Title: Evaluating the Effect of Dietary Fiber Arabinogalactan on the Rheological and Textural Properties of Nonfat Set-type Yogurt

Dietary soluble fiber has generated interest amongst researchers and consumers recently as people have started seeking a healthier diet for heart benefits, to prevent obesity, and increase beneficial gut bacteria. Furthermore, yogurt texture is recognized as an important sensory quality that affects consumer perception. The main objective of this research was to evaluate the effect of the prebiotic substrate, arabinogalactan, a soluble fiber, on the rheological and texture properties of nonfat set-type yogurt. Arabinogalactan (1.2% by weight in the first trial and 0.8% in the second trial) was incorporated into milk and made into yogurt. Yogurt from nonfat dry milk was also prepared to generate a standard score to compare the fiber supplemented yogurts. Gel strengths of the yogurts were measured using vane rheometry after one day and after seven days of refrigerated storage. A significant difference (p < 0.05) in yield stress value between the control yogurt sample, 0.8% arabinogalactan supplemented yogurt, and 1.2% arabinogalactan supplemented yogurt was observed on day 1 as well as on day 7. Fortification with arabinogalactan did not affect rates of fermentation.