Chemical and Petroleum Engineering Department, Sharif University, Tehran, I.R. IRAN
The substances responsible for saffron’s characteristic quality are crocins, picrocrocin, and safranal. The drying process is critical to the saffron quality as measured by levels of secondary metabolites, crocin (color and anti-tumor properties), picrocrocin (taste), and safranal (aroma). Four different dehydration methods were evaluated: Iranian traditional method (room temperature); dehydration with electrical oven at different temperatures; and dehydration with microwave at different powers. The results showed that the highest coloring strength was obtained when saffron treated at higher temperatures and lower times. Also the higher amount of safranal (aroma) and crocin (color) was obtained at high temperature. There was not significant difference between the amounts of picrocrocin at different temperatures in all drying methods. Between these methods, drying with microwave at 1000 W and drying at room temperature obtained the highest the lowest results respectively.
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