I assume you aren't describing a hemoptysis. As an adult, most of my CF issues have been GI. Even still, I don't catch colds, if something nails my lungs it is serious. About a year ago I was fighting a non specific lung infection when I hocked up a marble sized blood clot. It happened at a moment when I sneezed, coughed and maybe belched at once. I figured the last place it would have come from was my lungs so I went about an ENT and GI check waiting to see my CF pulmonologist.
Although it was essentially over and done with by the time I saw the doctor who knew from whence my clots came, I had a collection of individual clots, kept separate, cold and annotated as about the only remaining evidence of pleural effusion. Having been through the usual sinus surgeries and the indignitiy of canker mouth, I know bloody sputem from other tissue types. Not to mention I keep a little of my lung in a jar so I sort of know what the alveoli tissue would be like. As a Nurse, my guess is you know exactly what you have in your hand.
The short of it for me was momentary terror when the second hemoptysis happened. There was no doubt it came from my lungs and it was punctuated by the most exquisite pain above my left kidney. The pain was shocking in the literal sense. Although momentary, less than a second, the pain caused my entire body to wretch and spasm wildy. Most hemoptysis in CF isn't from pleural effusion rather the ravages of lung infection and so forth.
Exactly what I had in hand was clearly a formed blood clot, now surrounded by a layer of mucus. It easily could have been lung tissue holding some or all of the collected stuff together. As it turns out, the origin was such that lung tissue shouldn't have been in what I brought up. Without a doubt if you can, save it. It didn't occur to me at the time but now I wish I had sectioned one of my clots. I am a semi-retired research geneticist and I often culture and identify my own infections and such. From the pink nature and the tissue like cohesive structure, it could be a chunk of lung.
I had never known that the granular crap that ends up being crunched unwittingly between my teeth to be dried mucus. That is a new one. I had always assumed that they were crysalis formed in the lungs that encapsulate resistant infections as in TB historically. This is a little out of school, but at a very young age, I was tutored through through human anatomy. My tutor called me in one early morning to get a peek at a tuburcular lung. Crysali encapsulate the pockets of TB bacteria. Most of them were small but I could see where so many little granules combined to make a golf ball sized rock laying in the collaped lung tissue.
The term "foul tasting" must be faint praise. I can't honestly say my cruchies have been remarkable but from the moment that chest was opened, I have an olfactory memory that endures to this day. This is actually a fantastic mechanism the body had developed to deal with intractable infection. Without this ability to entomb an infectious mass, TB and so many other diseases would have been quickly fatal. Next time you gag on a crysalis, thank your parents for the great genes to make a carbunkle. You don't see that term so often now but a lot of atheletes know carbunkles well. Somebody injures the soft tissue in a joint, infection gets in where the blood can't and boom you have an incurable infection. After a few months you begin to notice that a bulge is below one knee cap and not the other. Enter encapsulation of the infection.
LL