2,340. Prohibited Because of Blood vs. Prohibited Because of Fat

Maachalos Assuros 7:9

The fats on the heart and on all the small intestines are permitted. These are like shumen – permitted fats – except for the top of the intestine that’s near the abomasum, which is where the small intestines start; this fat must be scraped off because it’s the forbidden fat of the small intestines. Some Geonim say that the intestine from whose top fat must be scraped is the large intestine, i.e., the colon from which waste is expelled at the end of the digestive tract.

Maachalos Assuros 7:10

There are strands and membranes in an animal’s body that are prohibited, some because of the prohibition against eating certain fats and others because of the prohibition against eating blood. When a strand or membrane is prohibited because of “Do not eat any blood” (Leviticus 3:17), one must remove it and then salt the meat as has already been discussed. If one cut it, it need not be removed. Similarly, if one roasts the meat, such strands need not be removed. When a strand or membrane is prohibited because “Do not eat any (forbidden) fat” (ibid.), it must be removed regardless of whether one plans to cut or roast the meat.