Rheological properties of palmate-tuber salep (PTS) (2, 3, 4, and 5% w/w) and rounded-tuber salep (RTS) (4, 5, 6, and 7% w/w) were compared to carboxymethyl cellulose (CMC) (1, 1.5, 2, and 3% w/w) and guar gum (0.75, 1, 1.5, and 2% w/w) at four temperatures (5, 25, 45, and 65 °C). Samples were subjected to a programmed shear rate increasing from 0 to 300 s-1 in 3 min using a rotational viscometer. The power law model well described the rheological behavior of hydrocolloid solutions. At all concentrations and temperatures, the flow curves of all hydrocolloids showed a shear-thinning behavior. The power law model parameters (k and n values) for all hydrocolloids were dependent to changes in concentration and temperature. A power model was used to evaluate the concentration effect on apparent viscosity (50 s-1). The concentration dependency of apparent viscosity for saleps was higher than that of CMC and guar gum, respectively. This dependency increased as temperature increased. Temperature dependency of the apparent viscosity for hydrocolloid solutions was successfully described by the Arrhenius model. The highest and lowest temperature dependencies of apparent viscosity were belong to PTS and CMC, and guar gum, respectively. RTS solutions had an intermediate temperature dependency. This dependency decreased as concentration increased.

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