In this study, some physical and chemical properties of pekmez samples produced using the traditional method with fourteen different grape cultivars were investigated. The water-soluble dry matter, pH, titratable acidity and hydroxymethylfurfural (HMF) content of the samples were determined to be 66.19-80.57%, 3.59-5.23, 0.27-1.81 g 100 g-1 and 5.93-762.22 mg kg-1, respectively. The mean fructose and glucose contents of the pekmez samples were determined to be 28.42 g 100 g-1 and 31.67 g 100 g-1, respectively. The densities and electrical conductivities varied between 1.33-1.43 g cm-3 and 1.96-4.51 mS cm-1, respectively. The content of the macro element K identified in the pekmez samples (4449.86 mg kg-1) was greater than that of Ca (1275.52 mg kg-1), P (369.96 mg kg-1), Mg (344.79 mg kg-1) and Na (119.56 mg kg-1). The pekmez samples have antioxidant activities, ranging between 38.20 to 64.45 μmol TE g-1. Six phenolic compounds, caffeic acid, ellagic acid, ferulic acid, gallic acid, p-coumaric acid and rutin hydrate, were identified in the pekmez samples, and significant differences were observed between samples (P<0.01).
Bu çalışmada on dört farklı üzüm çeşidinden geleneksel olarak üretilen pekmez örneklerinin bazı fiziksel ve kimyasal özellikleri incelenmiştir. Örneklerin suda çözünür kuru madde miktarı, pH, titrasyon asitliği ve hidroksimetilfurfural (HMF) içerikleri sırasıyla % 66.19-80.57, 3.59-5.23, 0.27-1.81 g 100 g-1 ve 5.93-762.22 mg kg-1 olarak belirlenmiştir. Pekmez örneklerinin ortalama fruktoz ve glikoz içerikleri sırasıyla 28.42 g 100 g-1 ve 31.67 g 100 g-1 olarak saptanmıştır.1. IntroductionPekmez (molasses), which has been produced for a long time in Turkey, is one of the popular and traditional Turkish foods (Tosun & Üstün 2003). Pekmez is a concentrated and extended shelf-life form of several fruit juices, and it is formed by boiling without the addition of sugar or other food additives (Yoğurtçu & Kamışlı 2006). Pekmez is produced primarily from grapes by concentrating juices with a soluble dry matter content of up to 7080% (Alpaslan & Hayta 2002; Batu et al 2007). In Turkey, approximately 4185.126 tons of grapes are produced per year (TUIK 2012), and approximately 30% of the grapes produced in Turkey are used for pekmez, wort and sausage with pekmez production in a year. Furthermore, some fresh or dried fruits that contain high amounts of sugar, such as fig, mulberry, carob, juniper, sugar beet, sugar cane, melon, watermelon, apple and apricot, can also be used to produce pekmez (Karababa & Isikli 2005; Akbulut et al 2008). Fresh fruits are directly squeezed, whereas dried fruits are subjected to extraction in an aqueous medium and then pressed and derived extract called as must is homogenized (Aliyazıcıoğlu et al 2009).Pekmez samples are produced in all regions of Turkey and are named after the geographic locations in which they are produced, such as Zile Pekmez in Zile, Ağda in Gaziantep, Çalma in Kırşehir, Bulama in Balıkesir and Masara in Kahramanmaraş (Tosun & Üstün 2003). However, the varieties of grapes and processing techniques used in pekmez production can be different in these regions. Pekmez is produced using traditional and vacuum evaporation methods in