There are lots of memes and questions that have surfaced over the years about the moment in the Two Towers when the Orc yells ‘looks like meat's back on the menu boys!’ It conjures a comical image in the mind of a civilized band of orcs sitting down to dine in a fancy restaurant, which is in complete contrast to what the audience has seen of their barbaric and inhumane nature.
It also goes against the idea that they would put up with ‘maggoty bread’ for three days, if they are used to a higher quality of dining. Although these lines are a creative addition on behalf of the film director Peter Jackson, Tolkien himself did actually give hints as to what the orcs might eat, when he was writing his famous works.
In the book of the Return of the King, when Frodo and Sam are deep in the midst of Mordor, surrounded by enemies on all sides, they come across a camp settled in vast plains of Wasteland. But much to their surprise, it is men, not orcs, that they see coming and going from the vast tents. When reading up on these men in the Encyclopedia of Arda, it is revealed that these men are actually slaves who were captured by the evil Lord Sauron and brought back to Mordor.
They spend their days tirelessly working to provide enough food to sustain his numerous armies, and are completely bent to his will. Who these slaves are exactly is not specified, but it is presumed that they are men of the East and South, of races like the Haradrim from just below the lands of Gondor. At this point in the Lord of the Rings, Sam and Frodo are running low on their supply of Lembas bread, which was given to them by the elves of Lothlorien, and has sustained them on their journey thus far. Sam states ‘well, whatever they have to eat or drink down there, we can’t get it.’
So it is clear that the orcs do in fact have some manner of food production in Mordor, rather than a kind of scavenger diet like that of the creature Gollum, though what exactly the food is, isn’t explicitly stated. However, the lands around are said to be fiery and desolate, and Boromir, the captain of Gondor, describes ‘the very air you breathe is a poisonous fume’ at the Council of Rivendell, so the likelihood that the orcs eat things that come from the earth like fruit or vegetables is highly improbable. It could be then, that the people are breeding and rearing animals for the orcs to eat. Cattle and Game would make the most sense. There is a possibility the animals may even include horses, as it is known that horses are bred in the dark lands. These are the black horses that the Ring-wraiths ride as they pursue the hobbits from The Shire to Rivendell.
However, the gruesome truth is that what the orcs are more likely to be eating is the slaves themselves. It is well known that they greatly desire the taste of man-flesh. It is very credible that the slaves who are being shipped up from the south are actually what is sustaining the vast hordes of Sauron’s army. We also know that they are not opposed to cannibalism, as they begin to eat the orc that is killed during the abduction of Merry and Pippin outside Fangorn Forest. It is also shown that not all of the orcs that are made are chosen as weapons, when in the forge of Isengard where the Crebain of Dunland report to Saruman the white, Lurtz is seen strangling a weaker orc, which is why he is chosen as the leader of the Uruk-hai. Perhaps those inventions who are too weak or maimed are sent as food for the others in Mordor.
When Sauron is defeated, and the quest to throw the ring into the fire of Mount Doom is completed, the great hordes of orcs in Mordor are either killed, captured, or scattered into the recesses of the hills and the mountains. Thus begins the Fourth Age of the world, in which Aragorn becomes the king of Gondor, with Arwen choosing to remain by his side rather than joining her mother in the Undying Lands.
A great era of peace begins, with the forming of the Reunited kingdom, which is written in the red book of Westmarch. And one of the first things that Aargorn does in his rule is to set free the trapped and enslaved creatures across Middle Earth, including those who had been feeding the orcs. They are allowed to return to their homelands and begin anew, under the protection of the realms.