Some Chemical and Physical Properties, Fatty Acid Composition and Bioactive Compounds of Wheat Germ Oils Extracted From Different Wheat Cultivars

Bu çalışmada, Türkiye'de yaygın olarak yetiştirilmekte olan iki ekmeklik (Triticum aestivum L.) ve bir makarnalık (Triticum durum L.) buğday çeşitlerinden elde edilen rüşeym yağlarının; yağ asidi kompozisyonu, antioksidan aktivite,1. IntroductionCereals and cereal-based foods are the major nutritional sources for human in Turkey as well as in the world. Wheat is placed on the top among the cereal plants consumed (Çifci & Doğan 2013). Triticum aestivum (bread type), Triticum durum (durum) and Triticum compactum (biscuit, Topbaş wheat) are major wheats grown in Turkey and all over the world (Hoseney 1994; Bushuk 1998). Wheats having horny endosperm are generally used for production of leavened foods such as bread, pastry and bagel while the ones having floury endosperm are utilized for bakery products such as biscuit, cracker, waffle and cake, which are produced with chemical leavening agents. Durum wheat is used for production of semolina for pasta and spaghetti, and granular products including bulgur and kuskus. Since production level of Topbaş wheat is very low, bread type wheat which has low protein level and quality is preferred for biscuit production (Hoseney 1994; Elgün & Ertugay 1995; Bushuk 1998; Morris 2004). Indeed, differences in hardness among Triticum aestivum L. or between T. aestivum L. and T. turgidum L. ssp. durum wheat cultivars determine not only their milling properties, but also the properties of flour or semolina endosperm particles, their preferential use in cereal-based applications, and the quality of the latter (Pauly et al 2013).Wheat germ is one of the by-products of wheat milling. Germ constitutes 2-3% of the wheat grain and contains approximately 8-14% oil in its composition. Several health benefits of wheat germs were attributed to germ oil, such as the plasma and hepatic cholesterol lowering effect and toplam fenolik madde ve ?-tokoferol miktarları araştırılmıştır. Ruşeym yağı örneklerinde toplam 14 farklı yağ asidi tespit edilmiş olup, bütün numunelerde hakim yağ asitleri; linoleik asit (% 53.88-57.55), oleik asit (% 16.56-20.38) ve palmitik asit (% 16.66-17.70) olarak saptanmıştır. Ruşeym yağı örneklerinin antioksidan aktivitelerinin 0.94 µmol g-1ile 1.01 µmol g-1, toplam fenolik madde miktarlarının 67.79 mg GAE 100 g-1 ile 126.51 mg GAE 100 g-1 ve ?-tokoferol içeriklerinin 1343 mg kg-1 ile 2176 mg kg-1 arasında değiştiği tespit edilmiştir. Antioksidan aktivite ve toplam fenolik madde miktarı bakımından en düşük oranın ekmeklik çeşitte, en yüksek antioksidan aktivitenin ise diğer ekmeklik çeşitte bulunduğu ve en yüksek toplam fenolik maddenin makarnalık çeşitte bulunduğu görülmüştür.

Farklı Buğday Çeşitlerinden Ekstrakte Edilen Rüşeym Yağlarının Kimi Kimyasal ve Fiziksel Özellikleri, Yağ Asidi Kompozisyonu ve Biyoaktif Bileşikleri

Fatty acid composition, antioxidant activity, total phenolics and ?-tocopherol contents of wheat germ oils obtained from two bread wheats (Triticum aestivum L.) and one durum wheat (Triticum durum L.) species commonly cultivated in Turkey were investigated in this study. Fourteen different fatty acids were determined in wheat germ oil samples in which linoleic acid (53.88-57.55%), oleic acid (16.56-20.38%) and palmitic acid (16.66-17.70%) were found as predominant fatty acid types. Among the major fatty acids, linoleic acid was the primary fatty acid in bread wheat germ oils whereas oleic and palmitic acids were the predominant fatty acids in durum wheat samples. The antioxidant activity of the wheat germ oil samples ranged between 0.94-1.01 µmol g-1 whereas the total phenolic and the ?-tocopherol between 67.79-126.51 mg GAE 100 g-1 and 1343 to 2176 mg kg-1, respectively. The lowest antioxidant activity and total phenolic content were detected in bread wheat germ oil while the other bread wheat and the durum wheat exhibited the highest antioxidant activity and total phenolic content, respectively.

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