buttermilk, curdled into something else?

[Guest guest]

Hello, I am new to the group, have some kefir grains on the way, but

my question involves buttermilk. I started keeping my own buttermilk a

couple months ago, started from a supermarket carton and kept going

with fresh milk feedings as I used it in breads and pancakes, and an

occasional yummy drink. A few days ago my fridge door was left ajar

overnight, and the buttermilk (and the regular milk) curdled. Now every

time I try to refresh the buttermilk, rather than clabboring nicely, it

is pretty seperated from the whey and lots and lots of little curds,

which dont even mix well. This is nothing like the way it used to

behave, though it smells the same, and works in pancakes, but I wouldnt

drink it. Has this been invaded by other microbes, and I should start

over?

Thanks a bunch, Russ