Effect of Different Drying Methods on the Physicochemical Properties and Bioactive Components of Saffron Powder.

Saffron is the most expensive spice in the world; so, determining optimum conditions for its processing is crucial. The most important processing stage of saffron is drying of its stigma, which should be optimized and there are no reports on reactance-window (RW) of saffron. In this research, drying of saffron with traditional, RW, and oven driers and at three temperatures of 60, 70 and 80 °C, as well as room temperature (25 °C) were studied. Regarding process duration, RW drier with 200 μm Mylar membrane and oven drier were the best methods with average drying time of 25.28 and 22.28 min, respectively. As far as the concentration of bioactive ingredients, i.e., picrocrocin, safranal, and crocin, of saffron was concerned, RW drier with Pyrex glass was better than other driers, resulting in 112.83 [Formula: see text] of picrocrocin, 51.79 [Formula: see text] of safranal, and 274.76 [Formula: see text] of crocin. The panelist most favored those saffron samples dried by RW with 300 μm Mylar membrane.