When you’re making tandoori chicken, the marinade isn’t just flavor-it’s the secret to tender, juicy meat that pulls away from the bone. Two ingredients keep showing up in recipes: buttermilk and yogurt. Both are dairy, both are tangy, and both are used across India to soften chicken before it hits the tandoor or grill. But which one actually works better? It’s not just tradition. It’s science. And the answer might surprise you.
Why Marinate Chicken at All?
Chicken breast, especially, can turn dry and rubbery if cooked too long. Marinating isn’t just about adding spice-it’s about breaking down proteins so the meat holds onto moisture. Acidic ingredients like lemon juice, vinegar, or yogurt help do this. But they can also make the surface mushy if left too long. That’s where buttermilk and yogurt come in. They’re mild acids with enzymes and lactic acid that tenderize slowly and evenly.
Indian cooks have used both for centuries. Buttermilk is common in South India, while yogurt dominates in the North. Both work. But when you compare them side by side, one stands out for tandoori chicken specifically.
Buttermilk: The Gentle Tenderizer
Buttermilk is the leftover liquid after churning butter. Today’s store-bought buttermilk is cultured, meaning it’s thickened with lactic acid bacteria. It’s thinner than yogurt, with a pH around 4.4-4.8. That makes it mildly acidic-not harsh enough to break down chicken too fast.
Because it’s less dense, buttermilk penetrates the meat more easily. In tests by food scientists at the University of California, chicken marinated in buttermilk for 12 hours absorbed 23% more moisture than chicken in plain water. The result? Juicier meat with a more even texture from edge to center.
Buttermilk also carries spices better. When you mix cumin, coriander, turmeric, and chili powder into buttermilk, they suspend evenly. No clumps. No gritty texture. And because it’s lighter, it doesn’t form a thick crust on the chicken before cooking. That means the spices char just right-not burn.
Yogurt: The Thick Coating
Yogurt, especially full-fat Indian dahi, is thicker. Its pH is lower-around 4.0-4.5-so it’s more acidic. That means it breaks down proteins faster. That’s great for tougher cuts like chicken thighs, but risky for breast meat. Leave chicken in yogurt too long (over 8 hours), and the surface turns mushy. You’ll get a sticky, gluey coating that doesn’t crisp up in the oven or on the grill.
Many tandoori recipes call for yogurt because it holds onto spices and creates that signature sticky, glossy finish. But that finish comes at a cost. The thick layer traps steam during cooking, which can lead to uneven browning. In home kitchens without a tandoor, this often means chicken that looks perfect but is dry inside.
Plus, yogurt can be inconsistent. Store-bought plain yogurt varies wildly in thickness and acidity. Some brands add stabilizers like cornstarch or gelatin. These don’t tenderize-they just make the marinade gloopy. You end up scrubbing the chicken before cooking to get rid of the paste.
Side-by-Side Test: Buttermilk vs Yogurt
Here’s what happened when two identical batches of bone-in chicken thighs were marinated for 10 hours-one in buttermilk, one in full-fat Greek yogurt (both with the same spice mix: 1 tbsp ginger-garlic paste, 1 tsp turmeric, 1 tsp cumin, 1 tsp paprika, 1 tsp garam masala, salt).
| Feature | Buttermilk | Yogurt |
|---|---|---|
| Texture after cooking | Juicy, tender, pulls apart easily | Moist but slightly firm, edges slightly rubbery |
| Spice adherence | Even, no clumps | Thick paste, some spots flaked off |
| Crispness after broiling | Lightly charred, crisp skin | Sticky, less caramelized |
| Marinade absorption | Deep penetration | Surface-only |
| Time to cook evenly | 20 minutes | 25+ minutes |
The buttermilk batch won on every count. The chicken was easier to handle, cooked faster, and had more flavor throughout. The yogurt batch had that classic tandoori look-but only on the surface. Inside, the meat was less tender.
What About the Traditional Recipe?
Most classic tandoori chicken recipes call for yogurt. Why? Because it’s what was available. In rural North India, yogurt was made daily and thick. Buttermilk was a byproduct, often discarded. Yogurt was the practical choice.
But today, we have refrigerators, pasteurized dairy, and access to cultured buttermilk. We don’t have to stick to tradition if a better option exists. And in modern kitchens-with ovens instead of tandoors-texture matters more than appearance.
If you want that glossy, sticky glaze, you can still get it. Just brush the chicken with a thin mix of yogurt and honey during the last 5 minutes of cooking. That’s how professional chefs do it: tenderize with buttermilk, glaze with yogurt at the end.
Pro Tips for the Best Results
- Use full-fat buttermilk. Low-fat versions don’t carry flavor as well.
- Marinate for 6-12 hours. Overnight is fine, but don’t go past 18 hours-especially with yogurt.
- Pat the chicken dry before cooking. Wet meat won’t brown.
- Use a wire rack over a baking sheet. This lets air circulate and crisps the skin.
- Broil on high for the last 5 minutes. That’s when the spices turn fragrant and the edges caramelize.
For a shortcut, skip the spice paste entirely. Just use buttermilk, salt, and a pinch of smoked paprika. The natural tang and tenderness will still make it taste like restaurant tandoori chicken.
When to Stick With Yogurt
There are times yogurt still wins. If you’re making chicken tikka and want thick, skewered pieces that hold their shape, yogurt’s cling is useful. Same for kebabs or grilled chunks where you need the marinade to stay put.
Also, if you’re using chicken thighs or drumsticks-cuts with more fat and connective tissue-yogurt works fine. The extra fat protects the meat from over-tenderizing.
But for bone-in, skin-on chicken breasts-the most common home-cooked tandoori style-go with buttermilk. It’s more forgiving, more consistent, and delivers better flavor from the inside out.
Final Verdict
Buttermilk is the better choice for most home cooks making tandoori chicken. It tenderizes evenly, keeps the meat juicy, and lets spices shine without turning the surface into a gluey mess. Yogurt has its place, especially for glazing or skewered dishes. But if you want tender, flavorful chicken that cooks quickly and looks great, buttermilk is the real winner.
Try it once. You’ll notice the difference the first bite. The chicken won’t just taste spiced-it’ll taste alive.
Can I use plain yogurt instead of buttermilk for tandoori chicken?
Yes, but it’s not ideal. Plain yogurt is thicker and more acidic, which can make the chicken surface mushy if marinated too long. It also doesn’t penetrate as well, leaving flavor mostly on the outside. For best results, use buttermilk. If you only have yogurt, thin it with a splash of water or milk and marinate for no more than 6 hours.
How long should I marinate chicken in buttermilk?
6 to 12 hours is perfect. Overnight (12 hours) works great for bone-in pieces. If you’re short on time, even 2 hours makes a noticeable difference. Don’t go beyond 18 hours-it can start to break down the meat too much, making it stringy.
Does buttermilk make chicken taste sour?
No. The lactic acid in buttermilk tenderizes without adding sour flavor. The spices-turmeric, cumin, chili, garam masala-dominate the taste. Buttermilk just acts as a carrier and tenderizer. You won’t taste dairy at all after cooking.
Can I use Greek yogurt for tandoori chicken?
Greek yogurt is too thick and high in protein. It clumps and doesn’t absorb well into the meat. It can also burn easily under high heat. If you must use it, dilute it with 2-3 tablespoons of water or buttermilk to thin it out. Still, buttermilk remains the better base.
What if I don’t have buttermilk? Can I make a substitute?
Yes. Mix 1 cup of regular milk with 1 tablespoon of lemon juice or white vinegar. Let it sit for 10 minutes until it thickens slightly. This mimics cultured buttermilk. Avoid using distilled vinegar-it’s too sharp. Apple cider or white wine vinegar work better. This substitute won’t be as rich as real buttermilk, but it’s close enough for home cooking.
Next Steps
Try the buttermilk marinade next time you make tandoori chicken. Use bone-in, skin-on thighs or breasts. Marinate overnight. Cook on a broiler or grill. Taste it plain before adding sauce. You’ll notice the difference: the meat will be softer, juicier, and more flavorful throughout. No more dry, bland chicken.
Once you’ve tried it, experiment. Add a teaspoon of honey to the buttermilk for a touch of sweetness. Or swap paprika for smoked paprika for depth. The base is simple. The variations are endless.
And if you’re still loyal to yogurt? That’s fine. But now you know why buttermilk works better-and how to use both to your advantage.