I am just in the last phase of a week long stock making bonanza
(chicken, beef, veal.)I generally follow J Pepin's guide from an old Pleasures of Cooking.I have used this method since 1980, but this current batch is my first in a long time.
My veal stock is right now cooking down to the near- demi-glace concentration that i use as frozen chunks.So, I have some questions!
Fat and 'Impurities':
I was very surprised that my 20 lb veal bones (ranging from 3 to 6 " L; plenty of marrow bones)only released 1 cup (clear) fat after they had roasted for 1.5 hours. I chilled it and was even more surprised when I tasted it (roasting beef and veal bones smell disgusting imo) and it was tasty.I garnered much more fat from my beef bones (not a surprise) and, after chilling, trashed it w/ the bones because i 'assumed'(uh oh, sure sign of trouble) it tasted as bad or worse than chicken fat (yuckOla, imo of course.)
Do my comments on the flavor and quantity gained of the veal fat--compute w/ your experience? Some people love marrow; I def do not, but might 'melted marrow' be a component in the cup of (clear)liquid fat i got? What have you cooked w/ veal fat-- eggs, potatoes, starches, stews?
When I reduce my stocks, I continually skim them of 'impurities' throughout the reducing step. When I taste bits of the 'scum', it tastes rather vile. Why? If I hadn't reduced the stock, i would be using it for sauces, soups, starch cooking, etc, and it would have been 'very tasty veal stock', yet the reduction's skimmed bits taste bad. Why?
Maybe my questions are in the "Why is there Air?" category, but if not, i would like to learn more. Thanks so much for your help.