Characterization of volatile compounds in selected citrus fruits from Asia - Part II: Peel oil

The volatile compounds of the hand-pressed peel oil from the selected citrus fruits from Asia, namely Indonesian Pontianak oranges (Citrus nobilis Lour. var. microcarpa Hassk.), Indian Mosambi (Citrus sinensis Osbeck) and Philippine Dalandans (Citrus reticulata Blanco), were characterized by GC-FID and GC/MS. A total of 32 compounds were found in Pontianak orange, 29 in Mosambi and 37 compounds in Dalandan peel oils. Limonene dominated the composition of each of the oils and most of the compounds were present in the concentrations less than 0.1%. The absence of some important contributor compounds to mandarin family in Pontianak orange show that it is a mandarin that has unique characteristic flavor. The characteristic compound of sweet orange oil, delta-3-carene, was found in Mosambi peel oil. The presence of gamma-terpinene in Dalandan was exceptionally high (4.3%) compared with other cultivars. Isopiperitenone was the tentatively-identified volatile compound not frequently reported in other citrus fruits found in Dalandan peel oil. It could be the important contributor to the characteristic aroma of Dalandan despite its trace amount.