Thai cuisine achieves its complex blend of flavors through the use of fresh, aromatic herbs. These plants provide the foundation for the characteristic balance of sweet, sour, salty, and spicy notes. Beyond the kitchen, these same herbs are woven into Thai wellness traditions, valued for their restorative properties.
The philosophy of Thai cooking centers on creating a multi-sensory experience. Herbs contribute flavor, aroma, and a range of textures that define the cuisine’s unique character, making them a part of Thailand’s cultural identity.
Foundational Culinary Herbs
Lemongrass, a tall perennial grass, offers a distinct citrusy and slightly minty fragrance. It imparts a refreshing and pungent taste without the bitterness of lemon. The lower, swollen part of the stalk is the most aromatic portion used in cooking. Lemongrass is a signature component in the hot and sour soup, Tom Yum.
Galangal, a rhizome from the ginger family known as ‘kha,’ offers a sharp, citrusy, and piney flavor that is more pungent than ginger. This aromatic root is used to create the complex broths of soups like Tom Kha Gai, a creamy chicken and coconut soup. It is also a component in many red and green curry pastes.
The glossy, double-lobed kaffir lime leaf, or makrut lime, provides a recognizable aroma in Thai cuisine. The leaves have a potent citrus and floral fragrance that infuses soups and curries, such as Panang or green curry. The leaves are also used in dishes like Thai fish cakes and certain salads.
Thai basil (Horapha) has purple stems and a sweet, anise-like flavor. Unlike Italian basil, it is more robust and can withstand high cooking temperatures, making it suitable for stir-fries and curries. It is often added at the end of cooking to preserve its fresh quality and is also served fresh with noodle soups.
Traditional Medicinal Applications
Beyond their culinary roles, many Thai herbs are used in traditional medicine. Turmeric (‘khamin chan’) is recognized for its anti-inflammatory properties. The yellow root contains active compounds called curcuminoids, which are used for treating ailments from digestive issues to joint pain. It is an ingredient in medicinal teas and is also used topically.
Pandan leaves, with their sweet and calming aroma, are used in Thai wellness. While known for flavoring desserts and rice, in a medicinal context, pandan is used to help manage pain. It is also used in herbal infusions for its soothing effect, either as a paste or an extract.
Holy basil (Kaphrao) is used in both cuisine and medicine. As an adaptogen, it is used in traditional practices to help the body manage stress and support hormonal balance. For its therapeutic effects, it is consumed as a herbal tea or in capsule form, separate from its culinary use in stir-fries.
Herbal compress massage (Luk Pra Kob) is a feature of Thai wellness. This therapy involves steaming a bundle of herbs and applying it to the body to soothe muscles and improve circulation. The compresses contain a blend of herbs like lemongrass, turmeric, and kaffir lime, combining thermal therapy with the plants’ healing properties.
Distinguishing Similar Herbs
Differentiating between galangal and ginger can be a challenge. While related, their flavors are different. Galangal has smoother, paler skin with distinct rings, and its flesh is harder and more fibrous than ginger. In terms of taste, ginger is pungent and spicy, while galangal is sharper with pine-like notes. Substituting one for the other will alter a dish’s taste.
The two main types of basil in Thai cuisine are Thai basil (Horapha) and holy basil (Kaphrao). Thai basil has narrow, smooth leaves and purple stems, with a sweet, anise-like flavor. Holy basil has fuzzy leaves with serrated edges and a peppery, clove-like flavor. Their applications are distinct: Thai basil is used in curries, while holy basil is used in spicy stir-fries like Pad Krapow.
Preparation and Sourcing
Proper preparation helps release the most flavor from Thai herbs. For lemongrass, bruise the bottom few inches of the stalk with a knife to release its oils before slicing or adding it whole to a soup. The tough upper stalk can be bruised for broths but should be removed before serving.
Galangal’s dense nature requires a sharp knife to slice it into thin rounds for infusing liquids; these woody slices are not eaten. If the galangal is to be consumed, it must be finely minced or pounded. Kaffir lime leaves are often used whole after being torn in half with the central rib removed to release their fragrance.
Fresh Thai herbs are available at Asian grocery stores, and some supermarkets may carry lemongrass and Thai basil. When fresh herbs are unavailable, frozen versions are a good alternative, as they retain much of their flavor. Dried herbs are also an option, particularly for kaffir lime leaves, though their potency is lower than fresh or frozen.