Blood Berry (3.5e Equipment)
From D&D Wiki
Round and fleshy pink in appearance, it is a mysterious fruit that grows on trees found in the most gruesome of places, the fruit masterfully mimics the taste of actual flesh and blood for the nutrients that its tree lives off is literally corpses. Favored by carnivorous creatures races as easy rations especially on a battlefield, blood berry trees can be found in old battlefields, cemeteries, and about any necromancer's laboratory. Extracting the juice and mixing it with pure alcohol makes a blood red wine called Earthblood (delicacy among those who drink actual blood.)
Nauseous Reaction (aka Blood Berry Poisoning): The first time an omnivorous creature unused to tasting raw flesh and blood tastes a blood berry they must make a Fortitude Save of 18 or more or become nauseous for 1d4 minutes. If that creature fails the save by 5 or more points, it uncontrollably vomits and becomes ill for 1d4 hours instead.
For this reason, assassins favor properly cooking the blood berry to resemble actual meat(making the taste far worse) and serving it to its victim(s). The victim(s) would no doubt be taken by surprise and unable to defend themselves as the assassin kills them.
For flesh-eating PCs: If one or more of the PCs started as or have become flesh or blood eating creatures, such as vampires or feral Drow, blood berries provide a genuine substitute to flesh. If you are using the undead hunger rules from Libris Mortis, blood berries are equal to blood, constitution gained by blood draining, or flesh in terms of sustenance. This allows PCs that would otherwise be forced to be evil by their hunger to be neutral or even good... assuming that they have an adequate supply of blood berries.