Mrs FP, you are just a smarty pants, aren't you?
I know I am glad I had read about sour crop before it happened so I had some idea of what was happening.
wcheek- I just hold them around their backs and squeeze gently from the feet end of the crop toward the mouth, they will open their mouths and let it come out. I do this for a couple seconds then let off, sort like if one were wretching when vomitting. You can't just squeeze and keep squeezing and not let up. The take it well. But if you can do it by the feet, I suppose that would be fine (AL), but I think that mine feel a bit more secure with my holding them the way I do. I am not a huggy kissy type with my birds, so it isn't about that.
And when squeezing, I mean it is more of a firm massage unless that doesn't result in anything. It is more important to have water for your bird than food, and unless she is on death's door, I would try the apple cider vinegar water only for a couple of days and follow what I said I will be doing with my birds. They will have an appetite, and you should see yours perk up a bit more. What is worse, if she dies without you doing something, or if she dies after you know you were trying to help her? If she is eating feed, you are also feeding the yeast in her crop. In fact, the feed has yeast in it, and most of the rest is perfect food for a sour crop to thrive, so your first action is to try to reduce this by 1.) expelling the excess gunk, then 2.) doing something to reduce the yeast in the crop which is what the ACV is supposed to do. I start out with about a tablespoon in one cup and then dilute it a bit more from there. I hope this helps.
Good luck, those of you who have birds with this problem.