I think you're underestimating what could be done with preservation technology such as salting, curing, drying, pickling, fermenting etc. Meats were in fact frequently traded. Salted pork was a staple food. Cheese even more so.
And what of liquids? You're surely aware of ancient wrecks filled with amphoras? What was in them? Surely not cereals. Oils, wines, vinegars, acidic sauces such as the famed "garum" - all travel well.
I think you're underestimating what could be done with preservation technology such as salting, curing, drying, pickling, fermenting etc. Meats were in fact frequently traded. Salted pork was a staple food. Cheese even more so.
And what of liquids? You're surely aware of ancient wrecks filled with amphoras? What was in them? Surely not cereals. Oils, wines, vinegars, acidic sauces such as the famed "garum" - all travel well.