Somaris E Quintana
University of Cartagena, Colombia
Title: Rheological characterization of tropical fruits smoothies
Biography
Biography: Somaris E Quintana
Abstract
Statement of the Problem: Food systems present different behavior depending on process condition; the rheological behavior of smoothies will be influenced by chemical composition, size, shape and arrangement of these particles comprising the dispersed phase, which influence the texture and flavor. The purpose of this study is to evaluate the rheological behavior of smoothies with tropical fruit, squash (Cucurbita moschata) and dietary fiber of pineapple (Ananas comosus).
Methodology & Theoretical Orientation: Smoothies were standardized considering the percentages of squash pulp (P), xanthan gum (XG), lactose-free skim milk (M), using design surface center response of one blocks in central points and one center points on each block. pH and the percentage of dietary fiber of pineapple (Ananas comosus) was kept constant. The rheological characterization was carried out in controlled-stress (ARES, Rheometric Scientific, UK) rheometer, using coaxial cylinder geometry. Viscous flow test was determined at 25ºC in a shear rate range of 10 s-2-10 s-1, were taken 3 minutes at each shear rate order to obtaining the steady state regime.
Findings: The samples with amount of xanthan gum around 0.2% (M4, M5, M6, M7 and M8) were stabilized until 8 days. The smoothies presented a shear thinning behavior fitted to the Ostwald de Waele model, where apparent viscosity decreased over the shear-rate range.
Conclusion & Significance: The viscous flow behavior of the smoothies investigated is strongly influenced by the amount and concentration of xanthan gum and the nature of the phases.