# Compounds of Essential Oils from Different Parts of Cinnamomum cassia and the Perception Mechanism of Their Characteristic Flavors

## TL;DR

This study compares the flavor compounds in essential oils from cinnamon bark and leaves, explaining how they differ and how these differences affect their use in food.

## Contribution

The study identifies key volatile compounds and their roles in flavor perception in cinnamon bark and leaf essential oils.

## Key findings

- Cinnamaldehyde, α-caryophyllene, and borneol are key aroma compounds in bark essential oil.
- Nerolidol and α-caryophyllene significantly contribute to leaf essential oil flavor.
- Differences in aroma perception relate to compound concentrations and interactions with olfactory receptors.

## Abstract

This study investigated the differences in key volatile organic compounds (VOCs) and flavor characteristics between essential oils (CEOs) from cinnamon bark and leaf. The volatile compounds of essential oils extracted from Cinnamomum cassia (Xijiang) bark (CEOP) and leaf (CEOY) by hydrodistillation were identified using GC-MS. The results showed that the extraction rates of CEOP and CEOY were 1.56% ± 0.02 and 0.83% ± 0.01 (n = 3), respectively. CEOP and CEOY consisted of 45 and 50 compounds, respectively. Odor activity value (OAV) analysis indicated that cinnamaldehyde (OAV = 935), α-caryophyllene (OAV = 77), and borneol (OAV = 4) played key roles in shaping the aroma of CEOP. Meanwhile, cinnamaldehyde (OAV = 849), nerolidol (OAV = 107), and α-caryophyllene (OAV = 58) were the major contributors to the flavor of CEOY. Electronic nose (E-nose) analysis revealed that sensors W5S and W1W were important for detecting aromatic compounds. Sensory evaluation showed that CEOs differed significantly in spicy, floral, and grassy aromas. These differences may be related to the concentrations of compounds such as cinnamaldehyde, α-caryophyllene, and nerolidol, as well as their interactions with olfactory receptors such as OR2W1 and OR1D2. Cinnamaldehyde activates TRPA1 and TRPV1 to elicit the perception of spiciness. Thus, CEOP may be suitable for baked goods, and CEOY may be suitable for ice cream and beverages. In conclusion, this study provides a theoretical foundation for the precise application of CEOs as condiments in food.