The differences color in Thai curries is caused by the ingredients.
For example, Thai green curry is made with fresh green chillies whereas the red curry is made from dried red chillies.
Green Curry PasteGreen curry paste usually includes fresh green chilies, shallots, lemongrass, white pepper, coriander root, garlic, kaffir lime rind, shrimp paste and sea salt. Sweet basil leaves, round green eggplant and kaffir lime leaves add to the overall lovely green hue in the final curry dish.
Red Curry PasteRed curry paste is the most versatile of the curry pastes, being used in the widest range of dishes, including coconut milk-based Red Curry Chicken with Bamboo.
Red curry paste can be made with dried long red chilies , cilantro root, coriander, cumin, garlic, shallots, kaffir lime rind, white peppercorn, lemongrass, shrimp paste, sea salt and galangal.
It is prepared with chicken, duck, beef, pork, shrimp, stir-fries and haw mohk (Thai Curried Fish Mousse in Banana Leaf Cups).
The basic ingredients in a simple red curry paste are dried red chili peppers, whole cloves of garlic, sea salt, fresh lemon grass, fresh turmeric for color, and shrimp paste .