I believe the "stuff strained out" of schmalz is called gribeness i think your right-- it was a food i knew of, but never had... (it was too much of "family treat")
my Jewish friend where appalled at my eating habits– so much trayf!
in our house, the best dinners were roast of beef, and "please can I have some of the
blood" the juices that drained from the rare cooked meat were the best treat!
needless to say such an request would not have played well in the jewish deli– the only delis that sometimes had a fresh hot, roast of beed to slice for a sandwich. one had to go to the German deli for rare roast beef as a "cold cut" but the didn't deli's didn't serve the blood, cold meat didn't offer any.(still rare meat is juicier than well done meat) The Italian deli's cooked the beef well done too, and spiced it.-- not how i wanted it!
Jewish friends could understand that I had no injunction against pork– but
blood! 
I was at a bar (a good Irish bar) for a party, and as the waiter sliced the roast, I looked about and asked "do you have a spoon, can you server me some of the blood?" The waiter looked up, saw my blue eyes, rosy cheeks and pug nose, and said "ah an irish lass!" ( he also kindly found a spoon.. it wasn't that long ago, and "Lass" is a real stretch!)
I learned a good deal of culture and geography from local store keepers. Luckily, my neighborhood had a wonderful ethnic mix– bakeries as well as deli's came in ethnic varieties, only more– Greek and French as well as Italian and Jewish.
the french made the best butter pastries, the italian's had wonderful things with nuts and cremes made with cheese, but you went to the jewish bakery for bread.. Prejudice in our house was directed to styles of cooking–"buy some bread– but don't go to the italian bakery– their bread is no good!"
all the shops decorated the wall of their shops with maps, and pictures of their homelands. Or had special treats for saints days I had never heard of or holidays I didn't know of– Purim is still "hamintashes" to me–
It was a wonderful education– not only is all my taste in my mouth– but half my education came that way!
OP
