Comparison of extraction and refinement techniques for volatile compound analysis in camellia oil

Zhe Cai; Qinbo Jiang; Ruihao Zhang; Yifang Ma; Kaini Chen; Shijie Zheng; Peng Li; Cheng Zeng; Hui Zhang

doi:10.1016/j.foodchem.2024.142501

Comparison of extraction and refinement techniques for volatile compound analysis in camellia oil

Food Chem. 2024 Dec 18:469:142501. doi: 10.1016/j.foodchem.2024.142501. Online ahead of print.

Authors

Zhe Cai¹, Qinbo Jiang¹, Ruihao Zhang², Yifang Ma¹, Kaini Chen¹, Shijie Zheng¹, Peng Li¹, Cheng Zeng³, Hui Zhang⁴

Affiliations

¹ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, PR China.
² College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314100, PR China.
³ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, PR China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314100, PR China. Electronic address: zengcheng0120@zju.edu.cn.
⁴ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, PR China. Electronic address: hubert0513@zju.edu.cn.

PMID: 39709918
DOI: 10.1016/j.foodchem.2024.142501

Abstract

The processing techniques of camellia oil, containing freshly squeezed (FSCO), refined (DFCO), cold-pressed (OFCO), and hot-pressed (RFCO), significantly influence flavor compounds and organoleptic properties. In this study, the preference for FSCO and RFCO was revealed by sensory evaluation due to the "fruity" and "roasted" flavors, respectively. Flavor differences among oils were accurately distinguished by the E-nose. A total of 77 and 116 odorants were identified by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and gas chromatography-mass spectrometry (GC-MS), respectively. The gas chromatography-olfactometry (GC-O) and detection frequency analysis identified 34 active-aroma compounds with DF ≥ 2. Aroma recombination and omission experiments further confirmed that (E)-2-nonenal and nonanal, derived from the degradation of unsaturated fatty acids, significantly contributed to "green" and "fruity" aromas. Notably, these concentrations positively correlated with sensory preference. This study provides valuable insights into the flavor identification of camellia oil and the improvement of processing techniques.

Keywords: Camellia oil; Detection frequency analysis; Flavor analysis; Oil processing technique.