Effect of Ocimum basilicum mucilage on rheological properties and stability of doogh (Yoghurt Drink)

Doogh is an Iranian type of traditional fermented dairy based drink which is usually manufactured by mixing water, salt and yoghurt. Serum separation in Doogh is a major problem which occurs due to low pH of emulsion (≤4.00) and casein aggregation. Therefore, in present study the effect of Ocimum basilicum seeds mucilage on rheological properties and stabilization of doogh was investigated during 15 days of storage at 4 0c. Mucilage at different concentrations (0.01, 0.025 and 0.05) was added to the formulations and sample without mucilage was used as control. The samples were evaluated for rheological properties such as viscosity and flow behavior. Results showed that, with incresing of mucilage concentration viscosity increased. In terms of rheological properties, all of samples exhibited shear thining behavior, and power law model showed to be the best model for prediction of flow behavior of samples containing mucilage. Maximum and minimum values of stability were observed in the samples with 0.05% mucilge (85%) and control, respectively. This study showed that Ocimum basilicum seeds mucilage has high potantial to use as an improver of stability in doogh.