Effect of processing treatments and storage conditions on stability of fruit juice based beverages enriched with dietary fibers alone and in mixture with xanthan gum

- A synergistic effect of xanthan and different hydrocolloids on pasteurized beverage's viscosity observed.
- Rheological behavior of dietary fibers alone in clarified juice changed over time.
- Xanthan addition to fibers slow down degradation reactions with a protecting effect.
- Pasteurization stabilized viscosity of beverages enriched in xanthan and β-glucan.

The present work aims to study the synergistic effect between xanthan gum (X) with a range of hydrocolloids such as barley β-glucan (Bg), guar gum (G), and konjac-mannan (K) on the viscosity of heat-treated fruit juice based beverages. The protective effect of X on the stability of Bg, G, and K in a fruit juice based beverage during processing and storage (0-16 weeks at 4 °C or 20 °C) was also evaluated. The results showed that pasteurization stabilized viscosity and turbidity of beverages enriched in Bg and BgX. However, the viscosity of pasteurized beverages enriched in K and G varied with storage time. In general, addition of X showed a complete protective effect against degradation at 4 °C for K (KX) whereas it provides no protection at all for G (GX). Viscosity and turbidity of beverages prepared with Bg and BgX increased significantly while those with G and K decreased slightly over time. Viscosity and turbidity changes are rapid when beverages are stored at 20 °C. We clearly evidenced that processing and storage treatments along with proper formulation are crucial to ensure technological stability of dietary fibers and X proved to be efficient to stabilize other fibers.