Answer by Kris Rosvold:
1) The pigs are fed what pigs are designed to eat, instead of the C.A.F.O. "food" used in the US which consists of large amounts of soy, corn, offal, and drugs… LOTS of drugs. The US Virginia Ham I grew up with in 1970 mumble had a lot of the complexity of flavor that good prosciutto has. One of the things which made these hams so wonderful is that pigs love acorns.
2) Few chemicals.
3) No excessive fat from force feeding.
So… the Italians start with a far better and tastier meat than we do.
4) The Process: US Hams used to be dry packed in sugar, salt, a little saltpeter, and some spices and, if you're really lucky, some bourbon, for a week or more (as much as five or seven weeks in some cases) before smoking at about 95 to 110 degrees for a couple of weeks or more. Then the cured ham is stored in a cool dry spot (typically 45 to 48 degrees at up to 70% R.H.) like a cellar, for up to six months before it's sold. It is a long, slow process to produce a good ham… With VERY rare exceptions this is no longer true. What was a 30 pound raw ham could loose enough water (20 to 30%) to become a 23 pound ham… giving you a major concentration of flavors.
Now, the C.A.F.O. Industrialized "Ham" process is generally to inject a water based "flavor solution" of salt, sugar, sulfites, and chemical flavorings (adding water) and "smoke" it in a +200 degree oven for a day or two, to simulate the look and flavor of a real dry aged ham. That 30 pound raw ham could easily come away weighing as much as 28 pounds. Then pack, ship, and sell as quickly as possible.
This is the key difference.
The Italian process is even longer, and more painstaking than the US process…
Here's how it's done from one of the world's acknowledged Expert houses:
(Yes, I've had one, there is nothing to compare it to, at any price!)
Here's a method to build your own… BUT, remember that the G.I.G.O. Law applies. If you attempt to start with a raw C.A.F.O. ham you won't get a good product. You need wild fed meat to get even a decent ham out.
I've always used the Virginia process and it's well worth the persnicketyness, fuss and time. With a bit of practice and loads of patience you end up with a ham that could easily cost you $20 to $25 a pound if folks only knew what they were missing.