摘要：In this research, some physical chemical and microbiological properties of 20 strained yoghurt samples taken form Ankara market were determined and their conformity to Food Regulation were studied. The extreme values of total solids of the samples range from 14.99% to 27.25%, having an average value of 19.41%. It is understood that to reach the total solids value that given in Food Regulation for strained yoghurt is rather difficult by using traditional process. According to the fat content while 15% and 25% of yoghurt samples were found in “full fat” and “half skimmed” classes respectively, the other 60% of samples were found in “skimmed” class. According to the protein contents of strained yoghurt (av. 12.01%) might be considered as a rich sources of protein. As the buffer capacity that depends on the protein level increased, the keeping quality of the product influenced positively. Average values of lactose, minerals, acetaldehyde and lactic acid for the samples were found as 4.18%, 0.673%, 8.98 ppm and 0.728 g/100 ml respectively. Titratable acidity values of 12 samples (60%) were not agreeable with the values of Food Regulation. PH values of samples ranged within 3.25 and 3.87, having and average value of 3.52. Average value of Tyrosine which reflects proteolysis was found as 0.165 mg/5 mil. None of the samples shown whey separation. Microbiological results indicated that the hygienic quality of yoghurts were unsatisfactory .
