Gas Chromatography-Mass Spectrometry Analysis as a Tool to Reveal Differences Between the Volatile Compound Profile of Royal Jelly Produced from Tea and Pagoda Trees

Abstract

Royal jelly produced by nurse bees from tea tree (tea royal jelly) is a special bee product in China and it is popular with consumers owing to its multiple healthcare functions. However, the volatile compound profile of tea royal jelly has not been investigated. To obtain a comprehensive understanding of volatile compound profile of tea royal jelly, a method based on headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) and chemometric analysis was applied. Moreover, two royal jelly samples produced from pagoda tree were also investigated to reveal the difference in volatile compounds between royal jelly produced from tea tree and other plants. A total of 66 volatile compounds were identified in tea royal jelly, including 16 alkanes, 14 aldehydes, 9 alcohols, 9 ketones, 8 esters and lactones, 5 phenols, 2 organic acids, and 3 other compounds, and most of them were discovered in royal jelly for the first time. Notably, α-ionone, an important aroma compound in tea, was first identified in tea royal jelly. Moreover, the result of chemometric analysis indicates a significant difference on volatile compound profile between royal jelly produced from tea and pagoda trees. To sum up, 35 differential compounds were identified and they could well distinguish royal jelly samples. Our data offers the first characterization of volatile compound profile of tea royal jelly and significantly expands the knowledge of volatile compounds in royal jelly. It is potentially useful as a new approach to distinguish royal jelly produced from different botanical origins.