Category: Pyrazines

Sioriki, Eleni published the artcileImpact of alkalization conditions on the phytochemical content of cocoa powder and the aroma of cocoa drinks, Formula: C7H10N2, the main research area is cocoa powder aroma drink alkalization phytochem content.

Alkalization is an important process in cocoa powder production that affects color and flavor. In this study, the impact of alkalization temperature (60, 70, 80, 90, 100°C), NaOH concentration (0.59, 1.17, 2.34, 3.59% weight/weight of cocoa powder) and alkalization time (1 and 10 min) on the physicochem. properties (pH, color) and phytochem. profile (theobromine, caffeine, epicatechin, catechin) of cocoa powder were investigated, while the aroma was studied on the corresponding cocoa drinks. High-performance liquid chromatog. coupled to an ultra-violet detector (HPLC-UV) was used for screening the non-volatiles and headspace solid – phase microextraction – gas chromatog. – mass spectrometry (HS-SPME-GC-MS) for the aromatic compounds Major changes of the cocoa properties occurred during the first minute of alkalization. Increase of temperature and alkali concentration generally reduced the levels of epicatechin and the lightness (L*), while the pH of the cocoa powder was affected by changing the alkali concentration On the other hand, the reddish (a*) and yellowish (b*) color component values and theobromine levels were not significantly affected by varying temperature and alkali concentration A higher temperature did not affect the concentration of the volatile compounds, while a decrease in certain chem. classes was observed by increasing the alkali concentration

LWT–Food Science and Technology published new progress about Aldehydes Role: ANT (Analyte), BSU (Biological Study, Unclassified), ANST (Analytical Study), 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

Yin, Wen-ting published the artcileChanges in key aroma-active compounds and sensory characteristics of sunflower oils induced by seed roasting, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is sunflower oil seed roasting aromatic compound sensory property olfactometry; gas chromatography-olfactometry-mass spectrometry; molecular sensory science; odor; odor active value; oil processing.

This study investigated the changes in aroma composition and perception of sunflower oils induced by seed roasting using sensory-oriented flavor anal. Volatile compounds were extracted by solvent-assisted flavor evaporation and headspace solid-phase microextraction Odorants were characterized by gas chromatog.-olfactometry-mass spectrometry and aroma extract dilution anal. The cold-pressed and roasted sunflower oils contained 13 and 50 odorants, resp., with the flavor dilution factors between 1 and 256. Fifty-six odorants were newly identified in sunflower oils. Quantification of 26 important odorants by the external standard method revealed apparent changes induced by seed roasting in loss of terpenes, formation of Maillard reaction products, and the increase in lipid oxidation products. The most important odorants (odor active values, OAVs = 1-1857) in the cold-pressed sunflower oil included α-pinene (11,145 μg/kg), β-pinene (4068 μg/kg), linalool (56 μg/kg), hexanal (541 μg/kg), octanal (125 μg/kg), α-phellandrene (36 μg/kg), and (E)-2-octenal (69 μg/kg), contributing to the raw sunflower seed, woody, green, earthy, and sweet aromas of the oil. The most important contributors (OAVs = 1-884) to the roasted, smoky, and burnt aromas of the roasted sunflower oil were 2- and 3-methylbutanal (6726 and 714 μg/kg), 2,6-dimethylpyrazine (2329 μg/kg), 2,5-dimethylpyrazine (12,228 μg/kg), 2,3-dimethylpyrazine (238 μg/kg), 2,3-pentanedione (1456 μg/kg), 2-pentylfuran (1332 μg/kg), 2,3-dimethyl-5-ethylpyrazine (213 μg/kg), and 1-pentanol (693 μg/kg). Aroma recombination of the key odorants in odorless sunflower oil adequately mimicked the general aroma profiles of sunflower oils. This study provides an important foundation for understanding the relationship between oil processing and aroma mols. of sunflower oils. The clear changes observed in the composition and concentrations of key aroma compounds explained the changes in sensory characteristics of sunflower seed oils induced by seed roasting on a mol. basis. Characterizing the key aroma-active composition of sunflower oil and investigating its relationship with oil processing could provide important practical applications for the sunflower oil industry in flavor regulation, quality control, product development, and process optimization.

Journal of Food Science published new progress about Aldehydes Role: ANT (Analyte), BSU (Biological Study, Unclassified), ANST (Analytical Study), BIOL (Biological Study). 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

Zhang, Youfeng published the artcileDetermination of Origin of Commercial Flavored Rapeseed Oil by the Pattern of Volatile Compounds Obtained via GC-MS and Flash GC Electronic Nose, Safety of 2,3,5-Trimethylpyrazine, the main research area is rapeseed oil Gas chromatog mass spectroscopy volatile compound determination.

Flavored rapeseed oil (FRO) is a typical hot-pressed oil and is widely consumed in China due to its strong characteristic flavor and intensive color. In this study, volatile profiles of 33 representative com. rapeseed oils in China are characterized by gas chromatog.-mass spectrometry (GC-MS) and flash gas chromatog. (GC) electronic nose system. A 51 volatile compounds are identified and the nitriles (methallyl cyanide and 5-cyano-1-pentene), aldehydes (nonanal, 3-furaldehyde, and 5-methyl-2-furancarboxaldehyde), alcs. (1,5-hexadien-3-ol, 2-furanmethanol, and phenylethyl alc.), and pyrazines (2,5-dimethyl-pyrazine and 2,6-dimethyl-pyrazine) are the major volatile compounds in FROs. Glucosinolate degradation products account for the highest proportion of these volatiles, which are found to have a pos. correlation with the erucic acid content (R2 = 0.796, p < 0.01). FRO from Sichuan province in the southwest of China can be characterized by the obvious distinctions in flash GC electronic nose combined with principal component anal., which indicates that the flash GC electronic nose can be used as a promising method to identify the origins of FRO. This work is helpful for expanding the knowledge of volatiles of com. flavored rapeseed oil. The data can also serve as a basis for the quality assessment of hot-pressed rapeseed oil. Meanwhile, the flash GC electronic nose combined with principal component anal. can be used as a promising method for the classification of flavor rapeseed oil production areas. European Journal of Lipid Science and Technology published new progress about Aldehydes Role: ANT (Analyte), BSU (Biological Study, Unclassified), ANST (Analytical Study), BIOL (Biological Study). 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

Dai, Chunhua published the artcileEffect of solid-state fermentation by three different Bacillus species on composition and protein structure of soybean meal, COA of Formula: C7H10N2, the main research area is Bacillus Geobacillus solid state fermentation soybean meal; Bacillus species; fermentation; ingredient; protein structure; soybean meal.

Fermentation efficiency of thermophiles of Bacillus licheniformis YYC4 and Geobacillus stearothermophilus A75, and mesophilic Bacillus subtilis 10 160 on soybean meal (SBM), was evaluated by examining the nutritional and protein structural changes. SBM fermentation by B. licheniformis YYC4, B. subtilis 10 160 and G. stearothemophilus A75 increased significantly the crude and soluble protein from 442.4 to 524.8, 516.1 and 499.9 g kg-1, and from 53.9 to 203.3, 291.3 and 74.6 g kg-1, and decreased trypsin inhibitor from 8.19 to 3.19, 2.14 and 5.10 mg g-1, resp. Bacillus licheniformis YYC4 and B. subtilis 10 160 significantly increased phenol and pyrazine content. Furthermore, B. licheniformis YYC4 fermentation could produce abundant alcs., ketones, esters and acids. Surface hydrophobicity, sulfhydryl groups and disulfide bond contents of SBM protein were increased significantly from 98.27 to 166.13, 173.27 and 150.71, from 3.26 to 4.88, 5.03 and 4.21μmol g-1, and from 20.77 to 27.95, 29.53 and 25.5μmol g-1 after their fermentation Fermentation induced red shifts of the maximum absorption wavelength (λmax) of fluorescence spectra from 353 to 362, 376 and 361 nm, while significantly reducing the fluorescence intensity of protein, especially when B. subtilis 10 160 was used. Moreover, fermentation markedly changed the secondary structure composition of SBM protein. Analyses by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and at. force microscopy showed that macromol. protein was degraded into small-sized protein or peptide during fermentation of SBM. Bacillus licheniformis YYC4 fermentation (without sterilization) improved nutrition and protein structure of SBM as B. subtilis 10 160, suggesting its potential application in the SBM fermentation industry. 2021 Society of Chem. Industry.

Journal of the Science of Food and Agriculture published new progress about Bacillus licheniformis. 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

Zhou, Jiadi published the artcileδ-Regioselective heteroarylation of free alcohols through 1,5-hydrogen-atom transfer, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is heteroarene alkyl alc silver catalyst regioselective heteroarylation; alkyl heteroarene preparation.

An efficient silver-catalyzed δ-regioselective C(sp3)-H heteroarylation of free alcs. was developed. Various alcs. reacted with quinolines, isoquinoline, pyridines, pyrimidine, phthalazine, 4-hydroxyquinazoline, acridine, quinoxaline and pyrazine to give the corresponding C(sp2)-H alkylation products in 31-89% yields. Notably, all types (1°, 2°, and 3°) of δ-C(sp3)-H bonds in the alcs. was regioselectively activated. This protocol provided a platform to access divergent functionalizations of alcs. and heteroaryls by forming the challenging δ-selective C(sp3)-C(sp2) bond.

Organic Chemistry Frontiers published new progress about Aromatic nitrogen heterocycles Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 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

Rocchetti, Gabriele published the artcileIdentification of markers of sensory quality in ground coffee: an untargeted metabolomics approach, Product Details of C7H10N2, the main research area is ground coffee sensory quality marker metabolomic approach; Food quality; Food volatiles; HS-GC-MS; Metabolomics; Sensory markers; UHPLC-QTOF-MS.

In the last years, consumers increased the demand for high-quality and healthy beverages, including coffee. To date, among the techniques potentially available to determine the overall quality of coffee beverages, metabolomics is emerging as a valuable tool. In this study, 47 ground coffee samples were selected during the 2018 Edition of the “”International coffee tasting”” (ICT) in order to provide discrimination based on both chem. and sensory profiles. In particular, 20 samples received a gold medal (“”high quality”” group), while lower sensory scores characterized 27 samples (without medal). Untargeted metabolomics based on ultra-high pressure liquid chromatog. coupled with quadrupole-time-of-flight (UHPLC-QTOF) and head space-gas chromatog. coupled with mass spectrometry platforms followed by multivariate statistical approaches (i.e., both supervised and unsupervised) were used to provide new insight into the searching of potential markers of sensory quality. Several compounds were identified, including polyphenols, alkaloids, diazines, and Maillard reaction products. Also, the headspace/GC-MS highlighted the most important volatile compounds Polyphenols were scarcely correlated to the sensory parameters, while the OPLS-DA models built using typical coffee metabolites and volatile/Maillard compounds possessed prediction values > 0.7. The “”high quality”” group showed specific metabolomic signatures, thus corroborating the results from the sensory anal. Overall, Me pentanoate (ROC value = 0.78), 2-furfurylthiol (ROC value = 0.75), and L-Homoserine (ROC value = 0.74) established the higher number of significant (p < 0.05) correlations with the sensory parameters. Although ad-hoc studies are advisable to further confirm the proposed markers, this study demonstrates the suitability of untargeted metabolomics for evaluating coffee quality and the potential correlations with the sensory attributes. Metabolomics published new progress about Carboxylic acids 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

Rajhi, Imene published the artcileHS-SPME-GC-MS characterization of volatile chemicals released from microwaving and conventional processing methods of fenugreek seeds and flours, COA of Formula: C7H10N2, the main research area is fenugreek seed flour volatile chem microwaving HS SPME GCMS.

This study was to evaluate the effects of microwave and conventional processing methods on the aroma profiles of fenugreek seeds and flours. The volatiles of raw, sprouted, boiled, roasted, and micro-waved fenugreek grains were evaluated using headspace-solid phase micro-extraction (HS-SPME) coupled to gas chromatog.-mass spectrometry (GC-MS). 51 and 60 volatiles were detected in the emission bouquets of raw and processed seeds and flours, resp. Volatiles were divided into seven chem. classes, including monoterpenes hydrocarbons, sesquiterpenes hydrocarbons, phenylpropanoids, non-terpenes derivatives, apocarotenes, nitrogen/sulfur derivative and oxygenated monoterpenes. The data showed that volatiles were significantly affected by the type of processing. All treatments increase the amounts of volatiles including aldehydes, alcs., esters, and alkanes except for the microwave heating. Indeed, the dominant volatiles in microwaved fenugreek were pyrazines, with chocolate aroma like flavor. The microwave heating is based on an energy-efficient and water-saving technol.; it is an interesting and more sustainable technique to be employed in the legume processing. The findings of this study demonstrate that microwave technol. has potential for fenugreek processing.

Industrial Crops and Products published new progress about Aldehydes 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

Sun, Xuelian published the artcileChanges in the volatile profile, fatty acid composition and oxidative stability of flaxseed oil during heating at different temperatures, Application In Synthesis of 14667-55-1, the main research area is flaxseed oil heating volatile fatty acid oxidative stability temperature.

The deterioration of flaxseed oil (FSO) during heating greatly influences the quality of fried foods. FSOs heated at different temperatures (120 °C, 150 °C, 180 °C, and 210 °C) were investigated for volatile organic compound (VOC) and fatty acid compositions and physicochem. indexes. In total, 84 VOCs were identified, including 20 aldehydes (37.43%-66.17%), 20 alcs. (31.19%-42.90%), 9 esters (0.28%-1.27%), 8 ketones (0.4%-1.58%), 19 alkanes (1.15%-19.96%), and 8 heterocyclics (0.68%-6.16%). Furthermore, 1-nonanal, 2,4-decadienal, hexanal, and trans,trans-2,4-heptadienal were identified as the characteristic aroma compounds to estimate the oxidation degree of heated FSO through the calculation of odor activity values. The polyunsaturated fatty acid content in FSO significantly (p < 0.05) decreased by 5.75 μg/g after heating at 210 °C. The physicochem. indexes of FSO increased during heating with acid, peroxide, p-anisidine and thiobarbituric acid values ranging from 0.26 to 0.55 mg NaOH/g, 0.041-0.066 g/100 g, 0.12-0.88, and 0.025-0.088, resp. Results of Pearson correlation anal. indicate that 2,4-decadienal and hexanal may be oxidation deterioration markers in FSO. This study provides a theor. basis for evaluation of the suitability of FSO for household food preparation LWT--Food Science and Technology published new progress about Aldehydes 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, Application In Synthesis of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Gao, Peng published the artcileAnalysis of the non-volatile components and volatile compounds of hydrolysates derived from unmatured cheese curd hydrolysis by different enzymes, Synthetic Route of 14667-55-1, the main research area is cheese curd enzymic hydrolysis hydrolyzate nonvolatile volatile component analysis.

Fifteen cheese protein hydrolyzates were produced by using four different proteases. Then, the free amino acids (FAAs), mol. weight distribution (MWD), electronic tongue evaluation, and volatile compounds of the corresponding products were evaluated, resp. The results suggested that 2SD had the strongest hydrolysis characteristic, followed by 6SD and FN. Samples hydrolyzed for less than 6 h or more than 18 h contained great defects of taste. Peptides with 150 Da-450 Da were mainly responsible for bitterness, saltiness, umami, and aftertaste in some enzyme hydrolysis. Under the same total enzyme concentration condition, the sample hydrolyzed by Flavorzyme and Neutrase for 18 h released more richness and less bitterness than the other systems, which were characterized by butter and cream odor. Notably, it was found for the first time that tetramethylpyrazine (TMP) was detected in cheese proteolysis with the highest content of 17.59μg/g in Protease 2SD for 30 h. 2-Undecanone and acetoin played a key role in the flavor formation of the tested samples. Regarding the different chem. families of volatiles, acids were more abundant in the samples hydrolyzed by Protease 2SD and 6SD, while FN systems can achieve high ketone content.

LWT–Food Science and Technology published new progress about Aldehydes 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, Synthetic Route of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Mildner-Szkudlarz, Sylwia published the artcileChanges in volatile compound profiles of cold-pressed berry seed oils induced by roasting, Category: pyrazines, the main research area is berry seed oil volatile compound cold pressing roasting.

This study aimed to compare the volatile compounds of cold-pressed oils obtained from unroasted and roasted chokeberry, raspberry, blackcurrant, and strawberry seeds using comprehensive gas chromatog.-mass spectrometry coupled to time of flight mass spectrometry (GC x GC-ToFMS). It is found that the seed type used and chem. composition affected the final aroma of berry oils. The volatile profiles of all berry oils from both unroasted and roasted seeds were dominated by nonheterocyclic chem. class (89% of the total volatiles) with esters predominant (32% of total nonheterocyclic compounds). Unroasted raspberry and blackcurrant cold-pressed seed oils had a less complex volatile profile, and showed similarities between them and differences to chokeberry and strawberry seed oils. Chokeberry seed oil was characterized by the highest levels in Et propanoate, methylbutyl acetate, benzaldehyde, (E,E)-2,4-decadienal, acetoin, 3-penten-2-one, benzyl alc. and strawberry seed oil by Me acetate, iso-Bu acetate, Me 2-methylbutanoate, Et 2-hydroxypropanoate, Et 2-methylbutanoate, Et 3-methylbutanoate, (E,E)-2,4-heptadienal, 1-penten-3-one, and 3,7-dimethyl-1,6-octadien-3-ol. N-containing and furanic-containing compounds contributed about 5% and 4%-16%, resp., of total amount of volatiles after seed roasting. Roasting was critical for increasing the concentration of compounds derived from lipid peroxidation, especially in blackcurrant seed oils. Profiling volatiles using SPME-GC x GC-ToFMS might be helpful in evaluating oils quality.

LWT–Food Science and Technology published new progress about Aldehydes 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, Category: pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem