Effects of heat treatment and starter culture on the properties of traditional Urfa cheeses (a white-brined Turkish cheese) produced from bovine milk A. Ferit Atasoy a, * , Atilla Yetis ßmeyen b , Hu ¨seyin Tu ¨ rkog ˘lu c , Barbaros O ¨ zer c a Sanlıurfa Vocational High School, Department of Food Technology, Harran University, 63010 Sanlıurfa, Turkey b Faculty of Agriculture, Department of Dairy Technology, Ankara University, Ankara, Turkey c Faculty of Agriculture, Department of Food Engineering, Harran University, Sanlıurfa, Turkey Received 5 December 2005; received in revised form 4 April 2007; accepted 10 April 2007 Abstract The objective of the present research was to determine the effects of heat treatment and starter culture on some properties of Urfa cheese produced from bovine milk. Proteolysis developed more rapidly in the cheese made with mesophilic starter culture. Whereas the cheese inoculated with thermophilic starter culture received higher sensory scores. High heat treatment (at 72 °C for 5 min) affected the sensory and chemical properties of Urfa cheese adversely. Therefore, incorporation of low heat treatment (at 65 °C for 20 min) is recommended for the production of Urfa cheese, with addition of a culture of Lactococcus lactis subsp. lactis + Lactococcus lactis subsp. cremoris. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Urfa cheese; Heat treatment; Starter culture 1. Introduction Urfa cheese is a traditional semi-hard brined Turkish cheese type produced mainly in the southeast Anatolia region of Turkey from raw ovine milk or appropriate mix- tures of ovine and caprine milk, without any starter cul- ture. Since lactation period of ovine and caprine milk in Turkey is very short (approximately 6–7 months), it is not always possible to extend Urfa cheese production over the all year without the use of bovine milk. Recently, the industrial production of Urfa cheese has been made from bovine milk, and therefore, today this cheese variety has gained nationwide popularity. The final sensory quality of cheese is affected by the treatment of milk including heat treatment. Heat treatment to cheese milk is important in order to maintain uniform quality, promote safety and achieve better production con- trol. The safety aspect is the driving force for making cheese from pasteurized milk (Pandey, Ramaswamy, & St-Gelais, 2003). Despite the safety concern, there is still a large demand for cheeses made from raw milk because they possess strong and unique flavours, and therefore, raw milk cheeses are popularly sold in many parts of the world including Turkey. Raw milk cheese has often been associated with outbreaks of diseases. Especially, cheese- borne salmonellosis, listeriosis and brucellosis are very common in southeast of Turkey where Urfa cheese produc- tion is prevailing (O ¨ zer, Uraz, Yılmaz, & Atasoy, 2004). Therefore, raw milk cheeses are suggested to be stored under appropriate conditions at least 90 days before con- sumption (Kurt, 1996). In order to minimize the risk of microbial contamination, raw milk was replaced with pas- teurized milk in the production of Urfa cheese, without impairing the overall quality of the final product. 0956-7135/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodcont.2007.04.004 * Corresponding author. Tel.: +90 414 247 03 91/279; fax: +90 414 247 03 92. E-mail address: afatasoy@hotmail.com (A.F. Atasoy). www.elsevier.com/locate/foodcont Available online at www.sciencedirect.com Food Control 19 (2008) 278–285