I ran some figures for how much food my 6000 dton cruiser needs. (along with pretty much everything else about that ship. I need a life.
)I got my figures from here:
http://www.projectrho.com/rocket/lifesupport.php#id--Consumables--How_Much_Food?
Basically, starship food in my universe (small ship, max 12000 dton, running a naval campaign) is simply stored as fresh, dry, or frozen. A large part of the dry goods are canned. For my ship's crew of 350 men, and food storage for 15 weeks (the standard for most ships I.m.t.u.), it comes out to pretty much exactly 30 dtons, packed tightly. (behold the standard Imperial navy square can!) The food is generally cooked or prepared before meals, and the ship carries 3 cooks to do it. The galley on my deckplan takes up about 12 dtons, but I assume both that and the food stores tonnage or included in the slop from stateroom tonnage.
That works out so 1 dton of food stores is 1225 man/days.
On a side note, 15 weeks of food is pretty limiting when it's 8 parsecs at J-2 to your hunting ground for enemy shipping. Since my ship has about 30 dtons of cargo space when fully outfitted, using half of that gets food stores to 22.5 weeks, or about 6 months.
I.m.t.u., some vegetables and lots of breads, potatoes and fish make up the typical spacer's diet, but that has everything to do with several factors that I doubt apply to the same degree to anyone else's universe.