Physico-chemical and Sensory Properties of Tarhana Prepared from Different Cereals and Dairy Ingredients
Mohamed F. Y. Hassan
Department of Dairy Science, Faculty of Agriculture, Sohag University, Sohag, Egypt. and Department of Food Science and Human Nutrition, Faculty of Agriculture and Veterinary Medicine, Qassim University, Buraidah, Saudi Arabia.
Mohamed G. E. Gadallah *
Department of Food Science and Human Nutrition, Faculty of Agriculture and Veterinary Medicine, Qassim University, Buraidah, Saudi Arabia. and Department of Food Science, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.
*Author to whom correspondence should be addressed.
Abstract
Tarhana is a traditional fermented food made from cereals and yoghurt mixture and popular in some European and African countries. In this study, the effects of wheat, oat or barley flour with cow or goat yoghurt on the physico-chemical and sensory properties of Tarhana were investigated. A gradually increased in acidity of all prepared Tarhana dough samples was found during fermentation time. The acidity of Tarhana powder ranged between 0.78% for Tarhana made from oat flour and goat yoghurt to 2.12% when using barley flour with goat yoghurt. In addition, incorporated barley flour and goat yoghurt in Tarhana resulted in significant increase in total phenolic compounds and antioxidant activity being (27.23 mg GAE/g) and 47.45%, respectively. It could be stated that all Tarhana samples are good source of minerals especially K, Na and Mg. A significant increase in lightness (L) being 71.75 and total intensity of color being 72.46 was exhibited by Tarhana prepared from oat flour and cow yoghurt compared to all other treatments. All of Tarhana treatments were significant increase in redness (a), yellowness (b) and chroma except Tarhana samples prepared from barley flour. It could be seen that all Tarhana soups behaved as non-Newtonian fluid (pseudoplastic) whereas, the viscosity was gradually decreased with increasing the rotational speed (rpm). All of the Tarhana soups were acceptable in sensory properties except when using barley flour which need to improve their color. Tarhana soup with wheat flour and cow or goat yoghurt samples had valuable high scores in color (8.7 and 8.0), taste (8.7 and 8.7) and overall acceptability (8.9 and 8.7) and being more preferable by the panelists. It can be concluded that Tarhana supplemented with oat or barley flour can be claimed to be a good sources of minerals, phenolics as well as antioxidant activity and considered as a functional food.
Keywords: Tarhana, oat, barley, physico-chemical, antioxidant activity, sensory parameters