Category: 14667-55-1

Wang, Furong published the artcileEffect of free amino acids and peptide hydrolysates from sunflower seed protein on the formation of pyrazines under different heating conditions, Related Products of pyrazines, the main research area is free amino acid peptide hydrolyzate sunflower seed protein pyrazine.

Most research concerning pyrazine formation in the Maillard reaction is mainly focused on free amino acids (FAAs), but limited information is available on the effect of peptides and proteins. In this study, three Maillard model systems (i.e., glucose and native sunflower seed protein, hydrolyzed peptides or FAAs, resp.) were prepared, and their effect on the formation of volatiles were further compared at different heating conditions by using of headspace solid-phase microextraction equipped with gas chromatog./mass spectrometry (HS-SPME-GC/MS). It was found that pyrazines were the characteristic volatile compounds in tested Maillard models, and with increasing heating temperature and time, the varieties of pyrazine formation significantly increased. The optimum reaction condition for pyrazine formation was at 140°C for 90 min, which was subsequently applied to all sets of Maillard models. Further anal. showed that the short chain peptides generated by hydrolyzing sunflower seed protein (SSP), especially the mol. weight ranging from 1.2 to 3.0 kDa, significantly promoted the formation of pyrazines, which highlights the important role of peptides in the Maillard reaction models and is expected to intensify aroma promotion in sunflower seed oil.

RSC Advances published new progress about Headspace solid phase microextraction. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Related Products of pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Wei, Changqing published the artcileChanges Occurring in the Volatile Constituents of Flaxseed Oils (FSOs) Prepared with Diverse Roasting Conditions, Category: pyrazines, the main research area is flaxseed oil volatile constituent diverse roasting condition.

The roasting process is the most significant factor in forming the final flavor character of FSO. A wide variety of volatile constituents in FSO prepared from flaxseeds that were roasted at different temperatures are evaluated by head-space solid phase micro-extraction (HS-SPME) coupled with GC-MS. There are 69 volatile constituents that are tentatively identified, and the sensory variance anal. indicates that all of the FSO samples gives comparable intensity values for the “”oily”” and “”herbaceous””aroma descriptors, and the odor profiles of the FSO samples differed significantly with regards to the “”roasted”” and “”almond”” aromas (p < 0.05). The principal component anal. (PCA) of the volatiles showed the first principal component (PC-1) and the second principal component (PC-2) express 84 and 9% of the volatile component variability in the FSO, resp., which can clearly differentiate FSOs prepared from different roasting conditions. Addnl., the loadings plot further shows that the RFSO correlated more with three groups of volatile constituents according to the degree of roasting (with the total numbers and numbers of specific compounds between brackets): aldehydes (19:2, (E, E)-2,4-pentadienal, (E, E)-2,4-heptadienal), ketones (9:3,2-hexanone, (E)-3-octen-2-one, 5-methyl-2(5H)-furan-one), and heterocyclic compounds (11:4, 2,3-dimethylpyrazine, trimethylpyrazine, 2-ethyl-furan, 2-ethyl-6-methylpyrazine). Practical Applications: Monitoring of the roasting process is an unavoidable task to obtain the desired volatiles and taste to ensure RFSO quality constant at an industrial level. In general, the most adopted indicator to control the degree of roasting in industry is visual inspection, which may not be accurate for the quality evaluation because RFSO presented the same average color value although they are derived from different roasted degree. Different resources will imply in variable volatile constituents for the same type of flaxseeds. It is therefore known that FSOs produced from different roasting processing may be differentiated by their volatile constituents. The results show that the major volatile constituents can be used as chem. markers to distinguish different processed RFSO by the PCA method. The roasting process contributes the most in forming the final flavor character of flaxseed oils (FSOs). By increasing the roasting temperature, the color of FSOs changed gradually from light yellow (0-40 min) to brown (40 min) and finally to deep-brown (50 min). A wide variety of volatile compounds in FSOs are evaluated and compared with those of unroasted FSO by HS-SPME-GC-MS and sensory variance. The sensory variance anal. indicates that the odor profiles of FSO samples differed significantly with regards to the ""roasted"" and ""almond"" aromas (p < 0.05). PCA anal. can clearly differentiate FSOs prepared from different roasting conditions. European Journal of Lipid Science and Technology published new progress about Headspace solid phase microextraction. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Category: pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Lepe-Balsalobre, Esperanza published the artcileVolatile compounds from in vitro metabolism of seven Listeria monocytogenes isolates belonging to different clonal complexes, Category: pyrazines, the main research area is Listeria monocytogenes volatile compound metabolism clonal complex; GC-MS; Listeria monocytogenes; VOCs; biomarkers; volatile compounds.

Microorganisms produce a wide variety of volatile organic compounds (VOCs) as products of their metabolism and some of them can be specific VOCs linked to the microorganism’s identity, which have proved to be helpful for the diagnosis of infection via odor fingerprinting. The aim of this study was to determine the VOCs produced and consumed to characterize the volatile metabolism of seven isolates of different clonal complexes (CCs) of Listeria monocytogenes. For this purpose, dichloromethane extracts from the thioglycolate broth medium were analyzed by gas chromatog. coupled to mass spectrometry (GC/MS). Also, multivariate analyses were applied to the data obtained. Results showed that all the isolates of L. monocytogenes produced de novo isobutanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-(methylthio)-1-propanol, acetic acid, isobutyric acid, butanoic acid, and isovaleric acid. Significant differences were found among isolates for the production amount of these volatiles, which allowed their differentiation. Thus, CC4 (ST-219/CT-3650) and CC87 (ST-87/CT-4557) showed an active volatile compounds metabolism with high consumption nitrogen and sulfur compounds and production of alcs. and acids, and CC8 (ST-8/CT-8813) and CC3 (ST-3/CT-8722) presented a less active volatile metabolism Moreover, within the VOCs determined, huge differences were found in the production of butanol among the seven isolates analyzed, being probably a good biomarker to discriminate among isolates belonging to different CCs. Hence, the anal. of volatile profile generated by the growth of L. monocytogenes in vitro could be a useful tool to differentiate among CCs isolates.

Journal of Medical Microbiology published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Category: pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Chen, Yi published the artcileCharacteristic fingerprints and volatile flavor compound variations in Liuyang Douchi during fermentation via HS-GC-IMS and HS-SPME-GC-MS, Formula: C7H10N2, the main research area is ethyl acetate 1octen3ol volatile organic compound fermentation; Douchi; Fermentation; HS-GC-IMS; HS-SPME-GC-MS; Volatile compounds.

The present study investigates volatile organic compound (VOC) compositional changes in Liuyang Douchi during fermentation via a HS-GC-IMS and HS-SPME-GC-MS combination approach. A total of 115 VOCs were identified from Douchi, most of which were accumulated during pile fermentation Notably, most alcs. and acids decreased with fermentation, while esters, ketones, pyrazines, and phenols accumulated during pile fermentation Depending on the VOCs identified by GC-IMS/MS, the different fermentation stages of Douchi could be facilely distinguished. Of these, 49 VOCs were regarded as the marker VOCs of Douchi in different fermentation stage: hexanol, hexanal, and propanoic acid was the marker VOCs of the black beans before fermentation and contributing beany and grassy odors; 1-octen-3-ol and 3-octanone supplying a mushroom aroma to the Douchi fermented for 3-9 days; and esters and pyrazine, especially Et acetate and 2,6-dimethylpyrazine, contributing the cocoa, fruity, and nutty aromas of matured Douchi.

Food Chemistry published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Wang, Zhouli published the artcileChanges in aroma components and potential Maillard reaction products during the stir-frying of pork slices, Formula: C7H10N2, the main research area is pork slice stir frying aroma component Maillard reaction product.

Stir-fried pork slices are kinds of traditional pork processing products in China, which are usually cooked at high temperature with different seasonings. Because of their special quality and flavor, these products gain consumers ′ preference. However, there are few studies on their physicochem. properties, aroma composition and safety. In this study, the changes in basic components, aroma components and potentially hazardous substances during the stir-frying of pork slices were determined The effects of the different ratios of fat meat to lean meat and vinegar on these indicators were evaluated, and the formation of potential Maillard reaction products was also analyzed. The results indicated that water content, chrominance values of L* and b* exhibited decreasing trends; a* value displayed a trend of decline first and then rising, while the fat content showed a rising trend during the processing. Appropriate stir-frying can promote the formation of aldehydes, while the content of acids, ketones, and terpenes decreased during processing. The change of alcs. has no obvious rule. Some sulfur compounds not found in raw meat were also detected. Different ratios of fat meat and lean meat changed the kinds of aroma components, while vinegar altered the types and their contents. Besides, the contents of acrylamide and 5-HMF changed significantly, and that of benzo(a)pyrene remained at a low level. The addition of vinegar can enhance the amount of acrylamide and 5-HMF but has no obvious effect on benzo(a)pyrene. Besides, 8 kinds of Maillard reaction products (acrylamide, 5-HMF, benzo(a)pyrene, 5-methylfurfural, pyrazine, 4-methylimidazole, pyrraline, and 5- hydroxymethyl – 2-furancarboxylic acid) were determined, and some of them were harmful to product quality and human health. The results showed that the processing time of pork slices should be controlled within 60 min.

Food Control published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Zhang, Xiao published the artcileComparative evaluation of the effects of natural and artificial inoculation on soybean paste fermentation, Computed Properties of 14667-55-1, the main research area is soybean paste natural artificial inoculation fermentation.

Soybean pastes fermented with natural (NIS) and artificial (AIS) inoculation were prepared to evaluate their fermentation characteristics, flavor compounds and microbial community compositions across an entire fermentation period. The results showed that the initial concentrations of free amino acids and aroma compounds were higher in NIS than in AIS, whereas it was opposite at the end of fermentation A larger variation of flavor compounds was observed in AIS, which was associated with higher level of microbial metabolism during AIS fermentation Penicillium and Tetragenococcus were the dominant microbial genera in NIS, while Aspergillus and Pediococcus were predominant in AIS. Correlation anal. of flavor compounds and microbial community dynamics during NIS and AIS fermentation revealed the specific role of microbial taxa in metabolite transformations. Pediococcus acidilactici could be the key microorganism strongly associated with 23 flavor compounds during AIS fermentation Further, Aspergillus oryzae and Pediococcus acidilactici were primarily linked to amino acid metabolism in AIS, whereas Penicillium and Yaniella were found associated with aroma compounds, Tetragenococcus_sp_JNURIC_D6 and Candida solani with that of organic acids in NIS. These findings provide substantial data on the development of flavor-enhancing fermentation starter culture and the better control of flavor ripening in soybean paste production

LWT–Food Science and Technology published new progress about Acids Role: FFD (Food or Feed Use), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Computed Properties of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Chindapan, Nathamol published the artcileProfiles of volatile compounds and sensory characteristics of Robusta coffee beans roasted by hot air and superheated steam, Safety of 2,3,5-Trimethylpyrazine, the main research area is Robusta coffee bean volatile compound hot air superheated steam.

Although superheated steam (SHS) roasting has proved to be capable of improving selected quality of roasted Robusta coffee beans, impact of SHS roasting on aroma characteristics of the beans is not well understood. This study therefore aimed to investigate the effect of SHS roasting on aroma profiles and sensory characteristics of Robusta beans undergone SHS roasting at 190-250°C; results were compared with those of beans roasted by hot air (HA). Sensory characteristics of selected samples were also compared with HA-roasted Arabica beans. Forty five aroma compounds were identified; most were fully developed in beans roasted at 230°C and tended to degrade in beans roasted at 250°C. The SHS roasting led to more extensive formation of aroma compounds contributing to caramel note, while helped reduce formation of major contributors to spicy, roasty and burnt notes. The SHS-roasted Robusta beans exhibited more resemblance to Arabica beans than their HA-roasted counterpart.

International Journal of Food Science and Technology published new progress about Acids Role: FFD (Food or Feed Use), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Safety of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Clarke, Holly J. published the artcileDietary compounds influencing the sensorial, volatile and phytochemical properties of bovine milk, Safety of 2,3,5-Trimethylpyrazine, the main research area is bovine milk dietary compound volatile phytochem property; dairy; feeding system; isoflavones; sensory; volatile organic compounds (VOCs).

The main aim of this study was to evaluate the volatile profile, sensory perception, and phytochem. content of bovine milk produced from cows fed on three distinct feeding systems, namely grass (GRS), grass/clover (CLV), and total mixed ration (TMR). Previous studies have identified that feed type can influence the sensory perception of milk directly via the transfer of volatile aromatic compounds, or indirectly by the transfer of non-volatile substrates that act as precursors for volatile compounds In the present study, significant differences were observed in the phytochem. profile of the different feed and milk samples. The isoflavone formonoetin was significantly higher in CLV feed samples, but higher in raw GRS milk, while other smaller isoflavones, such as daidzein, genistein, and apigenin were highly correlated to raw CLV milk. This suggests that changes in isoflavone content and concentration in milk relate to diet, but also to metabolism in the rumen. This study also found unique potential volatile biomarkers in milk (di-Me sulfone) related to feeding systems, or significant differences in the concentration of others (toluene, p-cresol, Et and Me esters) based on feeding systems. TMR milk scored significantly higher for hay-like flavor and white color, while GRS and CLV milk scored significantly higher for a creamy color. Milk samples were easily distinguishable by their volatile profile based on feeding system, storage time, and pasteurization.

Molecules published new progress about Acids Role: FFD (Food or Feed Use), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Safety of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Sanchez, Carlos published the artcileProfiling of Organic Compounds in Bioethanol Samples of Different Nature and the Related Fractions, Application In Synthesis of 14667-55-1, the main research area is bioethanol VOC gas chromatog mass spectrometry flame ionization detection.

Forty-one bioethanol real samples and related fractions, together with a biobutanol sample, have been analyzed with gas chromatog. coupled to either mass spectrometry (GC-MS) or flame ionization detection (GC-FID). Bioethanol with different water contents, samples originated from several sources of biomass, first- as well as second-generation specimens, distillation fractions, samples stocked in containers made of four different materials, and, finally, a biobutanol sample have been analyzed. The number of the compounds found through GC-MS has been 130, including alcs., aldehydes, ketones, esters, ethers, nitrogen compounds, organic acids, furane derivates as well as other species (e.g., limonene). Afterward, a quant. determination of major components of bioethanol has been carried out. The achieved results have revealed that, besides ethanol and, in some cases, water, species such as acetaldehyde, methanol, and higher alcs., as well as 1,1-diethoxyethane, may be present at concentrations above 500 mg L-1. While the source of bioethanol (nature of the raw material, ethanol generation, or water content) has a direct impact on its volatile organic compound (VOC) profile, the material of the container where the biofuel has been stored does not play a significant role. Finally, the results have demonstrated that, for a given production process, different distillation fractions contain unequal VOC profiles.

ACS Omega published new progress about Alcohols Role: OCU (Occurrence, Unclassified), OCCU (Occurrence). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application In Synthesis of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Saha, Bittu published the artcileOrgano-Cu (II) catalyst: an efficient synthesis of substituted n-heterocycles via double condensation/ tandem oxidation-cyclization/elimination-cyclization reactions from easily accessible precursors, Name: 2,3,5-Trimethylpyrazine, the main research area is organo copper catalyst preparation; diketone diamine copper catalyst tandem cyclization; pyrazine preparation; carbonyl compound phenylene diamine copper catalyst tandem cyclization; quinoxaline preparation.

Several efficient, robust, versatile and straightforward strategies for the diversity-oriented convergent synthesis of a vast range of highly functionalized biol. active N-heterocycles such as quinoxaline, pyrazine, cyanopyrazine derivatives from different easily accessible, inexpensive starting motif has been reported by exploring the promising organo Cu (II) catalyst via double condensation/ tandem oxidation-cyclization/elimination-cyclization reactions. These methodologies have several advantages such as inexpensive, non-toxic starting materials as well as catalyst and easy reaction set-up. Avoid the use of hazardous materials has added another important advantage in these protocols.

Rasayan Journal of Chemistry published new progress about Acid bromides Role: RCT (Reactant), RACT (Reactant or Reagent). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Name: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem