MEMECİK VE ERKENCE ZEYTİN ÇEŞİTLERİNDE OLGUNLUK DERECESİNİN NATÜREL ZEYTİNYAĞININ TOPLAM POLİFENOL MİKTARI VE ACILIK İNDEKSİ ÜZERİNDEKİ ETKİSİ

Öz

Natürel zeytinyağının karakteristik duyusal özellikleri arasında yer alan acılık, zeytinyağının yapısındakifenolik bileşiklerden kaynaklanmaktadır. Zeytinyağının önemli bir bileşeni olan fenolik bileşiklerin nitelve nicel özelliklerini; iklimsel, agronomik ve teknolojik faktörler belirlemektedir. Bu çalışmada; farklıolgunluk düzeylerinde hasat edilen Memecik ve Erkence çeşidi zeytinlerden elde edilen yağlarının toplampolifenol içeriği ile acılık indeksi K225değerindeki değişim incelenmiştir. Her iki zeytin çeşidinde deolgunlaşma ilerledikçe, toplam polifenol miktarının logaritmik olarak azaldığı ve bu değişimin istatistikselolarak önemli olduğu (P<0.05) belirlenmiştir. Memecik ve Erkence zeytin çeşitlerinden elde edilen yağlarıntoplam polifenol miktarı ile acılık indeksi K225arasındaki ilişkinin istatistiksel olarak önemli olduğu(P<0.01), bu ilişkinin matematiksel olarak logaritmik bir denklemle ifade edilebileceği saptanmıştır

Anahtar Kelimeler

• Zeytin, zeytinyağı, olgunlaşma indeksi, acılık indeksi, polifenol

INFLUENCE OF THE FRUIT'S RIPENESS ON TOTAL POLYPHENOL CONTENT AND BITTERNESS INDEX OF VIRGIN OLIVE OIL FOR MEMECIK AND ERKENCE OLIVE VARIETIES

Öz

Phenolic compounds are responsible from bitterness which is one of the desired sensory characteristicsof natural olive oils. Quantitative and qualitative properties of phenolic compounds in natural olive oilsdepend on climatic and agronomic factors as well as the olive oil processing technology. In this study;changes in total polyphenol content of olive oil extracted from Memecik and Erkence varieties at differentmaturation levels are investigated. Moreover; relation of total polyphenol content of olive oil withbitterness index K225is also examined. Total polyphenol content decreased in logarithmic manner asmaturation proceeds for both varieties. This dependence is found to be statistically significant (P<0.05).Relationship between total polyphenol content and bitterness index K225showed a logarithmic dependencewhich is also confirmed to be statistically significant (P>0.01) for Memecik and Erkence varieties

Anahtar Kelimeler

• Olive, olive oil, maturity index, bitterness index, polyphenol

Kaynakça

1. Garcia-Mesa JA, Mateos R. 2007. Direct automatic determination of bitterness and total phenolic compounds in virgin olive oil using a pH-based flow-injection analysis system. J Agric Food Chem, 55, 3863-3868.
2. Garcia-Mesa JA, Pereira-Caro G, Fernandez- Hernandez A, Civantos CGO, Mateos R. 2008. Influence of lipid matrix in the bitterness perception of virgin olive oil. Food Quality and Preference, 19, 421-430.
3. Franco MN, Sanchez J, De Miguel,C, Martinez M, Martin-Vertedor D. 2015. Influence of the fruit's ripeness on virgin olive oil quality. Journal of Oleo Science, 64, (3), 263-273.
4. Del Carlo M, Sacchetti G, Di Mattia C, Compagnone D, Mastrocola D, Liberatore L, Cichelli A. 2004. Contribution of the phenolic fraction to the antioxidant activity and oxidative stability of olive oil. J Agric Food Chem, 52 (13), 4072-4079.
5. Vitaglione P, Savarese M, Paduano A, Scalfi L, Fogliano V, Sacchi R. 2015. Healthy virgin olive oil: A matter of bitterness. Food Science and Nutrition, 55, 1808-1818.
6. Frankel E, Bakhouche A, Lozano-Sanchez J, Segura-Carretero A, Fernandez-Gutierrez A. 2013. Literature review on enriched in bioactive compounds: Potential use of by products as alternative sources of polyphenols. J Agric Food Chem, 61, 5179-5188.
7. Aguilera MP, Jimenez A, Sanchez-Villasclaras S, Uceda M, Beltran G. 2015. Modulation of bitterness and pungency in virgin olive oil from unripe "Picual" fruits. Eur J Lipid Sci Technol., 117, 1463-1472.
8. Beltran G, Aguilera MP, Del Rio C, Sanchez S, Martinez L. 2005. Influence of fruit ripening process on the natural antioxidant content of Hojiblanca virgin olive oils. Food Chem, 89, 207-215. 9. Johanneke LH, Busch HC, Hrncirik K, Blukin E, Boucon C, Mascini M. 2006. Biosensor measurement of polar phenolics for the assessment of the bitterness and pungency of virgin olive oil. J Agric Food Chem, 54, 4371-4377.

9. Artajo LS, Pomero MP, Morello JR, Motilva MJ. 2006. Enrichment of refined olive oil with phenolic compounds: Evaluation of their antioxidant activity and their effect on the bitter index. J Agric Food Chem, 54, 6079-6088.
10. Youssef NB, Zarrouk W, Carrasco-Pancorbo A, Ouni Y, Segura-Carretero A, Fernandez-Gutierrez A, Daoud D, Zarrouk M. 2010. Effect of olive ripeness on chemical properties and phenolic composition of chetoui virgin olive oil. J of Sci Food Agric, 90,199-204.
11. Dierkes G, Krieger S, Dück R, Bongartz A, Schmitz OJ, Hayen H. 2012. High-performance liquid chromatography-mass spectrometry profiling of phenolic compounds for evaluation of olive oil bitterness and pungency. J Agric Food Chem, 60, 7597-7606.
12. Apetrei C. 2012. Novel method based on polypyrrole-modified sensors and emulsions for the evaluation of bitterness in extra virgin olive oils. Food Res Int, 48, 673-680.
13. Favati F, Condelli N, Galgano F, Caruso MC. 2013. Extra virgin olive oil bitterness evaluation by sensory and chemical analyses. Food Chem, 139, 949-954.
14. Inarejos-Garcia AM, Androulaki A, Salvador MD. 2009. Discussion on the objective evaluation of virgin olive oil bitterness. Food Res Int, 42, 279-284.
15. Rosales FG, Perdiguero S, Gutierrez R, Olias JM. 1992. Evaluation of the bitter taste in virgin olive oil. J Am Oil Chem Soc, 69, 4, 394-395.
16. Uceda M, Frias L. 1975. Harvest dates, evaluation of the fruit oil content, oil composition and oil quality. Proc Segundo Seminario Oleicola Internacional, Cordoba, 125-130.
17. Gutfinger T. 1981. Polyphenols in olive oil. J Am Oil Chem Soc, 58, 966-968.