Category: Pyrazines

Hou, Lixia published the artcileDetermination of main bitter compounds in soaked and germinated sesame pastes, COA of Formula: C7H10N2, the main research area is sesame paste germination soaking bitter compound determination; bitterness; germination; non-volatile; sesame pastes; volatile compounds.

The flavor and taste of the foods play an important or even a decisive role in the acceptance and preference of the consumers. It was found that the sesame paste prepared with the germinated sesame seeds was bitter in our previous experiment In the study, the volatile and non-volatile bitter-taste components of the sesame paste samples were comprehensively analyzed. 2-methylbutanal, hexanal, acetic acid, and butyric acid were the predominant volatile compounds in the soaked and germinated sesame pastes. Oxalate was significantly reduced by the germination (p < 0.05). The contents of sesaminoltriglucoside in sesame pastes ranged from 129.04 to 217.57μg/g. Both total and individual free amino acid contents increased with the prolongation of the germinating time. The bitter-taste amino acid Arg had the highest score of Taste Activity Value for the bitterest sample made from the seeds germinated for 36 h. The bitter-tasting Arg was first reported to impart a bitter taste to the germinated sesame paste. Journal of Oleo Science published new progress about Alcohols Role: ANT (Analyte), FFD (Food or Feed Use), ANST (Analytical Study), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, COA of Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Lin, Li-Yun published the artcileVolatile Variation Theobroma cacao Malvaceae L. Beans Cultivated in Taiwan Affected by Processing via Fermentation and Roasting, Product Details of C7H10N2, the main research area is Theobroma cacao Malvaceae bean fermentation roasting processing volatile variation; amino acids; cocoa bean flavors; fats and fatty acids; fermentation; pyrazine and esters; roasting; triacylglycerols; volatile changes.

After being harvested, cacao beans are usually subjected to very complex processes in order to improve their chem. and phys. characteristics, like tastefulness with chocolate characteristic flavors. The traditional process consists of three major processing stages: fermentation, drying, and roasting, while most of the fermentation is carried out by an on-farm in-box process. In Taiwan, we have two major cocoa beans, the red and the yellow. We proposed that the major factor affecting the variation in tastes and colors in the finished cocoa might be the difference between cultivars. To uncover this, we examined the effect of the three major processes including fermentation, drying and roasting on these two cocoa beans. Results indicated that the two cultivars really behaved differently (despite before or after processing with fermentation, drying, and roasting) with respect to the patterns of fatty acids (palmitic, stearic, oleic, and arachidonic); triacylglycerols:1,2,3-trioleoyl-glycerol (OOO); 1-stearoyl-2,3-oleoyl-glycerol (SOO); 1-stearoyl-sn-2-oleoyl-3-arachidoyl- glycerol (SOA); 1,3-distearyol-sn-2-oleoyl-glycerol (SOS); organic acids (citric, tartaric, acetic, and malic); soluble sugars (glucose and fructose); amino acids; total phenolics; total flavonoids; and volatiles. Our findings suggest that to choose specific processing conditions for each specific cocoa genotype is the crucial point of processing cocoa with consistent taste and color.

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

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Kouassi, Ange Didier D. published the artcileEffect of spontaneous fermentation location on the fingerprint of volatile compound precursors of cocoa and the sensory perceptions of the end-chocolate, Computed Properties of 14667-55-1, the main research area is cocoa chocolate volatile compound fermentation fingerprint sensory perception; Aromatic compound precursors; Chocolate; Cocoa beans; Fermentation location; Sensory perceptions.

Cocoa pod-opening delay and bean fermentation promote the organoleptic quality of chocolate. The present research investigated the changes in the volatile fingerprint of cocoa harvested at a traditional plantation. Cocoa beans extracted from 2-days pod-opening delay were simultaneously fermented for 5 days using container and then sun-dried to 7-8% moisture content at five different locations: Akoupe, San Pedro, Soubre, Djekanou and Daloa. The aromatic anal. were done on cocoa using the HS-SPME-GC/MS technique. Professional panelists evaluated the sensory perceptions of the chocolate. The results shows that cocoa fermented in both Daloa and Soubre regions were differentiated by 2,3-butanediol while those processed in other regions presented highest acetoin content. However, fermented cocoa from Soubre region exhibited most amount of 2,3-butanediol, diacetate A whereas 2,3,5,6-tetramethylpyrazine differentiated those from Daloa region. Sensory properties of chocolate were not linked to the aromatic compound precursors profile of beans. The fermentation performed in San Pedro region promote both the generation of more desirable aromatic compounds of cocoa and sensory attributes of the finished chocolate. The fermentation location generates a greater differentiation of the volatile fingerprint of cocoa and the sensory perceptions of the finished chocolate.

Journal of Food Science and Technology (New Delhi, India) published new progress about Alcohols Role: ANT (Analyte), FFD (Food or Feed Use), ANST (Analytical Study), 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

Han, K. published the artcileEffect of the different baking processes on the aroma profiles of Shanxi aged vinegar mashes, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is Shanxi aged vinegar mash aroma baking process.

As one of the typical appreciated seasonings, Shanxi aged vinegar is famous all over the world for its unique aroma formed during the baking stage. To evaluate the influence of two baking methods on the aroma profiles, headspace solid-phase microextraction (HS-SPME) in combination with gas chromatog.-mass spectrometry (GC-MS) were carried out, and the odor intensity was evaluated by odor activity values. Results showed that there were 72 volatile compounds that could be identified and quantified in the analyzed samples. Moreover, among them, the odor activity values (OAV) of 35 compounds were ≥ 1, and the contents of acetic acid, Et acetate, and acetoin were significantly higher than the other volatile compounds There were 17 odor-active compounds newly produced after baking stage. Based on the principle components anal. (PCA), 11 newly produced volatile compounds as well as benzeneacetaldehyde and furfural, of which the OAVs had remarkable differences in two baking methods, were closely associated with the baking process. Addnl., acetophenone was formed specifically in the traditional methods, and five odor-active compounds (3-methylbutyl-acetate, hexanal, 2,3-dimethyl-5-ethylpyrazine, trimethyloxazole, and di-Me disulfide) were detected only in the modern method. In conclusion, baking process has important influence on the formation and composition ratio of aroma profiles in Shanxi aged vinegar. The results obtained from the present work might provide guidance for improvement of the production process and quality optimization of Shanxi aged vinegar.

International Food Research Journal published new progress about Alcohols Role: ANT (Analyte), FFD (Food or Feed Use), ANST (Analytical Study), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Recommanded Product: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Liu, Lichun published the artcileCharacterization and identification of different Chinese fermented vinegars based on their volatile components, Product Details of C7H10N2, the main research area is Chinese fermented vinegar volatile component; KS algorithm; PCA; PLS-DA; comparative analysis; traditional Chinese vinegars; volatile components.

In this study, volatile components of 40 Chinese fermented vinegar samples, made from different raw materials, starters, and processing technologies, were collected from different geog. origins in China (Shanxi, Jiangsu, Sichuan, and Fujian Province) and their volatile components were analyzed by headspace-solid-phase microextraction-gas chromatog.-mass spectrometry. Sixty-two aroma compounds have been identified by NIST library combined with retention index, mainly including esters, heterocyclics, acids, aldehydes, and ketones. In addition, multivariate anal. including principal component anal. and partial least squares-discriminant anal. (PLS-DA) were carried out to discriminate vinegars based on their composition of volatile components. For PLS-DA models, anal. of variance (ANOVA) or variable importance in the projection (VIP) value were used to select variables with the highest discriminatory power, and the Kennard-Stone algorithm was used to select the training and testing samples. The PLS-DA models (ANOVA or VIP) all provided a classification accuracy of 100% for the training set, and subsequent application of these models allowed the grouping of unknown samples (testing set) according to their characteristics (raw materials and processing technol.). Traditional Chinese vinegars have a long history but nowadays adulterations of them are becoming a problem in the market. In this study, Chinese fermented vinegars from different varieties were identified based on volatile composition We found that starter cultures and fermentation process have the greatest influence on the volatile components of vinegars, while the influence of raw material and steaming of raw material are weaker volatile components. Then, partial least squares-discriminant anal. models, we carried out could successfully be applied to predict unknown vinegar samples based on a database of volatile components. This study provided a strategy to detect the identity of different vinegars, which can also be used to monitor the quality and safety of traditional Chinese vinegars.

Journal of Food Biochemistry published new progress about Alcohols Role: ANT (Analyte), FFD (Food or Feed Use), ANST (Analytical Study), BIOL (Biological Study), USES (Uses). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Product Details of C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Ooi, Teng Sin published the artcileVolatile organic compounds and sensory profile of dark chocolates made with cocoa beans fermented with Pichia kudriavzevii and Hanseniaspora thailandica, Formula: C7H10N2, the main research area is volatile organic compound dark chocolate cocoa bean Pichia Hanseniaspora; Chocolate; Cocoa beans; Sensory; Volatile organic compounds; Yeast starter.

Volatile organic compounds (VOCs) are important to determine the aroma and sensory perception of cocoa. Starter cultures can modulate the volatile profile of cocoa beans during fermentation This study aimed to determine the VOCs and sensory of chocolates produced using cocoa beans fermented with yeast starters (Pichia kudriavzevii (MH979681), Hanseniaspora thailandica (MH979675) and the mixture of the two yeasts (Mix)). The VOCs of chocolates were determined by Head-Space Solid Phase Microextraction followed by Gas Chromatog.-Mass Spectrophotometry. Sensory anal. was determined by using trained panels. VOCs profiles of chocolates produced using beans fermented with HT, PK or Mix were noticeably different from Ghana and control chocolates (no starter). The addition of yeast starters during cocoa fermentation produced chocolates that were preferred by trained panels. Bitterness and astringency were the more intense flavor attributes in chocolates produced using cocoa beans added with yeast starters. The chocolate produced using cocoa beans fermented with PK was the most acidic; whereas chocolate produced using beans fermented with Mix had the sweetest taste. The addition of PK or HT is helpful in producing chocolate with a distinct flavor.

Journal of Food Science and Technology (New Delhi, India) published new progress about Alcohols Role: BSU (Biological Study, Unclassified), 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, Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Yu, Hang published the artcileEffects of Ultrasonic Processing and Oil Type on Maillard Reaction of D-Glucose and L-Alanine in Oil-in-Water Systems, Computed Properties of 14667-55-1, the main research area is oil ultrasonic Dglucose Lalanine.

This study investigated the effects of high-intensity ultrasonic processing on a Maillard reaction (MR) model system of D-glucose and L-alanine and its corresponding oil-in-water systems with canola, olive, palm, and coconut oil, resp. The MR in the water phase was significantly promoted in the olive and canola oil-MR systems with the higher depletion of reactants and the higher generation of final MR products compared with those in the oil-free-MR model system; however, the MR was suppressed in the systems of palm and coconut oils. The concentration of pyrazines with shorter side chain, e.g., 2,5-dimethylpyrazine and 2,6-dimethylpyrazine, was significantly increased in the presence of oils with a lower degree of unsaturation; meanwhile, the oils with higher degree of unsaturation suppressed the generation of the shorter side chain-pyrazines, but promoted the generation of pyrazines with a longer side chain, e.g., 2,3-diethyl-5-methylpyrazine and 3,5-diethyl-2methylpyrazine. Due to the oils undergoing ultrasonic processing at 80 °C, the oxidation of oils was significantly promoted, as reflected by a relatively low iodine value and high peroxide and p-anisidine values in the processed oils compared with those in the raw oils. On one hand, various carbonyl compounds were generated due to the lipid oxidation; meanwhile, these carbonyl compounds participated in the MR as part of intermediate MR products and subsequently generated various desired flavors. On the other hand, off-flavors coming from the oxidation of oils were also detected, which may affect the overall flavor profile of the oil-in-water MR systems.

Food and Bioprocess Technology published new progress about Autoxidation. 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

Petkevicius, Vytautas published the artcileA biocatalytic synthesis of heteroaromatic N-oxides by whole cells of Escherichia coli expressing the multicomponent, soluble di-iron monooxygenase (SDIMO) PmlABCDEF, Computed Properties of 14667-55-1, the main research area is sequence soluble di iron monooxygenase gene cluster pmlABCDEF; heteroaromatic oxide biocatalytic synthesis monooxygenase PmlABCDEF recombinant Escherichia.

Aromatic N-oxides (ArN-OX) are desirable biol. active compounds with a potential for application in pharmacy and agriculture industries. As biocatalysis is making a great impact in organic synthesis, there is still a lack of efficient and convenient enzyme-based techniques for the production of aromatic N-oxides. In this study, a recombinant soluble di-iron monooxygenase (SDIMO) PmlABCDEF overexpressed in Escherichia coli was showed to produce various aromatic N-oxides. Out of 98 tested N-heterocycles, seventy were converted to the corresponding N-oxides without any side oxidation products. This whole-cell biocatalyst showed a high activity towards pyridines, pyrazines, and pyrimidines. It was also capable of oxidizing bulky N-heterocycles with two or even three aromatic rings. Being entirely biocatalytic, our approach provides an environmentally friendly and mild method for the production of aromatic N-oxides avoiding the use of strong oxidants, organometallic catalysts, undesirable solvents, or other environment unfriendly reagents. The sequence of the p577A clone containing pmlABCDEF gene cluster was deposited in GenBank under the accession number MK037457.

Advanced Synthesis & Catalysis published new progress about DNA sequences (GenBank MK037457). 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

Liu, Feng-Liang published the artcileA practical and step-economic route to Favipiravir, Recommanded Product: 3,6-Difluoropyrazine-2-carboxamide, the main research area is favipiravir preparation.

A practical and step-economic route to Favipiravir, an antiviral drug, was developed. Favipiravir was synthesized in only six steps from 3-aminopyrazine-2-carboxylic acid with an overall yield of about 22.3%. Key intermediates Me 3-amino-6-bromopyrazine-2-carboxylate and 3,6-dichloropyrazine-2-carbonitrile were obtained in excellent purity via recrystallization from optimized solvents, which was beneficial to large-scale production In the key synthetic reaction, 3,6-dichloropyrazine-2-carbonitrile was reacted sequentially, in one pot, with KF and 30% H2O2 to give (after crystallization from 95% EtOH) favipiravir as colorless crystals, with a 60% yield for this final step of the synthesis.

Chemical Papers published new progress about. 356783-29-4 belongs to class pyrazines, name is 3,6-Difluoropyrazine-2-carboxamide, and the molecular formula is C5H3F2N3O, Recommanded Product: 3,6-Difluoropyrazine-2-carboxamide.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Guo, Qi published the artcileThe complete synthesis of favipiravir from 2-aminopyrazine, Related Products of pyrazines, the main research area is favipiravir preparation.

Favipiravir was synthesized from an inexpensive and com. available starting material, 2-aminopyrazine. The preferred route embedded within seven steps and was highlighted by the novel and efficient synthesis of 3,6-dichloropyrazine-2-carbonitrile. The intermediate 3,6-dichloropyrazine-2-carbonitrile was prepared in four successive steps which were regioselective chlorination of the pyrazine ring, bromination, Pd-catalyzed cyanation and Sandmeyer diazotization/chlorination. This protocol eliminated the hazardous POCl3 of previous synthetic methods and offered a better yield (48%) which was 1.3-fold higher than a recently published procedure. From intermediate 3,6-dichloropyrazine-2-carbonitrile, the subsequent nucleophilic fluorination, nitrile hydration and hydroxyl substitution efficiently afforded the target product. Another synthetic approach with the same starting material was also investigated to bypass the allergy-causing dichloro intermediate 3,6-dichloropyrazine-2-carbonitrile. The key step of monofluorination at the pyrazine C6 position of intermediate 6-chloro/bromo-3-aminopyrazine-2-carbonitriles and 6-chloro/bromo-3-hydroxylpyrazine-2-carbonitriles was not achieved.

Chemical Papers published new progress about. 356783-29-4 belongs to class pyrazines, name is 3,6-Difluoropyrazine-2-carboxamide, and the molecular formula is C5H3F2N3O, Related Products of pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem