If adding buttermilk in milk turns it into curd after sometime, then how is it possible that first set of curd is made without any buttermilk?

Curd (Indian dahi) is made by the aging of milk by a quite certain microorganism or a gathering of them (lactobacillus). Including spread milk adds the microorganisms to the milk to transform it into curd. On the off chance that you don't have margarine milk, you need to scan for substitute wellsprings of the microbes. One of the spots they are found in is stew. Adding stew to a limited quantity of milk delivers a starter culture. Adding this culture to drain makes curd, which would then be able to be utilized to seed further curd bunches. On the off chance that any of those end up terrible ,, at that point you have presumably misunderstood a lot of organisms aging that bunch. You take out this clump and begin another culture.

You can rehash this procedure with any wellspring of the microscopic organisms.