Many people struggle to set curd (yogurt) properly at home because temperature, starter culture, and milk handling play a big role. Here’s a step-by-step South Indian method that usually gives consistent results:
1. Choosing and Preparing the Milk
- Type of milk: Use full-fat cow’s milk (A2 Desi cow milk is best if available). Avoid UHT/long-life tetra-pack milk—it doesn’t set well.
- Boil the milk: Bring it to a boil, then simmer for 3–5 minutes to kill any unwanted bacteria and improve thickness.
- Cool down: Allow the milk to cool until it’s lukewarm (around 40–45 °C). A practical test: dip a clean finger—if it feels pleasantly warm but not hot, it’s ready.
2. Starter Culture (Curd/Yogurt from Previous Batch)
- Use 1–2 teaspoons of well-set, fresh curd as starter for 500 ml of milk.
- If the curd is very sour, use a smaller amount (½ tsp) to avoid excess sourness in the new batch.
- If you’re starting fresh, borrow a spoon of curd from a neighbor/friend—this is how most South Indian households maintain their culture.
3. Mixing Starter into Milk
- Take a small portion of lukewarm milk in a bowl, add the starter, and whisk well to break lumps.
- Pour this mixture back into the rest of the milk and stir gently.
- Transfer immediately to a clean steel vessel, earthen pot, or glass bowl. (Earthen pots are traditional and help set thicker, creamier curd due to slight moisture evaporation.)
4. Setting Environment
South Indian homes usually rely on warm ambient conditions:
- Cover the vessel with a lid (not airtight).
- Wrap in a thin cotton cloth or keep inside a switched-off oven, microwave, or insulated casserole if the weather is cold.
- In cooler climates, keep it near a warm place (like inside a cupboard or close to the stove after cooking).
5. Time to Set
- In warm South Indian weather: curd sets in 6–8 hours.
- In cooler weather: may take 10–12 hours.
Don’t disturb the vessel while it is setting.
6. After Setting
- Once the curd is firm and has a clean cut when you spoon it, move it to the refrigerator to stop further souring.
- Use a portion from this batch as the starter for your next curd.
Extra South Indian Tips
- For thicker curd: Add 1–2 tsp milk powder while boiling milk, or reduce milk slightly before cooling.
- For sweeter curd (not sour): Set at night and refrigerate as soon as it is firm in the morning. Longer setting = tangier taste.
- Earthenware pots: They naturally give a “hotel-style” firm curd with a mild earthy aroma.
- Don’t use chlorinated water or soap traces in vessels—they can spoil the culture.
