Combinations of hydrocolloids show enhanced stabilizing effects on cloudy orange juice ready-to-drink beverages

Abstract

Cloudy ready-to-drink beverages have to be stabilized by hydrocolloids in order to prevent turbidity loss and undesirable sedimentation during storage time. The present work focuses on the stabilizing effects of pectin, guar gum and locust bean gum and the combinations of two of them on ready-to-drink beverages containing 7% of orange juice. The application and the potential combined effects of the mentioned hydrocolloids in these drinks has not been reported yet. The particle size distribution, zeta potential, viscosity, turbidity and sedimentation behaviour of beverages were measured to evaluate the impact of the different concentrations and combinations of the stabilizers. Applying 2.5 g pectin and 2.5 g guar gum per kg base was identified to be most suitable for stabilizing the turbidity over five weeks of beverages with orange juice concentrate, which contained large juice particles ranging from 0.6 to 200 μm. In contrast, 2 g pectin as well as the application of both 2.5 g pectin and 2.5 g locust bean gum per kg base maintained the storage stability of beverages containing juice concentrate, which was composed of smaller juice particles (0.5–120 μm). When locust bean gum and guar gum were applied without pectin being involved, negative effects on particle size and zeta potential could be observed leading to increased cloud loss and sedimentation rates compared with the other pectin-containing samples. The results indicated that the combination of hydrocolloids showed greater effects on long-term storage stability of the ready-to-drink beverages compared to the application of individual stabilizers.