Volatile profiles of Murcott and Ponkan mandarins obtained by stir bar sorptive extraction technique and their contributions to the fruit aroma.

ABSTRACT

Citrus species have undergone immense diversification ever since their ancestral origin. Ponkan and Murcott are two mandarin varieties widely consumed in Brazil and their aroma producing active compounds have not yet been extensively investigated. The present study analyzed the volatile constituents of the Ponkan and Murcott varieties employing the stir bar sorptive extraction (SBSE) technique and gas chromatography-mass spectrometry (GC-MS) analysis for the first time. Extraction was performed using the two phases of Twister bar, polydimethyl siloxane (PDMS), and ethylene glycol (EG) silicone in immersion and headspace modes. Among the detected 62 compounds comprising alcohols, aldehydes, esters, terpenes, and others identified, 55 and 37 compounds in the Ponkan and Murcott variety were determined, respectively, from both immersion and headspace modes using the two phases of Twister bar. From the odor active values, the Ponkan was characterized with the domination of compounds such as hexanal, decanal, nonanal, (E)-2-hexanal, ethyl hexanoate, d-limonene, linalool, and geraniol. Similarly, the Murcott variety was characterized with predominant compounds, namely, nonanal, octanal, hexanal, (E)-2-hexanal, ethyl hexanoate, d-limonene, and linalool. The profile of volatile compounds was found to be unique in both the varieties studied, and SBSE technique with GC-MS analysis favored the characterization of their respective profile due to the high amount of phase in the Twister bars, when compared to similar techniques, like solid phase microextraction. The PDMS Twister bar showed better capacity of adsorption of volatile compounds, since it is a relatively low-polarity polymer, which discriminates less analytes with different structures and polarities sampled from complex matrices, such as fruits juice.