SPME-GC ile Türk goji meyvelerinin aroma profillerinin incelenmesi

Goji berry (GB) is a powerful antioxidant used in Chinese medicine to reduce cholesterol, lower blood pressure, and clean blood. GB is an authentic fruit with orange, red color and tangy flavor. It is aimed to determine the volatile profile, phenolic compounds, elemental compositions and antioxidant activity of the dried GB samples of Turkish origin which has been increasingly used all over the world in recent years. The volatile organic compounds found in GB samples were extracted using headspace-solid phase microextraction and determined by gas chromatography-mass spectrometer using commercial SPME fiber. The phenolic compounds found in GB samples were analyzed by HPLC. The elemental composition of the GB sample was determined with ICP-OES following acid digestion. Antioxidant activity of GB sample was determined by DPPH based method. The volatile organics of GB sample were also determined by hydrodistillation method. The extraction efficiencies of polyacrylate and divinylbenzene/carboxen/ polydimethylsiloxane SPME fibers were found higher than the hydrodistillation method. In SPME method, the extraction temperature and extraction time were optimized as 60 oC and 60 min, respectively. Some identified compounds are safranal, nonanal, geranyl acetone, benzophenone, fatty acids like ethyl palmitate, methyl oleate, methyl linoleate, etc. Na, K, Mg, Ca and P as macro elements, Fe, Cu, Mn, Zn, Se, V as minor elements and Cd, Hg, and Pb as trace elements were determined in the GB samples. These elements and the phenolic compounds showed similar contents with the previous works. The black GB sample has the highest antioxidant activity.