Basil Vs Thai Basil: What's The Difference?

What is sweet basil?

Sweet basil (Ocimum basilicum, sometimes called Italian basil or Genovese basil) is the most common basil variety in Western cooking. The plant has broad, rounded green leaves that are tender and slightly fuzzy, growing on green stems. The flavor is sweet and aromatic with notes of clove, anise, mint, and pepper. Sweet basil is essential in Mediterranean cuisine: pesto (the famous Genoese sauce), caprese salads, Italian pasta dishes, pizza, and tomato-based recipes. It pairs particularly well with tomatoes, garlic, olive oil, and cheese. Sweet basil is a tender annual herb that doesn't survive frost; it should be added at the end of cooking because heat destroys the volatile compounds responsible for flavor. Fresh sweet basil bunches are available in most American grocery stores year-round, with peak quality in summer months.

What is Thai basil?

Thai basil (Ocimum basilicum var. thyrsiflora, sometimes called horapha) is a basil variety used in Southeast Asian cuisine. The plant looks distinctly different from sweet basil: narrower, more pointed leaves; pronounced purple-tinged stems and flower buds; firmer, less tender texture. The flavor is also distinct: more pronounced licorice-anise notes; spicier and more peppery; less sweet. Thai basil is essential in Thai, Vietnamese, Laotian, and Cambodian cooking. It's used in Thai green curry, pad krapow, Vietnamese pho (often served on the side for diners to add), and stir-fried noodle dishes. Thai basil holds up to heat better than sweet basil; it can be added during cooking rather than only at the end. Two related varieties: holy basil (a different species, even spicier, used in Thai pad krapow) and lemon basil (with citrus notes).

How do sweet basil and Thai basil compare?

Appearance differs noticeably: sweet basil has broad rounded leaves on green stems; Thai basil has narrow pointed leaves with purple stems. Flavor differs: sweet basil is sweet and clove-like with mild anise; Thai basil has stronger licorice-anise with peppery, spicy notes. Texture differs: sweet basil is tender and delicate; Thai basil is slightly firmer and waxier. Heat tolerance differs: sweet basil wilts and loses flavor when heated; Thai basil holds up better and can be cooked into dishes. Cuisine applications differ: sweet basil is essential in Italian and Mediterranean food; Thai basil is essential in Southeast Asian food. Availability differs: sweet basil is available in most American grocery stores; Thai basil is found in Asian grocery stores and some mainstream supermarkets. Price is similar at $2-4 per bunch when available.

Can you substitute one for the other?

Not perfectly, due to dramatically different flavors. To substitute sweet basil for Thai basil (in Thai green curry, for example): the dish will lose the characteristic anise-licorice character; the result will be milder and less authentic. Adding a small amount of star anise or fennel seed during cooking can partially compensate. To substitute Thai basil for sweet basil (in pesto, for example): the result will have stronger anise notes that don't suit Italian cuisine; the pesto will taste off rather than just slightly different. For Italian dishes, sweet basil is essential. For Thai and Vietnamese dishes, Thai basil is essential.