Effect of the protein addition on the structure of set style and stirred yoghurt with and without the use of transglutaminase

Abstract

Yoghurt production in Chile is increasing. Dairy industry exportations grown 45% in the past 2003–2004 period. From the total liquid milk production a 20% is used in the yoghurt process. It is important to mention that yoghurt in Chile is produced without protein addition and that the main yoghurt variety in the Chilean market is stirred yoghurt. Therefore, is interesting to increase the yoghurt quality and to investigate new applicable technologies. Membrane process in yoghurt production is a new technology (use of UF concentration to increase the dry matter) and, in the other hand, transglutaminase (TG) has been used mainly in the meat and soybean industry and not in the dairy one. Therefore the effect of the ultrafiltrated (UF) concentrate and skim milk powder on the structure of set style and stirred yoghurt were analyzed with and without the use of microbial TG. The effects of UF concentrate and the use of TG were evaluated. 2. Results and discussion