2-Nonenal
[CAS# 2463-53-8]

Identification

• Classification: Flavors and spices >> Synthetic spice >> Aldehyde fragrance >> Acyclic aliphatic aldehyde
• Name: 2-Nonenal
• Synonyms: (E)-non-2-enal
• Molecular Formula: C₉H₁₆O
• Molecular Weight: 140.22
• CAS Registry Number: 2463-53-8
• EC Number: 219-562-5
• FEMA: 3213
• SMILES: CCCCCC/C=C/C=O

Properties

• Boiling point: 88-90 °C (12 mmHg)
• Refractive index: 1.454-1.46

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315
• Safety Statements: P264-P280-P302+P352-P321-P332+P317-P362+P364

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Flammable liquids	Flam. Liq.	2	H225

Discovery and Applications

2-Nonenal is a volatile organic compound that belongs to the class of aliphatic aldehydes. It was first identified in the mid-20th century as part of research into the chemical composition of various natural and synthetic substances. This compound is known for its distinctive odor, which is often described as fatty, grassy, or even resembling the smell of old or greasy oils.

The discovery of 2-nonenal was largely driven by its presence in the aroma profiles of several natural sources, including certain fruits and vegetables. It was identified through chromatographic and spectrometric techniques that aimed to analyze and characterize the complex mixtures of volatile compounds responsible for specific scents. The identification of 2-nonenal added to the understanding of how various aldehydes contribute to the overall sensory properties of natural products.

In the fragrance industry, 2-nonenal is valued for its unique olfactory characteristics. Its fatty and waxy aroma makes it a useful ingredient in perfumery, where it can be used to create complex and nuanced scents. It is often incorporated into fragrances to add depth and richness, contributing to the overall sensory experience of perfumes and colognes. Additionally, 2-nonenal is used in flavorings to impart specific flavor notes that enhance the taste of various products.

Beyond its applications in fragrance and flavor industries, 2-nonenal is also studied for its potential role in other areas. For instance, it has been investigated for its presence in human body odors, where it can contribute to the characteristic smell of aging skin. This has implications for personal care products and dermatological research, where the compound's presence can be used to understand changes in skin chemistry over time.

The compound’s utility extends to research on lipid oxidation and related processes. 2-Nonenal is often used as a marker in studies investigating the stability and degradation of fats and oils. Its formation as a byproduct of lipid oxidation makes it a valuable compound for monitoring and analyzing oxidative processes in various food and cosmetic products.

While 2-nonenal is generally considered safe in the concentrations used in fragrances and flavorings, its handling requires adherence to standard safety practices to avoid exposure to high levels. Its diverse applications highlight its importance in both commercial and research contexts, underscoring its role in the fields of chemistry and sensory science.

References

1948. The Preparation of 2-Heptenal and 2-Nonenal. *Journal of the American Chemical Society*, 70(7).
DOI: 10.1021/ja01187a511

2024. Dynamic changes in quality and flavor compounds of pork tendons during puffing process. *npj Science of Food*, 8(1).
DOI: 10.1038/s41538-024-00325-3

2024. Quality characteristics of a red chili oil product processed via oil infusion: effects of pre-heated oil temperature. *Journal of Food Measurement and Characterization*, 18(7).
DOI: 10.1007/s11694-024-02676-7