Subhadrika Sen
Immediate fridge storage: Once you have made the curd or purchased it, store it inside the refrigerator immediately. Keeping it outdoors in room temperature will spoil it.
Check the container: If you notice that the container where you have stored the curd is bulging out, then it is best to not consume that curd.
Colour check: If the colour of the curd is yellow with any grey, black, green spots, the curd must immediately be thrown away.
Smell signs: If you open the curd container and a very tangy or acidic smell hits your nose, then the curd has definitely gone bad.
Texture change: Usually curd may be slightly lumpy and solid jelly like with a pale yellow liquid but if you notice the texture to be overly lumpy or very slimy, it might be best to not consume it.