PEKMEZ-TAHİN KARIŞIMLARININ TRİBOLOJİSİ

Year 2018, , 582 - 590, 15.06.2018

Filiz Altay , İpek Altay

https://doi.org/10.15237/gida.GD18026

Cited By: 1

Abstract

Son zamanlarda, gıdanın ağızda
çiğnenirkenki yapısını açıklayabilecek “triboloji” ya da “ince film reolojisi”
adı verilen bir yaklaşım önemli hale gelmiştir. Bu çalışmada, ağırlıkça 30:70,
40:60, 50:50 oranlarındaki pekmez-tahin karışımlarının tribolojik deneyleri
modifiye edilmiş bir sensörle tribometre kullanılarak yürütülmüştür. Bu
ölçümlerden sürükleme hızına karşı sürtünme katsayılarının çizildiği Stribeck eğrisi
adı verilen grafikleri elde edilmiştir. Bu grafiklerde her bir örnek için
hidrodinamik (sürtünme viskozite yüzünden hız ile doğrusal olarak artar)  ve sınır bölgeleri (nispeten sabit sürtünme
görülür) tespit edilmiştir. Ağırlıkça 50:50 pekmez-tahin içeren örnek diğer
örneklere göre daha düşük bir hızda, temas yüzeyleri arasında ince bir yağlama
tabakasının geliştiğini gösteren hidrodinamik bölgeye girmiştir. Diğer yandan
sürtünme, örneklerin yağ içeriği arttıkça azalmıştır. Bu durum bütün örnekler
için düşük hız bölgesinde daha belirgindir. Bileşimi birbirine yakın
dolayısıyla viskoziteleri birbirine yakın bu örneklerin tribolojik ölçümleri,
yapısal farklılıkları daha iyi ortaya koymuştur. Gıdaların tribolojik
özellikleri, bunların reolojik ve duyusal özelliklerle ilişkisinin
araştırılması için çalışmalar yapılması gerekmektedir.

Keywords

triboloji, sürtünme, yağlama, tahin, pekmez

TRIBOLOGY OF PEKMEZ (GRAPE MOLASSES)-TAHİN (SESAME PASTE) MIXTURES

Abstract

A new field of texture analysis
called “tribology” or “thin film rheology” that might explain the food texture
throughout oral processing has become important. In this study, tribological
experiments for samples containing pekmez and tahin at 30:70, 40:60 and 50:50
(w/w) were conducted by using a modified pin-on-disk tribometer. In the
Stribeck curves hydrodynamic and boundary regions were determined. For the
mixture containing pekmez:tahin at 50:50, hydrodynamic region started at a
lower speed compared to other samples, which indicated a developing a thin
lubrication film between contact surfaces. The friction decreased with the oil
content of the sample. This was more profound in the lower speed region for all
samples. Tribological data provided more distinct evaluation compared to the
viscosity data which were close to each other due to similar composition of
samples. Further research are needed on tribological properties of foods, their
relation to rheology and sensory analysis.

Keywords

tribology, friction, lubrication, sesame paste, grape molasses

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