May 13/Food Weekly Focus -- "This study evaluated the influence of prebiotic fibers Fibregum, Equacia, Floracia and Raftilose on color characteristics, physical, chemical, syneretic and rheological properties of yogurt and the changes in these properties while the product is stored at 6 degrees C for 14 days. Fibers (3%) were added to the yogurt and were dissolved by stirring," scientists in Kaunas, Lithuania, report.

"The fibers significantly changed the yogurt color characteristics: evaluated samples with fiber were darker than the control samples. Raftilose did not have any influence on coordinate b(star); other supplements resulted in a yellowish color. Equacia and Raftilose had the most significant influence on coordinate a(star). During the storage period, the color characteristics of the yogurt did not change. All fibers improved the syneretic stability of the yogurt: Equacia had the most significant effect. According to flow curves within the evaluated shear rate range (0-500 s(-1)), the strongest structure was observed in the yogurt sample with Equacia. Other fibers had a lower influence on the measured rheological properties of yogurt compared to the control sample," wrote M. Kulikauskiene and colleagues.

The researchers concluded, "None of the fibers influenced the acidity of the fresh or stored yogurt."

Kulikauskiene and colleagues published their study in Milchwissenschaft - Milk Science International ("Influence of Prebiotic Fibers on Yogurt Properties." Milchwissenschaft - Milk Science International, 2009;64(2):187-191).

For more information, contact M. Kulikauskiene, Kaunas University Technology, Food Institute, Taikos 92, LT-51180 Kaunas, Lithuania.

From the May 26, 2009, Prepared Foods E-dition