JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
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2018
·Vol. 98
·期 12
·4733-4741
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IF 2.379
Chunfeng Liu,Qi Li,Chengtuo Niu,Feiyun Zheng,Yun Zhao
BACKGROUND Acetaldehyde is an important flavor component in beer which is possibly carcinogenic to humans. Owing to the limitations of present detection methods, only free-state acetaldehyde in beers has been focused on, while acetal in beers has hardly been reported so far. RESULTS A sensitive headspace gas chromatography method was developed for the determination of diethylacetal and acetaldehyde in beer. The column DB-23 was chosen with a total run time of 22.5 min. The optimal addition amount of NaCl, equilibrium temperature and equilibrium time were 2.0 g, 70 °C and 30 min respectively. For both diethylacetal and acetaldehyde analyses, the limit of detection was 0.005 mg L −1 with relative standard deviation < 5.5%. The recoveries of acetaldehyde and diethylacetal were 95–110 and 95–115% respectively. The diethylacetal and acetaldehyde average contents in 24 beer products were 11.83 and 4.36 mg L −1 respectively. The Pearson correlation coefficient between diethylacetal and acetaldehyde was the highest (0.963). Both diethylacetal and acetaldehyde contents increased to a peak value after fermentation for 3 days and then decreased to a lower value. During both normal and forced aging storage, the diethylacetal content decreased and the acetaldehyde content increased gradually over time. When beers were forced aged for 4 days, the increased ratio of acetaldehyde could be above 40.00%. CONCLUSION The newly established method can be used to assess acetaldehyde level and flavor quality in beer more scientifically. © 2018 Society of Chemical Industry
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
CATALYSIS SURVEYS FROM ASIA
·
2018
·Vol. 22
·期 4
·222-229
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IF 3.081
Gao Meixiang,Jiang Haoxi,Zhang Minhua
Series of ZrO 2 supported on the different kinds of SiO 2 carriers were applied in the reaction of 1, 3-butadiene formation from ethanol and acetaldehyde. ZrO 2 /Nano-SiO 2 performed the best performance with the 1, 3-butadiene selectivity 91.43% and the total conversation 52.39%. Prepared catalysts were characterized by N 2 adsorption–desorption, TEM, XRD, temperature-programmed desorption of NH 3 and CO 2 , FTIR spectroscopy of adsorbed pyridine and CO 2 , Raman XPS. The results show that the weak Lewis acid and basic sites are appropriate for BD formation. Furthermore, more and balance acid-basic sites are rather important for the reaction of ethanol and acetaldehyde conversion to BD.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
ENERGY & FUELS
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2022
·
IF 4.654
Nini Zhang,Sheng-Li Chen,Ruyue Zhu,Wei Sun
In this work, we found that besides formaldehyde, an important intermediate in methanol-to-olefins (MTO) conversion, acetaldehyde and acetone were also formed in the MTO reaction and accurately quantified their contents in the reaction system with time on stream. The formation of formaldehyde, acetaldehyde, and acetone follows a sequential reaction. Acetaldehyde could induce the formation of aromatic species, promoting the conversion of lighter aromatic species across cages to polycyclic aromatics and further promoting the formation of insoluble coke, resulting in rapid catalyst deactivation. In addition, acetaldehyde enhances the propagation of the aromatic-based cycle, which leads to the formation of ethylene, thus resulting in the high ethylene selectivity. In contrast, acetone has little effect on the working lifetime of the catalyst and the product distribution of the MTO reaction, although it can be converted to light hydrocarbons similar to that of MTO under the circumstance of the MTO reaction.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2025
·
IF 4.6
Wei Dai,Wenjun Tan,Xuepeng Chen,Jilei Wang,Yougui Yu,Qing Zheng
This study investigates the interconversion between acetaldehyde and its acetal derivatives during the aging process of Baijiu. Acetaldehyde imparts a pungent aroma, while acetal contributes soft fruity and sweet notes to Baijiu. The dynamic equilibrium between these two compounds, mediated by a reversible reaction, significantly influences the aromatic balance and overall flavor harmony of the liquor. By analyzing aging data from Baijiu samples of different alcohol contents (62°, 52°, and 38° ABV) and aromatic types ( Nong , Jiang , Feng , Jian ), we calculated the apparent equilibrium constant (K) and developed a model predicting the simplified equilibrium constant as a function of alcohol content. Results revealed that reduced alcohol content shifts the equilibrium toward acetaldehyde formation, diminishing acetal-derived aromas. This study pioneers a thermodynamic quantitative model for acetaldehyde-acetal interconversion in Baijiu, elucidates the regulatory role of alcohol content in reaction equilibrium through solvent effects. These findings contribute significantly to the scientific understanding of Baijiu aging and offer practical solutions for flavor optimization in Baijiu production, particularly for low-alcohol Baijiu.
研究领域:
食品化学
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风味科学
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物理化学
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热力学
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酿造技术
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产品关联
DOI
高影响因子
CATALYSIS SURVEYS FROM ASIA
·
2023
·Vol. 27
·期 3
·207-216
·
IF 3
Li Shuying,Huang Bin,Jin Changzi,Wang Rui,Jiang Heng,Yang Guang-Sheng,Huang Shengjun
The conversion of ethanol and acetaldehyde to 1,3-butadiene has been an emerging process to produce key chemicals. The preparation of highly efficient catalysts and the understanding of reaction mechanism are current research priority. Herein, mesoporous silica framework confining zirconia (Zr-HMS) was prepared and act as catalyst for 1,3-butadiene production from ethanol and acetaldehyde. The prepared catalysts were characterized by Low-angle X-ray powder diffraction, transmission electron microscopy, N 2 physical adsorption-desorption, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and UV–vis spectra. It has been shown that the Zr-HMS exhibits similar textural properties to supported catalyst (ZrO 2 /HMS). However, regardless of their comparable activities, higher 1,3-butadiene selectivity is obtained over Zr–HMS, which can be due to the different active zirconia species in two catalysts. Mesoporous framework confining character of Zr-HMS can achieve uniformly dispersed zirconia species. Further investigation toward the reaction process has presented new viewpoints for formation and consumption of some typical intermediates and byproducts, which will help to understand the reaction mechanism and construct efficient catalysts for conversion of ethanol and acetaldehyde to 1,3-butadiene.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
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2015
·
IF 2.128
Hui Fei,Gang Xu,Jian-Ping Wu,Li-Rong Yang
DERA SEP (2-deoxy- d -ribose-5-phosphate aldolase cloned from Staphylococcus epidermidis ) shows higher catalytic activity toward 2-deoxy- d -ribose-5-phosphate (DRP) than that of DERA ECO (2-deoxy-ribose aldolase cloned from Escherichia coli ). However, the acetaldehyde tolerance of DERA SEP is still at low level, which limits its use in large-scale applications. Although the mechanism responsible for enzyme inactivation in the presence of solvents is unclear, earlier work indicated the positive correlation between the tolerance of an enzyme for organic solvents and the rigidity of its structure. The acetaldehyde tolerance of DERA SEP was improved by site-directed mutagenesis on the basis of enhancing the rigidity of the protein structure. After calculating the virtual mutation energy (stability) of the enzyme and experimental verification, variant 10 mutant DERA SEP with three amino acid substitutions (T120C, G174I, and G213C) was harvested after three rounds of site-directed mutagenesis. It showed surprisingly high tolerance to acetaldehyde, with almost 70.5% residual catalytic activity after exposure to 300 mM acetaldehyde for 2 h, while the wild-type DERA SEP retained only 11.3% activity under the same condition. Because the rigidity of the protein was increased after incorporating the mutations, the specific activity of the variant 10 was only half that of DERA SEP . Thus, the acetaldehyde tolerance of DERA SEP was efficiently increased by enhancing the rigidity of the structure. These results suggested that the inactivation of DERA by exposure to acetaldehyde may result from protein structural damage.
研究领域:
生物化学
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酶工程
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DOI
高影响因子
ACS Catalysis
·
2019
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IF 12.221
Liu Yang,Tingting Yan,Chuanming Wang,Weili Dai,Guangjun Wu,Michael Hunger,Weibin Fan,Zaiku Xie,Naijia Guan,Landong Li
The formation of the initial carbon–carbon (C–C) bonds in the methanol-to-hydrocarbon (MTH) conversion on acidic zeolite has been hotly debated for decades. Recently, the formation of surface-bound acetyl groups involving C–C bonds during the initial period of the MTH conversion has been disclosed. Understanding the exact C–C bond-containing intermediates triggering the MTH conversion and the critical roadmap of the MTH conversion is essential for the further development of this important reaction. Herein, acetaldehyde from the hydrogenation of surface-bound acetyl species was identified to be responsible for triggering the MTH conversion on H-ZSM-5 zeolite. By combining kinetic studies, spectroscopic analyses, and theoretical calculations, the mechanism and roadmap of zeolite-catalyzed MTH conversion from the initial C–C bonds to the hydrocarbon pool compounds were clearly depicted.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
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2025
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IF 13.5
Yuchen Zhou,Huanmin Liu,Hongxing Li,Xinyu Song,Yonghua Tang,Peng Zhou
The intrinsic surface atomic configuration of photocatalyst without unstable or difficult-to-generate atomic vacancies often limits the formation of effective interaction between metal single atom (MSA) cocatalyst and photocatalyst, thus inhibiting the stability and performance improvement of single-atom photocatalysts. In this study, we present a convenient and cost-effective photochemical oxygen reduction reaction (ORR) mechanism to prepare thermodynamically stable noble metal single-atom cocatalysts on TiO 2 photocatalyst under mild condition (only consuming water and oxygen at 101,325 Pa and 25 °C). The first-principles simulation firstly theoretically reveals that the intrinsic surface configuration of TiO 2 can only produce unstable Pt―O 2 structure. However, ORR occurring on TiO 2 can not only provide one foreign oxygen to coordinate with Pt single atom (PtSA), but also induce one surface lattice oxygen to move toward PtSA, promoting the formation of one thermodynamically stable Pt―O 4 species, demonstrated by the experimental synthesis of PtSA on TiO 2 in oxygen atmosphere instead of inert atmosphere. The obtained stable PtSA-TiO 2 photocatalysts exhibit a photocatalytic rate of 320.4 mmol·g −1 ·h −1 for the coproduction of high-purity hydrogen and value-added acetaldehyde with a selectivity of 99.65%, three-fold higher than the activity of Pt nanoparticles-loaded TiO 2 . This strategy is further extended to other noble metals, such as Rh and Pd.
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2013
·Vol. 171
·期 7
·1559-1567
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IF 1.893
Wang Na,Zhang Wei,Zhou Long-Hua,Deng Qing-Feng,Xie Zong-Bo,Yu Xiao-Qi
A facile tandem route to α,β-unsaturated aldehydes was developed by combining the two catalytic activities of the same enzyme in a one-pot strategy for the aldol reaction and in situ generation of acetaldehyde. Lipase from Mucor miehei was found to have conventional and promiscuous catalytic activities for the hydrolysis of vinyl acetate and aldol condensation with in situ formed acetaldehyde. The first reaction continuously provided material for the second reaction, which effectively reduced the volatilization loss, oxidation, and polymerization of acetaldehyde, as well as avoided a negative effect on the enzyme of excessive amounts of acetaldehyde. After optimizing the process, several substrates participated in the reaction and provided the target products in moderate to high yields using this single lipase-catalyzed one-pot biotransformation.
研究领域:
生物化学
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酶工程
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DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 59
·34069-34077
·
IF 2.936
Minhua Zhang,Xuechao Tan,Tong Zhang,Zheng Han,Haoxi Jiang
A deactivation study on the ethanol/acetaldehyde conversion to 1,3-butadiene over a ZnO promoted ZrO2–SiO2 catalyst prepared by a sol–gel method was performed. The samples were characterized by N2 adsorption–desorption isotherms, scanning electron microscopy (SEM), NH3 temperature programmed desorption (NH3-TPD), X-ray powder diffraction characterization (XRD), thermogravimetric analyses (TGA), Fourier transform infrared resonance (FT-IR), 13C magic-angle spinning nuclear magnetic resonance (13C NMR) and X-ray photoelectron spectroscopy (XPS). The pore structure characteristics and surface acidity of Zn0.5–Zr–Si catalysts were largely decreased with time-on-stream and no crystal structure was formed in the used catalyst, indicating that the deactivation was caused by carbon deposition. Two main types of carbon deposition were formed, namely low-temperature carbon deposition with the oxidation temperature of around 400 °C and high-temperature carbon deposition with the oxidation temperature of 526 °C. The carbon species were mainly composed of graphitized carbon, amorphous carbon, carbon in C–O bonds and carbonyls. The deactivated catalyst could be regenerated by a simple oxidation process in air. Adding a certain amount of water into the feed had a positive effect on reducing the carbon deposition.
研究领域:
催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
COMBUSTION AND FLAME
·
2018
·
IF 4.494
Xiaoyuan Zhang,Lili Ye,Yuyang Li,Yan Zhang,Chuangchuang Cao,Jiuzhong Yang,Zhongyue Zhou,Zhen Huang,Fei Qi
Acetaldehyde oxidation was investigated in a jet-stirred reactor at temperatures from 460 to 900 K, equivalence ratios from 0.5 to 4.0 and pressures of 710–720 Torr. Reactive intermediates under low-temperature conditions, such as methylperoxy, methylhydroperoxide and ketohydroperoxide were detected using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). A kinetic model for acetaldehyde oxidation was constructed by incorporating recent theoretical and modeling progress of acetaldehyde kinetics, as well as the calculated results of H-atom abstraction reactions of acetaldehyde by acetylperoxy, methylperoxy and methoxy in this work. The present model was then comprehensively validated against the measurements in this work and the experimental data from literature. Modeling analysis reveals that the main chain-branching pathways of acetaldehyde under low-temperature oxidation conditions are the decomposition of acetylhydroperoxide and methylhydroperoxide. The second O 2 -addition process was verified to exist in the low-temperature oxidation of acetaldehyde as ketohydroperoxide was observed, while its contribution to the overall reactivity was found to be minor under present investigated conditions. On the other hand, the sub-mechanism of acetylperoxy is crucial in the low-temperature regime while the methyl oxidation mechanism dominates in the negative temperature coefficient (NTC) region at all equivalence ratios investigated in this work.
研究领域:
化学动力学
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燃烧科学
·
反应机理研究
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Shuai Liu,Yang Meng,Chunlin Luo,Huiwen Zhu,Yunshen Song,Honglei Zhang,Tao Wu
The emergence of global warming issues has triggered the interest in producing carbon-neutral energy sources and fossil-based chemicals from affordable and renewable feedstocks (e.g., bio-ethanol). Herein, the synthesis of highly dispersed CuS/TiO 2 photothermal catalysts is reported for simultaneously converting ethanol into hydrogen and acetaldehyde under simulated sunlight. The catalyst achieved a hydrogen evolution rate of 51.61 mmol g −1 h −1 and an acetaldehyde production rate of 48.63 mmol g −1 h −1 , with a maximal acetaldehyde selectivity of 97% among carbon-containing products. Compared to pristine TiO 2 , the introduction of plasmonic CuS largely extended the light adsorption range and enhanced the photothermal performance, whilst the formation of heterojunction structure improved the charge transfer and separation efficiency. The density functional theory calculation results demonstrate that CuS/TiO 2 composite interfaces could significantly lower the activation energy of ethanol dehydrogenation reaction and improve hydrogen evolution reaction ability. This study provides deep insight into understanding and optimizing hot carrier dynamics in photothermal catalytic systems.
研究领域:
能源化学
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催化材料科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）