Tolkienists.org

As they are driven on by the orcs, there are occasional pauses for breath and, at one point, Pippin is handed a meal.… The grey bread, in fact, may not necessarily have been grey from age — rye flour when baked into loaves can have a natural grey look. As for the dried meat, I always think of something like South African biltong.… As much as they often seem more like hordes of goblins … than drilled troops, the Orcs, however, at least Saruman’s Uruk-hai, are actually war-bands of soldiers with some discipline (as Ugluk says, when some of Sauron’s Orcs complain about his plans: ​“By the White Hand! What’s the use of sending out mountain-maggots on a trip, only half trained.” LRC §3.03.052) We can imagine then that what is tossed to Pippin is actually a typical Orc military ration, containing the sorts of things which possess some nourishment, are portable, and which can keep for a long time.

Since the days of the Romans, a major issue for standing armies has been how to feed soldiers on campaign. The Romans issued their soldiers with some basics, including grains of various sorts, which the soldiers would grind into flour in portable hand-mills and bake into various basic forms of bread, sometimes being something like modern pita or even so-called ​“campfire bread” — dough wrapped around a stick. (For a good introduction to Roman military eating, see: Roman military bread making.) Such large, organized, and permanent armies wouldn’t appear again in Europe until the 17^th century.…