Properly roasted coriander seeds will have a fragrant, warm aroma, a slightly darker color, and a nutty flavor when tasted. They should also be easily crushable between your fingers.
Roasting coriander seeds enhances their flavor and aroma, making them a more potent spice. Here's how to identify properly roasted coriander seeds:
Aroma: The most obvious sign is the aroma. Raw coriander seeds have a mild, almost citrusy scent. When roasted correctly, they release a warm, fragrant, and slightly nutty aroma. If you don't smell much, they likely need more roasting.
Color: The color will deepen slightly. Raw coriander seeds are typically a light brown or beige color. As they roast, they will turn a shade or two darker. Be careful not to roast them too dark, as they can burn.
Texture: Properly roasted coriander seeds become slightly more brittle. You should be able to crush them easily between your fingers. If they are still hard and resistant to crushing, they need more roasting.
Taste: Taste a seed or two (after they've cooled slightly!). They should have a warm, nutty, and slightly citrusy flavor. If they taste bitter or burnt, you've roasted them for too long.
Visual Inspection: Keep a close eye on the seeds while roasting. They should be moving around in the pan and not sitting still, which can cause them to burn in one spot. Look for an even color change.
Roast coriander seeds in a dry pan over medium-low heat, stirring frequently. This prevents burning and ensures even roasting. Remove them from the pan as soon as they are done to prevent carryover cooking from the hot pan.