The effects of three different drying methods on solubility and color parameters of fenugreek protein isolate were studied. Fenugreek protein isolate was extracted by dissolving in 0.33M NaCl solution, and then adding 1M NaOH solution to reach the pH9.25 along with isoelectric precipitation. The final isolate was subjected to freeze, vacuum oven and oven drying processes. The amount of protein in fenugreek protein isolate was 89%. Except for pH4.5 which is the isoelectric point, in other pHs there were significant differences (p<0.05) in solubility of the protein isolates with different drying methods. At all pHs the solubility of freeze dried protein isolate (FFPI) was higher than two other isolates, more over the solubility of vacuum oven dried fenugreek protein isolate (VOFPI) was higher than oven dried one (OFPI). The results of CIE lab measurements showed the most lightness for freeze drying method. These observations indicate among these three drying methods, freeze drying is more useful, because of less denaturation and damages conducted to proteins, and colorants.

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