Characterization of virgin olive oils produced in Çanakkale region

In this research, samples of natural olive oils produced in the Çanakkale region olive oil factories in the January-February 2006, produced from the harvest of 2005-2006 production season were used. The quality parameters of some physical, chemical and sensorial properties were measured and compared with the Turkish Olive Oil Standard (TS 341), Codex Standard and published literature to draw practical conclusions. When the physical properties of the natural olive oils were analyzed, the refractive index of 1,4670-1,4680; viscosity of 60,4-66,1 cP; total volatiles of 0,09-0,25% values were measured. The instrumental color values of the samples were as follows: L values of 25,37-40,53; a* values of ? 9,60-16,14 and b* values of 19,97-46,11. Most of the measured values were within the limits of the `extra natural and natural olive oils? given as in the standards. When the measured chemical properties are examined, the free acidity value was 0,37-9,47 (as oleic acid%), peroxide value was 7,86-29,75 meqO2/kg, total phenolics content was 34,60-162,61 mg gallic acid/kg and antioxidant capacity was 0,25-1,66 mmol TE/kg. In this research, the sensorial properties of the natural olive oils were determined by the Quantitative Descriptive Analysis (QDA), and the panel were determined Çanakkale olive oils appearance by `yellowness?, `greenness? and `clarity? terms; aroma properties by `olive?, `grassy?, `rancid? and `musty/muddy? terms; flavor properties by `acid?, `astringent?, `bitter?, `soap? and `metallic? terms; and mouthfeeling properties by `throatcatching? and `thickness? terms. Comparison of the counties over the measured QDA data by appropciate statistical analyses were also completed. In addition, in order to determine the consumer preferences of the analyzed olive oil samples, each samples by 50 consumers were analyzed by utilizing Hedonic test. Accordingly, the preference scores of all samples were found above 30% value. Statistical analyses by multivariance analysis, correlation and canonical correlation analyses and stepwise regression analysis of the measured data have shown that the chemical and physical properties of Çanakkale region natural olive oils are in accordance with the standards and published literature. The terminology developed for sensorial characterization of the samples was similar to some in published studies and compared when appropciate. For the region olive oils, the sensrorial characterization was first time evaluated and presented to the science literature. Also, the measured physico-chemical and sensorial properties were tested by the Canonical Correlation Analysis (CCA) for the multiple correlations inherited within. In conclusion, the natural olive oils produced in the Çanakkale region are special among themselves, and there is no statistically significant differences among the 5 producing counties for most of the measured properties except the sensorial appearance. Accordingly, the oils of Eceabat was more green less yellow than other counties, while Bayramiç samples were less clear than all others. Meanwhile Ayvacık, Ezine and Gökçeada oils were the same and very yellow with small amount of greenness, and higher clarity. For the small number of samples, the peroxide value and K232 value were out of the standards. It was estimated that this is a result of unproper storage and conditions of storage must be improved. Mostly grassy and olive aromatic, a little bitter oils of Çanakkale are very low on the musty/muddy, rancid, metalic and soap characteristics. The oils defined as very yellow and clear with small amount of greenness in appearance. It is expected that the results of this study will help to both resolve region olive oil production problems and to enhance their qualities, as well as to contribute to their exploitation. Key word; Çanakkale, Natural olive oil, Quality, Sensory, Canonical correlation analysis.