As far as I'm aware ayran is watered down kisli mylako with a touch of salt.
Very refreshing on a hot day but its no way buttermilk.
As messers Leedarkwood said they leave it to "cure" into a nasty brew, which I will not and wont ever eat or drink. Same for the butter. If you want to preserve milk, why not go the whole hog and do it properly.
I was brought up on butter milk, yoghurt, soft cheese, rosehip jelly and Mums brown brick bread for breakfast. I am sure my mother thought that if the pigs cant eat anymore of it the kids will!
Mind you it was all goats milk and in a more favorable climate for dairy products.
Maybe its just too hot here.
Here's to buttermilk