Alkylpyrazine

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Alkylpyrazines are chemical compounds based on pyrazine with different substitution patterns. Some alkylpyrazines are naturally occurring highly aromatic substances which often have a very low odor threshold [1] and contribute to the taste and aroma of various foods including cocoa, baked goods, coffee and wines. [2] [3] Alkylpyrazines are also formed during the cooking of some foods via Maillard reactions. [1]

Contents

Examples

2-Methylpyrazine

2-Methylpyrazine was the volatile odorant found at the highest concentration in roasted sesame seed oil. [4]

2,3-Dimethylpyrazine

2,3-Dimethylpyrazine is a component of the aroma of roasted sesame seeds. [4]

2,5-Dimethylpyrazine

2,5-Dimethylpyrazine is used as flavor additive and odorant in foods such as cereals [5] and products such as cigarettes. It occurs naturally in asparagus, black or green tea, crispbread, malt, raw shrimp, soya, squid, Swiss cheeses, and wheat bread. [5] It's also found in roasted sesame. [4] The chemical formula is C6H8N2. [5]

2,6-Dimethylpyrazine

2,6-Dimethylpyrazine is also used as flavor additive and odorant in foods such as cereals [6] and products such as cigarettes. It occurs naturally in baked potato, black or green tea, crispbread, French fries, malt, peated malt, raw asparagus, roasted barley, roasted filberts or pecans, squid, wheat bread, wild rice (Zizania aquatica), and wort. [6] It's also found in roasted sesame. [4] The chemical formula is C6H8N2. [6]

2,3,5,6-Tetramethylpyrazine

Tetramethylpyrazine (ligustrazine) is found in nattō and in fermented cocoa beans. [7]

See also

Related Research Articles

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<span class="mw-page-title-main">Maillard reaction</span> Chemical reaction in cooking

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<span class="mw-page-title-main">Tetramethylpyrazine</span> Chemical compound

Tetramethylpyrazine, also known as ligustrazine, is a chemical compound found in nattō and in fermented cocoa beans. In an observational study, tetramethylpyrazine was the dominant volatile organic compound in one sourdough starter. When purified, tetramethylpyrazine is a colorless solid. It is classified as an alkylpyrazine. Its biosynthesis involves amination of acetoin, the latter derived from pyruvate. It exhibits potential nootropic and antiinflammatory activities in rats.

<span class="mw-page-title-main">Methional</span> Chemical compound

Methional is an organic compound with the formula CH3SCH2CH2CHO. It is a colorless liquid that is a degradation product of methionine. It is a notable flavor in potato-based snacks, namely potato chips, one of the most popular foods containing methional. Traces of the compound can also be found in black tea and green tea based products. Methional contains both aldehyde and thioether functional groups. It is readily soluble in alcohol solvents, including propylene glycol and dipropylene glycol.

<span class="mw-page-title-main">3-Isobutyl-2-methoxypyrazine</span> Chemical compound

3-Isobutyl-2-methoxypyrazine is a methoxypyrazine that is very similar to isopropyl methoxy pyrazine except that the alkyl side-group contains an isobutyl group attached to the carbon alpha to the methoxy sidegroup instead of an isopropyl side-group at that same carbon position.

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References

  1. 1 2 Susan M. Fors; Bertil K. Olofsson (1985). "Alkylpyrazines, volatiles formed in the Maillard reaction. I. Determination of odour detection thresholds and odour intensity functions by dynamic olfactometry". Chemical Senses. 10 (3): 287–296. doi:10.1093/chemse/10.3.287.
  2. Zhao, Chao; Cao, Hui; Xiao, Jianbo (2020). "Pyrazines in Food". Handbook of Dietary Phytochemicals. Springer: 1–25. doi: 10.1007/978-981-13-1745-3_44-1 . ISBN   978-981-13-1745-3.
  3. Mihara, Satoru; Masuda, Hideki (1988). "Structure-odor relationships for disubstituted pyrazines". Journal of Agricultural and Food Chemistry. 36 (6): 1242–7. doi:10.1021/jf00084a029.
  4. 1 2 3 4 Shimoda, M.; Shiratsuchi, H.; Nakada, Y.; Wu, Y.; Osajima, Y. (1996). "Identification and Sensory Characterization of Volatile Flavor Compounds in Sesame Seed Oil". Journal of Agricultural and Food Chemistry. 44 (12): 3909–3912. doi:10.1021/jf960115f.
  5. 1 2 3 "2,5-DIMETHYLPYRAZINE". PubChem Compound Database; CID=31252. National Center for Biotechnology Information. Retrieved 2017-01-21.
  6. 1 2 3 "2,6-DIMETHYLPYRAZINE". PubChem Compound Database; CID=7938. National Center for Biotechnology Information. Retrieved 2017-01-21.
  7. Effect of mass and turning time on free amino acid, peptide-N, sugar and pyrazine concentration during cocoa fermentation. P Hashim, J Selamat, S Muhammad, S Kharidah and A Ali, Journal of the Science of Food and Agriculture, 1998, Volume 78, pages 543–550. doi : 10.1002/(SICI)1097-0010(199812)78:4<543::AID-JSFA152>3.0.CO;2-2