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Thanksgiving traditionally means turkey; and turkey means the aromas that waft throughout the house while it鈥檚 roasting. But what鈥檚 responsible for these delicious smells?
Answer: the Maillard reaction. Discovered by French chemist Louis-Camille Maillard in 1912, the 鈥渞eaction鈥� is actually a complex series of steps that begins with the interaction between carbonyl groups of open-chain sugars and amine groups of amino acids to form N-aldosylamines. Eventually, depending on the food being heated, the sequence ends with the creation of multiple chemical entities, including many heterocyclic compounds.
These reactions occur when foodstuffs are heated to 140鈥�165 潞C. In addition to the aromas they produce, they are responsible for browning baked, grilled, or roasted foods such as breads, vegetables, and meats. Browning is accelerated in an alkaline environment.
All of which brings us back to turkey. As with other roasted meats, the Maillard reaction produces numerous compounds. Two that have been reported in the literature are 2-pentylpyridine and 2-hexylthiophene, shown here. (No systematic study of all of the Maillard products from turkey appears to have been conducted.)
So, when your host serves you delicious roasted turkey with all the fixings, please compliment her or him on an excellent helping of 2-pentylpyridine and 2-hexylthiophene.
2-Pentylpyridine hazard information
GHS classification*: flammable liquids, category 4 | |
H227鈥擟ombustible liquid | |
GHS classification: skin irritation, category 2 | |
H315鈥擟auses skin irritation聽 | ![]() |
GHS classification: serious eye irritation, category 2A | |
H319鈥擟auses serious eye irritation | ![]() |
GHS classification: specific target organ toxicity, single exposure; respiratory tract irritation, category 3 | |
H335鈥擬ay cause respiratory irritation | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals.聽.
2-Hexylthiophene聽hazard information
GHS classification: acute toxicity, oral, category 4 | |
H302鈥擧armful if swallowed | ![]() |
GHS classification: serious eye irritation, category 2A | |
H319鈥擟auses serious eye irritation | ![]() |
GHS classification: hazardous to the aquatic environment, long-term hazard, category 4 | |
H413鈥擬ay cause long-lasting harmful effects to aquatic life |
2-Pentylpyridine fast facts
CAS Reg. No. | 2294-76-0 |
Empirical formula | C10H15N |
Molar mass | 149.23 |
Appearance | Colorless to yellow liquid |
Boiing point | 206鈥�210 潞C |
Water solubility | 鈮�1 g/L (est.) |
2-Hexylthiophene fast facts
CAS Reg. No. | 18794-77-9 |
Empirical formula | C10H16S |
Molar mass | 168.30 |
Appearance | Colorless to pale yellow liquid |
Boiling point | 228鈥�230 潞C |
Water solubility | <1 g/L (est.) |

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