The effect of fermentation on viscosity and protein solubility of Boza, a traditional cereal-based fermented Turkish beverage

Boza was prepared with corn, rice and wheat flour. Alterations in pH, water -soluble protein content and viscosity were observed during a 30 h fermenta tion period. Fermentation caused a reduction in pH, whereas the water-solub le protein content of boza significantly increased (P<0.05). The power law model described the pseudoplastic behaviour of boza. The consistency (k) an d flow behaviour index (n) values indicated that the viscosity of boza decr eases as the temperature increases. The k values of fermented and unferment ed boza samples were significantly (P<0.05) different from each other at 10 , 20 and 30 degreesC. The n values of unfermented boza did not vary signifi cantly with temperature whereas n values of fermented boza changed signific antly.