damnosus and P. claussenii, which were isolated from spoiled beer, were strongly antagonised by the bacteriocin. P. acidilactici HW01 has tolerance to hop compounds but is unable to grow in a simulated beer environment. The potential of the HW01 strain, as a starter culture in brewing, to control beer spoilage lactic acid bacteria, is discussed.

This study investigated the correlations of α-dicarbonyl compounds (α-DCs), including glyoxal (GO), methylglyoxal (MGO) and diacetyl (DA), formed in coffee prepared under various roasting and brewing methods. The levels of α-DCs in Brazilian coffee beans (Coffea arabica) ranged from 28.3 to 178 μg/mL. Concentration ranges of GO, MGO and DA were 1.31–6.57, 25.5–159 and 1.50–12.9 μg/mL, respectively. The level of α-DCs increased with high roasting temperature, long roasting time, small coffee bean particles, mineral water and espresso brewing. In correlation analysis, the roasting temperature–time showed strong negative correlations with α-DCs in espresso (−0.886) and cold-brew coffee (–0.957). In espresso coffee, there was a strong negative correlation between the α-DCs and coffee bean particle size (−0.918).

Recently, lithium‐ion batteries have reached the limit of low reversible capacity that is deficient for uses in emerging electric devices for mobiles and electric vehicles (EVs). In this work, we have prepared polygonal-stacked Cu2O (PCO) through modified Benedict's reaction by simply controlling concentrations of cetyltrimethylammonium bromide (CTAB). The synthesized PCO materials featuring sharp tip structure showed enhanced capacity than round edge structured PCO. Surface area and structural difference could play critical roles in the electrochemical performances of the PCO materials. Among three different structured Cu2O materials, sharp tip shaped PCO electrode exhibited a high discharge capacity of ca. 402 mAh/g at the 2nd cycle and its discharge capacity appeared to gradually increase to ca. 506 mAh/g up to the 100th cycle. The diffusion coefficient of sharp tip shaped PCO was also larger than PCO with round-structured morphology. The simple synthesis strategy for the resulting unique electrode morphology can allow to understand morphology effects on anode materials for lithium-ion batteries.

Recently, lithium–sulfur (Li–S) batteries have been demonstrated as promising next-generation energy-storage devices. However, their practical application is hindered by poor cycling performance and rate capability. In this study, we prepared a multifunctional interlayer composed of SnO2 nanowires (NWs) and conductive carbon paper (CP) to enhance the electrochemical performance of Li–S batteries. This SnO2 NWs@CP interlayer could efficiently adsorb lithium polysulfides and provide electron-conductive pathways to the sulfur electrode, leading to suppression of the polysulfide shuttle effect and enhancement of the electrochemical reaction kinetics for cycling performance and rate capability. A lithium-sulfur cell fabricated with SnO2 NWs@CP interlayer at a high sulfur loading amount (ca. 4.0 mg cm−2) could deliver a high specific capacity of 815 mAh g−1 (based on sulfur) even after 100 cycles at 0.2 C with a high coulombic efficiency of 98.2%. These results demonstrate that the introduction of multifunctional SnO2 NWs@CP interlayers should be a promising new strategy for the development of high-energy-density Li–S batteries.

Beer is generally considered to be a beverage that has high microbiological stability. However, some undesirable lactic acid bacteria (LAB) can grow in beer and consequently spoil this beverage. In this study, bacteriocin-producing Pediococcus acidilactici K10 was used as a means of bio-acidifying the mash and reducing the spoilage LAB content of the beer. The K10 strain had antimicrobial activity against two beer spoilage LAB strains in wort and did not grow in a beer environment. The K10 strain was inoculated before the mashing step. The effect of K10 as a starter culture was investigated and compared with a control. As a result, filtration time was shortened by 17 min, alcohol content was increased by 137%, foam stability was increased by 156%, bitterness was increased by two bitterness units and there was a significant difference (p

In this study, the effect of the addition of various amounts of adjuncts (rice, wheat, corn and potato at 10 and 20%) on the fermentation period of beer produced from Korean six-row barley was examined. Korean six-row barley is not suitable for brewing because of its relatively high protein/starch ratio. However, this can be offset by partially replacing the barley with adjuncts. Adjunct-added samples were analysed and compared with the control sample made from 100% six-row barley. All adjunct-added samples showed changes in final beer properties (e.g. lower specific gravity, higher alcohol content, beer colour), because the initial free amino nitrogen (FAN) content was decreased and the reducing sugar content was increased. However, potato-added samples showed a higher initial FAN level, resulting in the highest alcohol content. In addition, the colour of the potato-added samples was darker, while the colours of the other samples were lighter. Consequently, the addition of adjuncts at a level of up to 20% had an impact on some of the quality properties of the samples in terms of fermentation period, suggesting the possibility of using Korean six-row barley with adjuncts in brewing. Copyright © 2016 The Institute of Brewing & Distilling

The effect of a ‘bath type’ ultrasound on the fermentation of beer made from Korean six-row barley was studied. Beer samples were treated in an ultrasonication bath for 4 days during primary fermentation. The frequency of the ultrasound was 40 kHz, and the input power was adjusted to 120, 160 and 200 W. Ultrasonic treatment was performed for 2, 6 and 12 h for each input power. The physicochemical and sensory properties, as well as the quality of the beers were measured. Ultrasonication enhanced ethanol production by 13.18% at 160 W. Copyright © 2015 The Institute of Brewing & Distilling