Background High methoxyl pectin and carboxymethylcellulose (CMC) can be used as a stabilizer for directly acidified protein drinks (DAPDs). Use of pectin or CMC together with other polysaccharides and their impacts on product's rheological properties and tribological behavior are still largely unknown. This project investigated the impact of pectin and CMC, alone or in combination with guar gum, locust bean gum (LBG), and gellan gum when preparing DAPDs. The particle size distributions, rheological properties, tribological properties, and sensory properties were determined.

Results Pectin and CMC were dominating in the mixed system with other stabilizers. Increasing the concentration of hydrocolloids resulted in higher viscosity and better lubrication (lower friction coefficient). The sensoryviscosity,smoothness,coating, andstickinessintensified as the concentration of hydrocolloids increased. The type and amount of hydrocolloids had a strong effect on the sensorial texture perception, but the flavor perception was only slightly affected.

Conclusion Use of combined stabilizers may contribute to providing an effective viscosity enhancement without affecting the flavor in acidified milk beverages.