How to set Yogurt/Curd Perfectly

For turn milk into curd you should take two things into consideration.

• The temperature of the milk
• Room temperature

If either of these is not right, it may not set properly. You need milk and fresh yogurt either shop-bought or borrowed from a friend or neighbor.

Step 1: Boil milk and cool it until it is tepid.

Step 2: Take ¼ tsp of yogurt drop it into the tepid milk. Stir well. There's a popular saying among the older generation regarding the quantity of curd or buttermilk required for setting.

"கடல்  அளவு பாலுக்கு கடுகு அளவு தயர் அல்லது மோர் போதும்"
Meaning- "Curd or buttermilk as little as the size of a single grain of rye would suffice to turn an ocean of milk to curd"

Step 3: Keep in a warm place. It takes between 6 to 12 hours for the yogurt to set. It is usually set overnight.

Note:

• In very cold climes, you can keep the vessel containing the yogurt to be set inside your microwave oven without switching it on. You can also use a casserole for the purpose. 
• Alternately, place the container with the set milk on a still hot tava (after making rotis or dosas). Use a larger container turned upside down to cover it. You can do this if inspite of all precautions the curd has not set. Obviously, it's not a good idea to heat the milk again ( it will curdle with a slightly bitter taste).