As a consumer who is not equipped with different lab instruments, you should consider the following characteristics to buy good quality saffron:

1. Saffron stigmas are all red (no other color)
2. Saffron stigmas must be dry and brittle to the touch.
3. Saffron aroma is strong and fresh, never musty

International Organization for Standardization (ISO) has developed scientific criteria to evaluate the quality of saffron.To be more specific, good quality saffron:

• Must have humidity less than 10 percent
• Stigmas must be flexible and resistant
• Color and taste must be notorious and coloring strength must be more than 200 in 420 units of nanometer.

Classification according to quality:

• Grade A: Short stigmas
• Grade B: Stigmas attached to part of style
• Grade C: Stigmas attached to style
• Grade D: Long stigmas atta