Male and female mussels can look surprisingly different once opened. Female mussels often have a deep orange flesh, which tends to appear richer and more vibrant. Male mussels, on the other hand, usually have a paler or creamy white color. The difference in color is mainly due to reproductive biology and the presence of eggs in females. Many people say the darker orange females have a slightly stronger, sweeter flavor, though both are equally delicious and nutritious.