To prevent yogurt from splitting in hot dishes, temper it by gradually adding warm sauce to the yogurt before incorporating it into the main dish, and avoid boiling it.
Yogurt splits or curdles in hot dishes because the heat causes the proteins in the yogurt to coagulate and separate from the liquid (whey). To prevent this, you need to stabilize the yogurt before exposing it to high temperatures. Here's a step-by-step guide:
Tempering the Yogurt: In a separate bowl, take the yogurt you plan to use. Gradually add a spoonful or two of the hot sauce or gravy from your dish into the yogurt, whisking constantly. This slowly raises the yogurt's temperature, preventing a sudden shock when it's added to the main dish.
Repeating the Process: Continue adding the hot sauce, a little at a time, until the yogurt mixture is warm to the touch. This process is crucial for even temperature distribution.
Incorporating into the Dish: Once the yogurt is tempered, gently stir it into the main dish. Avoid adding it directly to a boiling pot.
Low and Slow: After adding the yogurt, reduce the heat to low and simmer gently. Avoid boiling the dish, as high heat will still cause the yogurt to split.
Adding a Stabilizer (Optional): You can also add a small amount of cornstarch or flour (about 1 teaspoon per cup of yogurt) to the yogurt before tempering. Mix it well to prevent lumps. This acts as a stabilizer and helps prevent curdling.
Use full-fat yogurt, as it is less likely to split than low-fat or non-fat varieties due to its higher fat content, which helps stabilize the proteins. Also, avoid using sour yogurt, as its acidity can also contribute to curdling.