August 12/Food & Farm Week -- According to a study from Sanliurfa, Turkey, "Reduced-fat stirred yogurts were prepared by using ropy and nonropy exopolysaccharide (EPS)-producing strains or nonexopolysaccharide-producing strains. Yogurts were evaluated for pH, titrable acidity, acetaldehyde, whey separation, viscosity, EPS concentration, sensory and microbiological analyses."

"Determinations of these parameters were made at 1, 7, 14 and 21 days of storage. Reduced-fat yogurts made with EPS+ strains exhibited lower syneresis and acetaldehyde contents, but higher viscosity than those made with the EPS strain," wrote M.B. Gulerakin and colleagues, Harran University.

The researchers concluded, "Physico-chemical results correlated with the sensory results in that panellists scored the EPS+ yoghurts as having an overall better mouthfeel but a worse flavor than EPS yogurt."

Gulerakin and colleagues published their study in International Journal of Dairy Technology ("Influence of Different Exopolysaccharide-producing Strains on the Physicochemical, Sensory and Syneresis Characteristics of Reduced-fat Stirred Yogurt." International Journal of Dairy Technology, 2009;62(3):422-430).

For more information, contact M.B. Gulerakin, Harran University, Dept. of Food Engineering, Sanliurfa, Turkey.

From the August 17, 2009, Prepared Foods E-dition