Characterization of Volatile Compounds and Aroma Profiles of Malaysian Pomelo (Citrus grandis (L.) Osbeck) Blossom and Peel

The knowledge of the chemical compositions and sensory profiles of their peels and blossoms could lead to better understanding of two cultivars of Malaysian pomelo. This work was to determine the volatile compositions of Malaysian pomelo blossoms and peels through HS-SPME GC/MS analysis and principal component analysis (PCA) approach as well as to identify their key aroma profiles by sensory evaluation. Pink and white pomelo blossoms contained similar volatiles, which mainly consisted of limonene, cis-beta-ocimene, alpha-terpinene, linalool, methyl anthranilate, and indole. Their primary difference was in the concentration ratio between limonene and limdool. Major volatiles in pomelo peels were terpene hydrocarbons. Pink pomelo peel contained higher levels of aldehydes (e.g. octanal, decanal and citral), while some trace-level important compounds (e.g. beta-sinensal, alpha-sinensal and nootkatone) were found only in white pomelo peel. Through sensory evaluation, both intact pomelo blossoms had similar aroma profiles, which comprised the dominant note of floral, followed by animalic and citrus blossom. Additionally, pink pomelo peel extract was much more impactful than white pomelo peel extract, especially in grapefruit and green notes. Through HS-SPME GC/MS and PCA, the authors managed to discover the similarities and differences between two Malaysian pomelo cultivars. Further, the sensory data on intact pomelo blossoms and pomelo peel extracts provided more insight.