Spice, Salt, and Civilizations?

Some years ago a writer I much admire named Jared Diamond wrote Guns, Germs, and Steel, the main premise of which (though it isn't in the title, oddly) is that Eurasian civilizations took off sooner and faster than African or American due to the large number of domesticatable plants and animals living there (e.g., cattle, swine, chickens, wheat and other grains, etc.), which is why Eurasia came to dominate the rest of the world so badly once we developed ocean going vessels.

If we define civilization as the transition from nomadic to settled cultures, there may be another factor, this one concerning food.  The reason uncivilized cultures are nomadic is that food is a constant requirement but, with obvious exceptions like tropical areas, is not plentiful anywhere all year round.  Their is a time of plenty, and a time of -- well, what?  Without means to preserve (many) foods, it's either go hungry or move to new places of plenty.  Hense nomadism.

We take freezing and refrigeration (in technologically modern cultures) as the obvious way to preserve meat, fish, and other perishable food items, but that's only been quite recent (and still is no where near universal).  Prior to cold, the main preservatives used by humans were salt and spices -- even if you went to market everyday such places often had to be kept going by sellers and producers using salt & spices to keep their foods reasonably fresh for their buyers.

I don't know what the archeological evidence here is (which means I'll have to check it), but may I suggest that at least part of what triggered settled behaviors in Homo sapiens was the discovery of substances which can preserve perishable foods for fairly long periods?  At least this makes sense to me.  Nomadism is a brutal way of life, happily abandoned the moment people can do so.  On the go most of the time, carrying all you own with you, over mountain passes and deserts and other nasty places?  In truth, it doesn't even sound romantic.

When you first settle, you're still uncivilized in all other ways.  A stone-age culture that doesn't move about.  Although there are other obvious reasons, perhaps one of the causes of tropical people living "primitive" lives long after the rest of us have abandoned them, is the year-round presence of food.  They're settled because they don't have to move.  And even though many of them do use preservation methods, they're not an absolute essential; you literally can get fresh food every day.

Well.  I suppose I'm not the first person to think of this.  But I haven't seen a book entitled Spice, Salt, and Civilizations, anywhere, by anyone.  So proably not too much has been done with this idea amongst the lay public, and maybe not even among scientists.  If so, I'd love to hear about it.