Walmart's Great Value Ice Cream Sandwiches DON'T MELT.

[DhhD]

2. Could it be something like plaque filled arteries?

Could it be compounds like these:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1767204/

Conclusions: Chronic thromboembolic pulmonary hypertension is associated with atherosclerotic plaques with glycophorin-rich pultaceous cores, and plexogenic pulmonary hypertension with fibrous plaques. Thromboembolic material thus plays a critical role in the formation of pultaceous cores, of which erythrocyte membrane derived glycophorin is a major component.

Having cooked the heart of a lawful deer kill, plaque can even be oven cooked without completely degrading.