Effect of dilute acid hydrolysis on the cooked viscosity of tarhana, a traditional Turkish cereal soup

Abstract

Tarhana, a traditional Turkish soup largely used in feeding infants due to its high nutritional value, was hydrolysed using HCL to obtain low viscosity at high dry matters. The effect of acid concentration (0.2–1.0 N), time (2–6h), and temperature (30–60°C) on the cooked viscosity of tarhana soup was investigated using response surface methodology. A second-order polynomial equation for predicting tarhana soup viscosity was developed. Acid concentration had the most pronounced effect on the viscosity, followed by temperature and time of hydrolysis. The interaction of time with temperature was also found significant. It is suggested that the regression equation can be used to find optimum hydrolysis conditions for the desired viscosity of tarhana soups.