If it's lighter: - You might not have roasted your almonds for long enough. Try roasting them for an extra 2-3 minutes next time. If it's darker: - You probably roasted the almonds for too long in the oven. Almonds continue to cook, even when taken out of the oven: cook them a bit less next time. - The variety of almonds you purchased might just have darker skin. The taste will be the same.