I worked for Convito many years ago, in addition to an ongoing general interest in oil. In no particular order, here are various bits of fact, opinion, and, quite possibly dementia, which may be useful.
Overall, Tuscan oils tend to be characterized as "spice" or "peppery" whereas Umbrian oils tend to be heavier bodied, intense, and unctuous.
Of course there are oils from everywhere else, and I don't remember any particular stereotypes pertaining to them (Sicilian, Apulian, etc.).
French and Spanish oils tend to be much lighter in body than the classic Italian oils.
I like Greek Kalamata oils for everyday.
I also like a lot of the California oils, but they tend to be no less expensive than many of the imported, even though one would imagine there is less shipping and other costs involved. One can at least hope that they may be somewhat fresher.
Storage and age really matter, and it's very hard to have on opinion about a producer without having any idea how the product has been treated before you buy it. Heat and light being the great enemies, as with wine and even beer. When I see the great olive oil shelf displays in "gourmet" stores, sitting right in the window with the sun streaming through, I want to throttle someone.
As has been mentioned in other threads, Costco sells 2 tiers of very nice everyday oil. One, the lesser, in a very large (2 ltr?) plastic jug. The other .750?, in the typical square glass bottle. They great thing about this one is that it is actually dated by harvest on the label. So, you know that you're getting oil a year or less old. I suspect many pricey bottles on gourmet store shelves are anywhere from 1-3 yrs old. Not necessarily rancid, but certainly no longer fresh and fruity.
Also, depending on your location, Treasure Island always has at least 1-2 oils open for tasting.
FWIW, there was a very dispiriting article within the last month, I believe, in The New Yorker, on olive oil fraud. That sort of throws the whole game up for grabs, as with the great French Burgundy scandals of decades past.
The first wonderful oil I ever tasted was an Umbrian oil called Mancianti. There were 2-3 different "cuvess" of it. Even 20+ yrs. ago it was around $25 per jar. This was courtesy of Erwin Dreschler all the way back in his Bentley's Wine Bar days.
L'Appetito (2 locations, one in the plaza with the Hancock bldg, the other a bit west on Huron or Ontario?) -- stocks a nice variety of oils, including a particular line that lists harvest dates and exact regions.
Another brand I've enjoyed are the Riviera oils, distinctive for wrapping their bottles in either gold or silver foil. In addition to added light protection, I believe there is some quality code in the foil color, but I don't know exactly what it is. These tend to be very flowery, fruity oils in my experience.
Antica Abbazia is also a lighter oil, reasonably priced, that I've enjoyed.
Enjoy. Report.
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