FARKLI ISITMA TEKNİKLERİNİN FINDIK VE KANOLA YAĞININ STEROL BİLEŞİMİNE ETKİSİ

Öz

Çalışmanın amacı farklı ısıtma tekniklerinin fındık ve kanola yağlarının sterol bileşimine etkisini belirlemektir. Bu amaçla, 50 ml rafine fındık ve rafine kanola yağı mikrodalga fırında 650 W güçte 1, 3, 5 ve 10 dk bekletilmiş; ısıtma sonunda yağ örneklerinin sıcaklıkları ölçülerek konveksiyonel ve hibrid fırında da aynı sıcaklığa (69.5, 129.4, 173.5 ve 238.0 °C) ulaşmayı sağlayan ısıtma işlemleri gerçekleştirilmiştir. Elde edilen yağ örnekleri sterol miktar ve kompozisyonu açısından değerlendirilmiştir. Bulgular hibrit fırının ısıtma hızının yüksek sıcaklıklarda diğer fırınlara kıyasla daha düşük olduğunu göstermektedir. Fındık yağının temel sterolleri β-sitosterol, kampesterol ve sitostanol olup ve toplam sterol içeriği 683.69-1544.09 mg/kg arasında değişmiştir. Tüm ısıtma yöntemlerinde sıcaklık artışı ile fındık yağının sterol içeriğinde genel olarak bir azalma meydana gelmiştir. Kanola yağı, β-sitosterol ve kampesterol yanında yağa özgü olarak yüksek oranlarda brassikasterol içermektedir. Kanola yağı örneklerinin toplam sterol içeriği 6088.28-9532.72 mg/kg arasında değişmiş ve ısıtma işlemleri yağda sterol kaybına yol açmamıştır.

Anahtar Kelimeler

• Fındık yağı,konveksiyon,mikrodalga,kanola yağı,sterol

EFFECT OF VARIOUS HEATING TECHNIQUES ON STEROL COMPOSITION OF HAZELNUT AND CANOLA OILS

Öz

The aim of the work was to determine effect of various heating techniques on sterol composition of hazelnut and canola oil. For this purpose; 50 ml of refined hazelnut and canola oil samples were kept in microwave oven at 650 W power for 1, 3, 5 and 10 minutes; the temperature of the oil samples were calculated at the end of heating; and the heating process were performed at convectional and hybrid ovens until the attained temperatures (69.5, 129.4, 173.5 ve 238.0 °C) were reached. The obtained oil samples were evaluated for their sterol content and composition. Findings revealed that the heating speed of hybrid oven was lower at higher temperatures when compared to other ovens. The main sterols of hazelnut oil were β-sitosterol, campesterol and sitostanol and the total sterol content varied between 683.69-1544.09 mg/kg. The sterol content of hazelnut oil generally decreased by the increase in temperature for all types of heating methods. Canola oil, contains brassicasterol in high ratios unique to the oil, besides, β-sitosterol and campesterol. Total sterol content of canola oil varied between 6088.28-9532.72 mg/kg and heating procedure didn’t cause a sterol loss in the oil.

Anahtar Kelimeler

• Hazelnut oil,convection,microwave,canola oil,sterol

Kaynakça

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