بررسي تاثير روشهاي خشك كردن و نوربر ويژگيهاي شيميايي زعفران در طول دوره نگهداري

Effect of drying methods and light on the cemical characteristics of saffron (Crocus sativus L.) during storage

In the present investigation, saffron(Crocus sativus L.) was dried using three methods namely: traditional (25°C), modified Spanish(55°C) and microwave oven(300 watt). Chemical changes of saffron were investigated by completely randomized design with factorial arrangement during 6 months storage and the means were compared by LSD test. The results were analyzed in level of 5%. The results indicated that the time of storage and drying method have significant effects(P<5%) on chemical properties such as coloring strength, aroma and bitterness value. Samples dried in microwave oven showed to have the highest coloring strength, aroma and bitterness value. Samples dried by modified Spanish method had higher coloring strength than traditional method, but in the view of aroma, traditional samples had significantly higher values.Regarding bitterness, both microwave oven and modified Spanish samples were in the same level but traditional sample was significantly lower than the two other methods. The coloring strength of saffron decreased but aroma increased during storage and the bitterness did not follow fixed pattern. It was noticed that in samples exposed to artificial light(20 watt) the coloring strength was decreased while, bitterness values were the same as the blank and aroma values increased at first but remained almost intact after 6 months.