The Chemometric Classification of Ayvalik and Memecik Virgin Olive Oils Exposed to Daylight and Dark Based on Their Spectroscopic Data (Turkish with English Abstract)

Abstract

In this study, oil samples of Ayvalik and Memecik, domestic olive cultivars of Aegean region providing aproximately 65 % of virgin olive oil production of Turkey, were analysed and classified by using common spectroscopic (FTNIR, FTIR-ATR, Excitation-Emission [EX-EM] Fluorescence Spectroscopy and Synchronous [SYN] Fluorescence Spectroscopy) methods. The analysed oil samples consisted of totally 9 samples – except 1 mixed organic oil sample – taken from North Aegean [ Ayvalık olive cultivar] (n=4) and South Aegean [Memecik olive cultivar] (n=4) subzones. The samples were stored in PET glass at room temperature and they were divide into two groups including exposed to diffused day ligth and covered with aluminium folios [dark]. The classification of Ayvalık ve Memecik olive oil samples were carried out by the most used chemometric (Principal Component Analysis, PCA and Hierarchical Cluster Analysis, HCA) techniques. Ayvalık and Memecik oil samples were classified noticeable according to cultivars, origin district or processing applications (exposed to ligth or dark and store conditions) based on the results of spectroscopic methods. In additon, the spectroscopic methods could be exhibited promising effects for the correct classification – also, information on possible store conditions and adulterations – of virgin olive oil was seen.

Keywords

• Ayvalık, Memecik, virgin olive oils, FT-NIR, FTIR-ATR, EX-EM and SYN Fluorescence spectroscopy, chemometry, classification.  

Karanlık ve Aydınlıkta Depolanmış Ayvalık ve Memecik Çeşidi Natürel Zeytinyağlarının Spektroskopik Verilere Göre Kemometrik Sınıflandırılması

Abstract

Bu çalışmada, Türkiye’nin zeytinyağı üretiminin % 65’ini Oluşturan Ege bölgesinin hakim zeytin çeşidi olan Ayvalık ve Memecik yağ örneklerinin en yaygın spektroskopik yöntemler ile (FTNIR, FTIR-ATR, Excitation-Emission [EX-EM] ve Senkronize [SYN] Floresans Spektroskopisi) analiz edilerek sınıflandırılması gerçekleştirilmiştir. Analiz edilen yağ örnekleri organik ve karışık çeşitlerden üretilen bir örnek dışında Kuzey Ege (Ayvalık çeşidi) (n=4) ve Güney Ege (Memecik çeşidi) (n=4) alt bölgelerinden alınmış toplam 9 adetten Oluşmaktadır. Oda sıcaklığında PET şişeler içinde muhafaza edilen yağ örnekleri gün ışığına maruz bırakılan ve aluminyum folyo ile kaplanmış (karanlık) olarak iki gruba ayrılmıştır. Ayvalık ve Memecik çeşidi natürel zeytinyağlarının sınıflandırılması en yaygın kullanılan kemometrik yöntemler ile (Temel Bileşen Analizi, PCA ve Aşamalı Kümeleme Analizi, HCA) gerçekleştirilmiştir. Ayvalık ve Memecik çeşitleri spektroskopik yöntemlerin sonuçları temelinde çeşit, orijin bölgesi ve işlem uygulamalarına (ışığa maruz kalma veya karanlıkta tutma gibi) göre dikkate değer bir şekilde sınıflanmışlardır. Ayrıca, spektroskopik yöntemlerin natürel zeytinyağların sınıflandırılmasında ve muhtemel depolama koşulları ve tağşiş konusunda ümitvar etkiler sergileyebileceği görülmüştür.

Keywords

• Ayvalık, Memecik, natürel zeytinyağı, FT-NIR, FTIR-ATR, EX-EM, SYN Floresans spektroskopisi, kemometri, sınıflandırma.  

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