Tag: M.W=100-150

Li, Mengru published the artcileFormation of Volatile Heterocyclic Compounds and Open-Chain Amides of Theanine in Model Systems with Glucose, Tea Leaves, and Tea Extract under Tea-Roasting Conditions, Application of 2,3,5-Trimethylpyrazine, the main research area is volatile heterocyclic open chain amide theanine glucose tea roasting; 1-ethyl-1,5-dihydro-2H-pyrrol-2-one; Maillard reactions; N-ethylsuccinimide; pyrazines; tea roasting; theanine.

Theanine is a non-proteinogenic amino acid found in the tea plant Camellia sinensis. At an elevated temperature (>90 °C), it released two major volatile compounds 1-ethyl-1,5-dihydro-2H-pyrrol-2-one and N-ethylsuccinimide. Other products were identified, including 10 pyrroles and 12 amides/imides. The formation of the two major compounds was proposed to be initiated by the deamination of theanine and through the intermediate α-keto acid. In the presence of glucose, the two major products and many other volatiles from theanine thermal degradation were accelerated and further Maillard reactions occurred. A total of 56 compounds were identified in the model system of theanine and glucose, including 12 amides/imides, 16 pyrazines, 16 pyrroles and other N-heterocycles, and 12 furans and other O-heterocycles. Although most of the reaction products were detected in tea leaves and in their aqueous extract with or without the addition of theanine under the same experiment conditions, imides and amides were considerably suppressed, left only minute amounts, or were even no longer detectable. Pyrazines and pyrroles were also shown at reduced concentrations as a result of the interaction with tea components but to a lesser extent. A total of 16 and 12 pyrazines were identified in the theanine/glucose reaction system and tea leaves/aqueous extract after roasting, resp. The results indicated that pyrazines and other main volatiles in roasted tea leaves were formed from the Maillard reactions of the aqueous fraction of tea leaves. Theanine participated in the formation of pyrazines in tea leaves under roasting conditions.

Journal of Agricultural and Food Chemistry published new progress about Camellia sinensis. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Wang, Jing published the artcileDecoding the Specific Roasty Aroma Wuyi Rock Tea (Camellia sinensis: Dahongpao) by the Sensomics Approach, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is roasty aroma Wuyi rock tea; Dahongpao; aroma recombination; odor activity values; pyrazines; roasty aroma.

Aroma extract dilution anal. was performed on volatile fractions extracted from a freshly prepared Dahongpao (DHP) tea infusion using solvent-assisted flavor evaporation, yielding 65 odor-active domains with flavor dilution factors ranging between 32 and 32,768. In addition, six aromatic substances were captured by headspace anal. Quantitation of 54 compounds by an internal standard method and stable isotope dilution assays revealed that the concentrations of 32 odorants exceeded their resp. orthonasal odor threshold values in tea infusion. The results of odor activity values (OAVs) suggested that 2-metylbutanal (malty) and γ-hexalactone (coconut-like) had the highest OAVs (248 and 154). Eight odorants including γ-hexalactone (OAV 154), Me 2-methylbutanoate (59), phenylacetic acid (7.2), acetylpyrazine (5.7), 2-methoxyphenol (3.4), p-cresol (2.7), 2,6-diethylpyrazine (2.7), and vanillin (1.8) were newly identified as key odorants in DHP tea infusion. An aroma recombination model in a non-volatile matrix extracted from tea infusion satisfactorily mimicked the overall aroma of DHP tea infusion, thereby confirming the identification and quant. experiments Omission experiments verified the obvious significance of 6-methyl-5-hepten-2-one (OAV 91), 2-ethyl-3,5-dimethylpyrazine (19), 4-hydroxy-2,5-dimethylfuran-3(2H)-one (13), and acetylpyrazine (5.7) as key odorants for the special roasty and caramel-like aroma of DHP tea.

Journal of Agricultural and Food Chemistry published new progress about Camellia sinensis. 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

Bofill, Lidia published the artcileA Novel, Extremely Bioavailable Cocrystal of Pterostilbene, Category: pyrazines, the main research area is bioavailable cocrystal pterostilbene nutraceutical crystal engineering.

New multicomponent solid forms of the nutraceutical pterostilbene have been discovered and characterized through exptl. cocrystal screening. Among the coformers tested, picolinic acid formed a cocrystal with a 10-fold enhancement of oral bioavailability in rats, which converts the new cocrystal into a very promising candidate for new formulations of pterostilbene with improved performance.

Crystal Growth & Design published new progress about Cocrystallization. 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

Zhu, Wenhui published the artcileFlavor characteristics of shrimp sauces with different fermentation and storage time, Safety of 2,3,5-Trimethylpyrazine, the main research area is Acetes sauce flavor volatile compound fermentation storage time.

The present study investigated the volatile compounds in nearly three-year shrimp sauces and the effects of different fermentation and storage time on the integral aroma characteristics. The 89 volatile compounds were identified by solid phase microextraction (SPME) and gas chromatog.-mass spectrometry (GC-MS) anal. Compared with the other two samples, the shrimp sauces which fermented and storage for 2 years has the highest umami amino acid content and the better flavor. The results of electronic nose (e-nose) and electronic tongue (e-tongue) detection to distinguish the aroma characteristics of different samples demonstrated good agreement with those obtained by GC-MS anal. These results suggested that proper fermentation and storage time are critical to the flavor quality of shrimp sauces.

LWT–Food Science and Technology published new progress about Acetes chinensis. 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

Yang, Huilin published the artcileExploring functional core bacteria in fermentation of a traditional Chinese food, Aspergillus-type douchi, Synthetic Route of 14667-55-1, the main research area is Aspergillus douche traditional Chinese food fermentation bacteria.

Douchi is a type of traditional Chinese flavoring food that has been used for thousands of years and is produced by multispecies solid-state fermentation However, the correlation between the flavor, the microbiota, and the functional core microbiota in Aspergillus-type douchi fermentation remains unclear. In this study, Illumina MiSeq sequencing and chromatog. were used to investigate the bacterial community and flavor components in Aspergillus-type douchi fermentation The dominant phyla were Firmicutes, Proteobacteria, and Actinobacteria, and the dominant genera were Weissella, Bacillus, Anaerosalibacter, Lactobacillus, Staphylococcus, and Enterococcus. A total of 58 flavor components were detected during fermentation, including two alcs., 14 esters, five pyrazines, three alkanes, four aldehydes, three phenols, six acids, and five other compounds Bidirectional orthogonal partial least square modeling showed that Corynebacterium_1, Lactococcus, Atopostipes, Peptostreptococcus, norank_o__AKYG1722, Truepera, Gulosibacter, norank_f__Actinomycetaceae, and unclassified_f__Rhodobacteraceae are the functional core microbiota responsible for the formation of the flavor components during douchi fermentation This is the first study to investigate the functional core microbiota in douchi fermentation using Illumina MiSeq sequencing and chromatog. techniques. Our findings extend our understanding of the relationships between flavor, the microbiota, and the functional core microbiota during Aspergillus-type douchi fermentation

PLoS One published new progress about Actinomycetaceae. 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

Shen, Dong-Yu published the artcileCharacterization of aroma in response surface optimized no-salt bovine bone protein extract by switchable GC/GCxGC-olfactometry-mass spectrometry, electronic nose, and sensory evaluation, HPLC of Formula: 14667-55-1, the main research area is bovine bone protein extract aroma GC olfactometry mass spectrometry.

No-salt bovine bone protein extract (NS-BBPE) is rich in bone collagen, peptides and amino acids and is useful in the food industry. However, NS-BBPE has a more monotonous taste than bovine bone protein extract (BBPE), so BBPE is more useful than NS-BBPE. According to the World Health Organization, adults who eat less than 6 g/d have improved health. Odor-induced saltiness (OISE) is a way to reduce the amount of NaCl in food. The multisensory interaction between aroma (meaty and roasted) and taste can be used to compensate for the saltiness perception of healthy low-salt food. In this study, the optimal Maillard conditions from response surface optimization were as follows: temperature, 105°C; time, 20 min; reducing sugar addition, 1 g; EH-NS-BBPE, 30 g; water, 10 g; hydrolyzed vegetable protein (HVP), 5 g; bovine tallow, 3 g; L-Cys, 0.5 g; cysteine hydrochloride, 1 g; VB1, 0.4 g; and I+G, 0.5 g. The salt-congruent aroma was produced from the Maillard reaction products of NS-BBPE, which was detected by a new SGC/GC2-O-MS system. Electronic nose anal. of the difference in aroma and sensory evaluation proved that salt-congruent aroma was present in the samples.

LWT–Food Science and Technology published new progress about Adult, mammalian. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, HPLC of Formula: 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Luo, Kathleen K. published the artcileInfluence of post-harvest moisture on roasted almond shelf life and consumer acceptance, Safety of 2,3,5-Trimethylpyrazine, the main research area is Prunus roasted mech drying storage quality moisture shelf life; HS-SPME GC/MS; almond; descriptive analysis; moisture; sensory; shelf-life.

BACKGROUND : The harvest weights of sweet almonds (Prunus dulcis) have significantly increased to meet consumer demand and now exceed processing facility capabilities. Crops are stockpiled for longer periods, increasing the probability of moisture exposure. Wet almonds can be mech. dried prior to processing; however, it is unclear how this practice influences lipid oxidation, shelf-life, and consumer acceptance. To address this, almonds were exposed to 8% moisture and dried with low heat (ME). Almonds were roasted and stored under accelerated conditions for 12 mo and markers of lipid oxidation, headspace volatiles, sensory attributes, and consumer liking were evaluated. RESULTS : At 7 mo of storage, light roast ME almonds had higher levels of volatiles related to lipid oxidation than non-moisture exposed almonds (NME) and were significantly higher in oxidized, cardboard and painty / solvent flavors. Although untrained consumers did not show significant preferences between the light roast ME and NME almonds, there were quality losses related to lipid oxidation that trained panelists could detect. Dark roast ME almonds demonstrated significant lipid oxidation by 5 mo of storage, indicating they will have a compromised shelf life. Findings also indicate that octanal, nonanal, 2-octenal, and hexanoic acid are good indicators of consumer acceptability. CONCLUSION : The results of this research illustrate that post-harvest moisture exposure with mech. drying has a significant effect on the storage quality of roasted almonds and is most pronounced in dark roast products.

Journal of the Science of Food and Agriculture published new progress about Almond (roasted). 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

Xu, Yuanrong published the artcilePhysicochemical quality and volatile flavor compounds of hot air-assisted radio frequency roasted almonds, Synthetic Route of 14667-55-1, the main research area is roasted almond physicochem quality volatile flavor compound.

This study applied hot air-assisted radio frequency (HA-RF) as a new roasting method for almonds. Almonds roasted by HA-RF at medium level (120-130°C, 15 min) had best quality compared with that roasted at light (110-120°C, 10 min) or heavy (120-130°C, 20 min) level. After medium level HA-RF roasting, moisture content of almonds decreased to 3.4% from initially 4.2%, acid value and peroxide value of HA-RF roasted almonds were significantly (p < .05) lower than those roasted by conventional oven. There were 61 and 87 volatile compounds in raw and HA-RF roasted almonds, resp., and 21 new volatile compounds were generated after storage of 18 wk. Sensory attributes of HA-RF roasted almonds were in well acceptable range and overall consumer acceptance (8.3) was comparable with that of oven roasted almonds (8.0). This study applied HA-RF heating as a novel roasting method for almonds, research findings in this study indicated that HA-RF roasting obtained good physicochem. and sensory quality of almonds when compared with conventional oven roasting, and HA-RF roasting could obtain desired roasted flavor compounds Due to rapid and volumetric heating characteristics of RF heating, HA-RF roasting had high roasting efficiency and could obtain desired sample texture and flavor with low roasting temperature And HA-RF roasting is easily scale-up for com. application, thus HA-RF holds great potential as an industrial roasting method for almonds. Journal of Food Processing and Preservation published new progress about Almond (roasted). 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

Wang, Haili published the artcileCharacterization of key odor-active compounds in thermal reaction beef flavoring by SGCxGC-O-MS, AEDA, DHDA, OAV and quantitative measurements, Product Details of C7H10N2, the main research area is furanthiol methylbutanal beef flavoring extraction mass spectrometry gas chromatog.

Thermal reaction beef flavoring is a kind of food additive. In this study, three extraction methods of dynamic headspace sampling (DHS), solid phase micro-extraction (SPME) and liquid-liquid extraction (LLE) combined with switchable two-dimensional gas chromatog.-olfactometry-mass spectrometry (SGCxGC-O-MS) were employed to characterize volatile compounds in thermal reaction beef flavoring. The odor characteristics of thermal reaction beef flavors were identified by sensory evaluation, aroma extraction dilution anal. (AEDA), dynamic headspace dilution anal. (DHDA), odor activity value (OAV) and quant. measurements. A total of 231 volatile odor compounds were identified by the three extraction methods, which including 15 aldehydes, 41 ketones, 29 alcs., 27 esters, 13 furans, 20 pyrazines, 9 sulfur-containing compounds, 18 thiophenes and thiazoles, 19 acids and 40 other compounds Ninety-eight compounds had odor activity, and 22 odor-active compounds were quant. analyzed. 2-Methyl-3-furanthiol (meaty) and bis(2-methyl-3-furanyl) disulfide (onion) had the higher FD and OAV, 3-methylbutanal (chocolate) was first identified as the key odor-active compound in thermal reaction beef flavoring, Me furfuryl disulfide (meaty), 2-ethyl-3,5-dimethylpyrazine (roasted nuts), 2,3-butanedione (caramel), linalool (floral), furfural (baked bread), 2-furfurylthiol (sulfury) and other compounds were also identified as the key aroma components in thermal reaction beef flavoring. The results showed that SPME and DHS were more suitable than LLE for the separation and extraction of volatile odor compounds in thermal reaction beef flavoring, and there were some masking and synergistic effects between odor-active compounds

Journal of Food Composition and Analysis published new progress about Beef (flavoring). 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

Rigling, Marina published the artcileApplication of a direct immersion-stir bar sorptive extraction (DI-SBSE) combined GC-MS method for fingerprinting alkylpyrazines in tea and tea-like infusions, Name: 2,3,5-Trimethylpyrazine, the main research area is alkylpyrazine tea infusion stir bar sorptive extraction.

A series of alkylpyrazines, contributing to the overall flavor, are described in tea and tea infusions. Their low concentrations and moderate water solubility are facing anal. trouble when it comes to typical applied headspace analyses. Accordingly, a stir bar sorptive extraction methodol. (SBSE) was established. It was found that immersion-based techniques (direct-immersion SBSE (DI-SBSE) and multiple SBSE (mSBSE)) showed higher extraction efficiency compared to headspace sorptive extraction (HSSE). In the end, a DI-SBSE methodol. was established with a calibration range of 0.1-50μg/L for six alkylpyrazines to systematically quantify their presence in tea and tea-like infusions. With determined LOQs between 21 and 118 ng/L, the method was sensitive enough to detect the expected low amounts Application of the established DI-SBSE methodol. for six alkylpyrazines in seven green, three white, one oolong, two black teas, as well as two tea-like infusions (nettle and raspberry leaf) revealed great variations in total concentration of alkylpyrazines between 0.36 ± 0.05μg/L (raspberry leaf) and 24.20 ± 0.41μg/L (oolong tea). Furthermore, concentration levels in between the same tea type ranged drastically, with 14.19 ± 0.62μg/L for Longjing green tea and 0.74 ± 0.02μg/L for Warwick green tea. Most abundant alkylpyrazines in the samples were 2-methylpyrazine and 2,5-dimethylpyrazine. Overall good similarities in compositional distribution of alkylpyrazines in the same tea type and strong correlations of the alkylpyrazines over all types indicating distinct fingerprints being present and the types are differentiable based on their alkylpyrazine pattern.

European Food Research and Technology published new progress about Black tea leaves. 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